PC87591L-VPC - National Semiconductor

PC87591E, PC87591S and PC87591L LPC Mobile Embedded Controllers

PRELIMINARY

March 2004

Revision 1.07

PC87591E, PC87591S and PC87591L

LPC Mobile Embedded Controllers

General Description

The National Semiconductor PC87591E, PC87591S and

PC87591L are highly integrated, embedded controllers with

an embedded-RISC core and integrated advanced func-

tions. These devices are targeted for a wide range of porta-

ble applications that use the Low Pin Count (LPC) interface.

The PC87591S is targeted for security applications and in-

cludes supporting hardware such as the Hardware Random

Number Generator. The PC8591L replaces the on-chip

flash with 4K of boot ROM for value solutions using shared

BIOS architecture. “PC87591x” refers to all the devices.

The PC87591x incorporates National’s CompactRISC

CR16B core (a high-performance 16-bit RISC processor),

on-chip flash (ROM for the PC87591L) and RAM memories,

systemsupportfunctionsandaBusInterfaceUnit(BIU)that

directly interfaces with optional external memory (such as

flash) and I/O devices.

System support functions include: WATCHDOG and other

timers, interrupt control, general-purpose I/O (GPIO) with

internal keyboard matrix scanning, PS/2®Interface,

ACCESS.bus®interface, high accuracy analog-to-digital

(ADC) and digital-to-analog converters (DAC) for battery

charging, system control, system health monitoring and an-

alog controls.

The PC87591x interfaces with the host via an LPC interface

that provides the host with access to the Keyboard and em-

bedded controller interface channels, integrated functions,

Real-Time Clock (RTC), BIOS firmware and security func-

tions.

Like members of National’s SuperI/O family, the PC87591x

is PC01 and ACPI compliant.

Outstanding Features

■Host interface, based on Intel’s LPC Interface Speciﬁ-

cation Revision 1.0, September 29th, 1997

■PC01 Rev 1.0, and ACPI 2.0 compliant

■16-bit RISC core, with 2 Mbyte address space, and

running at up to 20 MHz

■Software and Hardware controlled clock throttling

■Shared BIOS ﬂash memory (internal and/or external)

■Y2K-compliant RTC

■84/117 GPIO ports (for 128-pin/176-pin packages)

with a variety of wake-up events

■Extremely low current consumption in Idle mode

■JTAG-based debugger interface

■128-pin and 176-pin options, in LQFP package

(PC87591L is 176-pin only)

Block Diagram

Core Bus

Peripheral Bus

Bus

KBC + PM

Host I/F

RTC

Processing

Unit

RAM

External

BIU

CR16B Core

32.768 KHz

ICU

HFCG

PMC

ADC

ACB

GPIO WDG

FLASH or ROM

MIWU

Memory + I/O

MFT16

Timer +

Adapter

PS/2

I/F

(X2)

CLK DAC

(X2)

Memory

Debugger

I/F

Shared mem.

+ Security

LPC

I/F Serial

IRQ SMI

Functions

Internal Bus

CR Access

DMA

JTAG

KBSCAN +

ACM USART

Peripherals

LPC Bus I/F

I/F Functions

PWM

Reset &

Config

MSWC

Bridge

Controlled

Host

National Semiconductor is a registered trademark of National Semiconductor Corporation. All other brand or product names are trademarks or registered trademarks of their respective holders.

www.national.com 2 Revision1.07

Features (Continued)

PC87591E/S/L

Device-Speciﬁc Information

The following table compares features for the devices in the PC87591x family. The features listed below are a superset of

the PC87591x family.

Features

■Processing Unit

—CompactRISC CR16B 16-bit embedded RISC pro-

cessor core (the “core”)

—2 Mbyte address space

■Internal Memory

—Up to 128 Kbytes of on-chip ﬂash memory (4 Kbytes

of ROM in the PC87591L)

—Supports BIOS (ﬂash) memory sharing with PC host

—On-chip ﬂash is ﬁeld upgradable by host, CR16B,

parallel interface or JTAG

—Boot blocks for both CR16B and Host Code

—Memory contents protection and security

—Hardware-protected boot zone with block protection

circuit

—2K (PC87591E/L) or 4K of on-chip RAM (PC87591S)

—All memory types can hold both code and data

■Expansion Memory (Optional in 176-pin package)

—Up to 1 Mbyte of additional code and data

—Supports BIOS (ﬂash) memory sharing with PC host

—Supports external memory power-down mode

—Field upgradable with ﬂash or SRAM devices

—Supports host-controlled code download and up-

date

—Bus Interface Unit (BIU)

❏Three address zones for static devices (SRAM,

ROM, ﬂash, I/O)

❏Conﬁgurable wait states and fast-read, single-

cycle bus cycles

❏8- or 16-bit wide bus

■LPC System Interface

—Synchronous cycles, up to 33 MHz bus clock

—Serial IRQ

—I/O and Memory read and write cycles

—Bootable memory support

—Bus Master read and write cycles

—Reset input

—Base Address (BADDR) strap to determine the base

address of the Index-Data register pair

—LPCPD and CLKRUN support

—FWH Transaction support

■Security Function Support

—Random Number Generator (RNG)

—Full Random using temperature, voltage and system

noise.

—Memory access protection

Embedded Controller System Features

■Host Bus Interface (HBI)

—Three host interface channels, typically used for the

KBC, ACPI Private or Shared EC channels

—8042 KBC standard Interface (legacy 6016, 6416)

—Intel 80C51SL compatible

—IRQ1 and IRQ12 support

—Fast Gate A20 and Fast Host Reset via ﬁrmware

—PM interface port (legacy 6216, 6616)

—ACPI Embedded Controller with either Shared or

Private interface

—IRQ, SMI or SCI generation

Function PC87591E

128-Pin PC87591E

176-Pin PC87591S

128-Pin PC87591S

176-Pin PC87591L

176-Pin

Flash Size 64K 64K 128K 128K –

ROMSize ––––4K

RAMSize 2K2K4K4K2K

General-Purpose Input/Output Ports (GPIO) 62 93 62 93 93

Shared BIOS NO YES NO YES YES

RNG NO NO YES YES NO

Memory Protection NO NO YES YES YES

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PC87591E/S/L

Features (Continued)

■Interrupt Control Unit (ICU)

—31 maskable vectored interrupts (of which 26 are ex-

ternal)

—General-purpose external interrupt inputs through

MIWU

—Enable and pending indication for each interrupt

—Non-maskable interrupt input

■Multi-Input Wake-Up (MIWU)

—Supports up to 32 wake-up or interrupt inputs

—Generates wake-up event to PMC (Power Manage-

ment Controller)

—Generates interrupts to ICU

—Provides user-selectable trigger conditions

■General-Purpose I/O (GPIO)

—84/117 port pins in 128-pin/176-pin package, re-

spectively.

—I/O pins individually conﬁgured as input or output

—Conﬁgurable internal pull-up resistors

—Special ports for internal keyboard matrix scanning

❏16 open-collector outputs

❏Eight Schmitt inputs with internal pull-ups

—Input for system On/Off switch

—27 external wake-up events

—Low-cost external GPIO expansion through the

BIU I/O Expansion protocol

■PS/2 Interface

—Supports four external ports: Keyboard, mouse and

two additional pointing devices

—Supports byte-level handling via hardware accelera-

tor

■Two ACCESS.bus (ACB) Interface modules. Each is:

—Intel SMBus® and Philips I2C® compatible

—ACCESS.bus master and slave

—Up to three simultaneous slave addresses detected

—Supports polling and interrupt controlled operation

—Generates a wake-up signal on detection of a Start

Condition while in Idle mode

—Optional internal pull-up on SDA and SCL pins

■Two 16-bit Multi Function Timer (MFT16) modules.

Each module:

—Contains two 16-bit timers

—Supports Pulse Width Modulation (PWM), Capture

and Counter

■Universal Synchronous/ Asynchronous Receiver-trans-

mitter (USART)

—A full-duplex USART channel

—Programmable baud rate

—Data transfer via interrupt or polling

—Synchronous mode with either internal or external

clock

—7-, 8- or 9-bit protocols.

■Pulse Width Modulation (PWM) Module

—Eight outputs

—8-bit duty cycle resolution

—Common input clock prescaler

■Timer and WATCHDOG (TWM)

—16-bit periodic interrupt timer with 30 µs resolution

and 5-bit prescaler for system tick and periodic

wake-up tasks

—8-bit WATCHDOG timer

■Analog to Digital Converter (ADC)

—Fourteen channels, with 10-bit resolution

—Sigma-delta technology for high noise rejection

—Three voltage measurements and one temperature

measurement every 100 ms

—Internal voltage reference

■Hardware Monitoring

—Controlled by embedded controller

—System Voltage Measurement

❏Up to eight external measurement points

❏Four internal measurement points

❏Smart power failure detection

—Diode-Based Temperature Measurement

❏Software-controlled fault detection

❏Hardware-monitored over-temperature detection

—Production time calibration using ﬂash parameters

■Digital to Analog Converter (DAC)

—Four channels, 8-bit resolution

—1µs conversion time for 50 pF load

—Full output range from AGND to AVCC

■Analog Comparators Monitor (ACM)

—Eight comparator inputs on KBD scan inputs

—6-bit input measurement resolution

—Scan and Threshold modes

—Supports low-current system wake-up

■Development Support Features

—Interface to debugger via JTAG pins

❏ISE/ADB mode

❏On-board Debug mode

—Flash programing via JTAG

■CR16B Access to Host Controlled Functions

—Enabled when host inactive

Host Controlled Functions Features

■Supports Microsoft®Advanced Power Management

(APM) Speciﬁcations Revision 1.2, February 1996

—Generates the System Management Interrupt (SMI)

■PC1 and ACPI Compliant

—PnP Conﬁguration Register structure

—Flexible resource allocation for all logical devices

❏Relocatable base address

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Features (Continued)

PC87591E/S/L

❏15 IRQ routing options

■Legacy free support

■Real-Time Clock (RTC)

—DS1287 and MC146818 compatible

—242-byte battery backed-up CMOS RAM

—Calendar including century and automatic leap-year

adjustment (Y2K compliant)

—Optional adjustment for daylight saving time

—BCD or binary format for timekeeping

—Three individually maskable interrupt event ﬂags:

periodic rates from 122 µs to 500 ms; time-of-day

alarm, once-per-second to once-per-day

—Double-buffer time registers

—Alarm wake-up

■Mobile System Wake-Up Control (MSWC)

—Wake-up on detection of RI1, RI2, RING activity

❏External modem ring on serial port

❏Ring pulse or pulse train on RING input signal

❏Software-controlled off events

—Optional routing of power-up request on IRQ and/or

SMI lines

Clocking, Supply and Package Information

■Strap Input Controlled Operating Modes

—Turn on shared BIOS

—TRI-STATE

—Development

—On-board development

—Programing environment

■Clocks

—Single 32.768 KHz crystal oscillator

—LPC clock, up to 33 MHz

—On-chip high frequency clock generator

❏CPU clock 4-20 MHz

❏Software-controlled frequency generation

❏Multiplier source 32 KHz input

—32 KHz clock out

—CR16B clock out

■Power Supply

—3.3V supply operation

—5V tolerance and back-drive protection on all pins

(except LPC bus pins and keyboard scan inputs)

—Separate supply for Host I/F (VDD) and Embedded

Controller functions (VCC)

—Backup battery input for RTC, and wake-up conﬁgu-

ration.

—Reduced power consumption capability

—Four power modes, switched by software or hard-

ware

❏Active mode current (TBD mA)

❏Active mode executing WAIT

❏Idle (15 µA)

❏Power off for RTC only (0.9 µA typical) from

backup battery

—Automatic wake-up on system events

■Package Options

—128-pin LQFP package

—176-pin LQFP package for more GPIO pins, Expan-

sion Memory use and development systems

Revision 1.07 5 www.national.com

PC87591E/S/L

Revision Record

Revision Date Status Comments

April 11, 00 0.13 External version of Architectural Speciﬁcation

December 25, 00 1.0 Preliminary

May 1, 01 1.02 Preliminary

May 8, 01 1.03 Preliminary

July 19, 01 1.04 Preliminary

October 28, 01 1.05 Preliminary

July 2002 1.06 Preliminary

April 2004 1.07 Preliminary: All references to CSP package are removed in Rev 1.07.

www.national.com 6 Revision1.07

PC87591E/S/L

Table of Contents

Embedded Controller System Features .................................................................2

Host Controlled Functions Features ......................................................................3

Clocking, Supply and Package Information ...........................................................4

Revision Record ....................................................................................................5

1.0 Introduction

1.1 DOCUMENT ORGANIZATION ..................................................................................................23

1.2 GENERAL DESCRIPTION ........................................................................................................23

1.2.1 System Connections ....................................................................................................23

1.2.2 Power Management ....................................................................................................23

1.2.3 Operating Environments ..............................................................................................25

1.3 INTERNAL ARCHITECTURE ....................................................................................................25

1.3.1 Processing Unit ...........................................................................................................26

1.3.2 Bus Interface Unit and Memory Controller (BIU) .........................................................26

1.3.3 On-Chip Memory .........................................................................................................26

1.3.4 Peripherals ..................................................................................................................27

1.3.5 Host-Controller Interface Modules ...............................................................................28

1.3.6 Host-Controlled SuperI/O Modules and Host Interface ...............................................29

1.4 OPERATING ENVIRONMENTS ................................................................................................29

1.4.1 IRE Environment .........................................................................................................29

1.4.2 OBD Environment ........................................................................................................30

1.4.3 DEV Environment ........................................................................................................30

1.4.4 PROG Environment .....................................................................................................30

1.5 MEMORY MAP ..........................................................................................................................30

1.5.1 Core Address Domain Memory Map ...........................................................................33

Accessing Base Memory .....................................................................................35

Accessing Expansion Memory .............................................................................36

Accessing I/O Expansion Space ..........................................................................37

1.5.2 Host Address Domain Memory Map ............................................................................38

1.5.3 Core Access to Host Controlled Peripherals ...............................................................38

2.0 Signal/Pin Description and Configuration

2.1 CONNECTION DIAGRAMS ......................................................................................................39

2.2 BUFFER TYPES AND SIGNAL/PIN DIRECTORY ....................................................................41

2.2.1 ACCESS.bus (ACB1 and ACB2) Interface ..................................................................42

2.2.2 Analog Interface ..........................................................................................................42

2.2.3 Clocks ..........................................................................................................................42

2.2.4 Core Bus Interface Unit (BIU) ......................................................................................43

2.2.5 Development System Support .....................................................................................44

2.2.6 General-Purpose I/O (GPIO) and Internal Keyboard Scan .........................................45

2.2.7 Host Interface ..............................................................................................................48

2.2.8 Interrupt and Wake-Up Inputs (ICU and MIWU) ..........................................................49

2.2.9 Power and Ground ......................................................................................................49

2.2.10 PS/2 Interface ..............................................................................................................50

2.2.11 Strap Configuration ......................................................................................................50

Table of Contents (Continued)

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PC87591E/S/L

2.2.12 Mobile System Wake-Up Control (MSWC) ..................................................................51

2.2.13 Timers and PWM .........................................................................................................51

2.2.14 Universal Synchronous/Asynchronous Receiver/Transmitter (USART) ......................51

2.2.15 Internal Pull-Up and Pull-Down Resistors ...................................................................52

2.3 STRAP PINS .............................................................................................................................53

Setting the Environment ......................................................................................53

Other Strap Pin Settings ......................................................................................53

System Load on Strap Pins .................................................................................53

Strap Pin Status Register (STRPST) ...................................................................54

2.4 ALTERNATE FUNCTIONS ........................................................................................................54

2.4.1 GPIO with Alternate Functions ....................................................................................54

2.4.2 System Configuration Registers ..................................................................................58

Module Configuration Register (MCFG) ..............................................................58

External Interrupts Configuration Register (EICFG) ............................................59

2.4.3 GPIO with Echo Configuration .....................................................................................59

Input to Output Echo Enable Register 1 and 2 (IOEE1 and IOEE2) ....................60

3.0 Power, Reset and Clocks

3.1 POWER .....................................................................................................................................62

3.1.1 Power Planes ..............................................................................................................62

3.1.2 Power States ...............................................................................................................62

3.1.3 Power Connection and Layout Guidelines ..................................................................63

3.2 RESET SOURCES AND TYPES ...............................................................................................65

3.2.1 VPP Power-Up Reset ...................................................................................................66

3.2.2 VCC Power-Up Reset ...................................................................................................66

3.2.3 WATCHDOG Reset and Debugger Interface Reset ....................................................66

3.2.4 Warm Reset .................................................................................................................66

3.2.5 Host Domain Reset .....................................................................................................67

Using RESET2 Input ............................................................................................67

Host Domain Reset Actions .................................................................................67

3.3 CLOCK DOMAINS .....................................................................................................................68

LPC Clock ............................................................................................................68

RTC (32 KHz) Clock ............................................................................................68

4.0 Embedded Controller Modules

4.1 BUS INTERFACE UNIT (BIU) ...................................................................................................69

4.1.1 Features ......................................................................................................................69

4.1.2 Functional Description .................................................................................................69

Interface ...............................................................................................................69

Static Memory and I/O Support ...........................................................................69

Byte Access .........................................................................................................69

Clock and Bus Cycles ..........................................................................................70

4.1.3 Clock Cycles ................................................................................................................71

Optional Clock Cycles ..........................................................................................71

Other Clock Cycles ..............................................................................................71

Table of Contents (Continued)

www.national.com 8 Revision1.07

PC87591E/S/L

Control Signals ....................................................................................................72

4.1.4 Early Write Bus Cycle ..................................................................................................72

4.1.5 Late Write Bus Cycle ...................................................................................................74

4.1.6 Normal Read Bus Cycle ..............................................................................................76

4.1.7 Fast Read Bus Cycle ...................................................................................................79

4.1.8 I/O Expansion Bus Cycles ...........................................................................................80

4.1.9 Development Support ..................................................................................................81

Bus Status Signals ...............................................................................................81

Core Bus Monitoring ............................................................................................82

4.1.10 BIU Registers ..............................................................................................................83

BIU Configuration Register (BCFG) .....................................................................83

I/O Zone Configuration Register (IOCFG) ...........................................................84

Static Zone Configuration Register (SZCFGn) ....................................................85

4.1.11 Usage Hints .................................................................................................................86

4.2 DMA CONTROLLER (DMAC) ...................................................................................................87

4.2.1 Features ......................................................................................................................87

4.2.2 Functional Description .................................................................................................87

4.2.3 Channel Assignment in PC87591x ..............................................................................87

4.2.4 Transfer Types ............................................................................................................88

Direct (Fly-By) Transfers ......................................................................................88

Indirect (Memory-to-Memory) Transfers ..............................................................89

4.2.5 Bus Policy ....................................................................................................................90

Intermittent Operation Mode ................................................................................90

Continuous Operation Mode ................................................................................90

4.2.6 Operation Modes .........................................................................................................91

Single Transfer Operation ....................................................................................91

Double Buffer Operation ......................................................................................91

Auto-Initialize Operation ......................................................................................92

4.2.7 Software DMA Request ...............................................................................................92

4.2.8 DMAC Registers ..........................................................................................................92

DMAC Register Map ............................................................................................92

Device A Address Counter Register (ADCAn) .....................................................93

Device A Address Register (ADRAn) ..................................................................93

Device B Address Counter Register (ADCBn) .....................................................93

Device B Address Register (ADRBn) ..................................................................93

Block Length Counter Register (BLTCn) .............................................................94

Block Length Register (BLTRn) ...........................................................................94

DMA Control Register (DMACNTLn) ...................................................................94

DMA Status Register (DMASTATn) .....................................................................96

4.2.9 Usage Hints .................................................................................................................97

4.3 INTERRUPT CONTROL UNIT (ICU) .........................................................................................98

4.3.1 Features ......................................................................................................................98

4.3.2 Non-Maskable Interrupt (NMI) .....................................................................................98

External NMI Inputs .............................................................................................98

Non-Maskable Interrupt Processing ....................................................................98

PFAIL Input ..........................................................................................................98

4.3.3 Maskable Interrupts .....................................................................................................98

Maskable Interrupt Vectors ..................................................................................99

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PC87591E/S/L

Pending Interrupts ...............................................................................................99

Interrupt Priorities ................................................................................................99

Power-Down Modes ............................................................................................99

External Interrupt Inputs ......................................................................................99

Interrupt Assignment ............................................................................................99

4.3.4 ICU Registers ............................................................................................................101

ICU Register Map ..............................................................................................101

Interrupt Vector Register (IVCT) ........................................................................101

NMI Status Register (NMISTAT) .......................................................................101

Power Fail Interrupt Control and Status Register (PFAIL) .................................102

Interrupt Status Register 0 (ISTAT0) .................................................................102

Interrupt Status Register 1 (ISTAT1) .................................................................103

Interrupt Enable and Mask Register 0 (IENAM0) ..............................................103

Interrupt Enable and Mask Register 1 (IENAM1) ..............................................103

Edge Interrupt Clear Register 0 (IECLR0) .........................................................104

Edge Interrupt Clear Register 1 (IECLR1) .........................................................104

4.3.5 Usage Hints ...............................................................................................................104

Initializing ...........................................................................................................104

Clearing .............................................................................................................104

Nesting ...............................................................................................................104

4.4 MULTI-INPUT WAKE-UP (MIWU) ...........................................................................................105

4.4.1 Features ....................................................................................................................105

4.4.2 Operation ...................................................................................................................105

4.4.3 MIWU Registers ........................................................................................................109

MIWU Register Map ..........................................................................................109

Edge Detection Register (WKEDG1) .................................................................109

Edge Detection Register (WKEDG2) .................................................................110

Edge Detection Register (WKEDG3) .................................................................110

Edge Detection Register (WKEDG4) .................................................................110

Pending Register (WKPND1) ............................................................................110

Pending Register (WKPND2) ............................................................................110

Pending Register (WKPND3) ............................................................................110

Pending Register (WKPND4) ............................................................................111

Enable Register (WKEN1) .................................................................................111

Enable Register (WKEN2) .................................................................................111

Enable Register (WKEN3) .................................................................................111

Enable Register (WKEN4) .................................................................................111

Pending Clear Register (WKPCL1) ...................................................................111

Pending Clear Register (WKPCL2) ...................................................................112

Pending Clear Register (WKPCL3) ...................................................................112

Pending Clear Register (WKPCL4) ...................................................................112

4.4.4 Usage Hints ...............................................................................................................112

4.5 GENERAL-PURPOSE I/O (GPIO) PORTS .............................................................................113

GPIO Port Functionality .....................................................................................113

4.5.1 Features ....................................................................................................................114

4.5.2 GPIO Port Px .............................................................................................................114

Bidirectional Port with Alternate Function ..........................................................114

4.5.3 GPI Port Py ................................................................................................................116

Input Only Port with Alternate Function .............................................................116

4.5.4 GPO Port Pz ..............................................................................................................117

Output Only Port with Alternate Function ..........................................................117

Table of Contents (Continued)

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PC87591E/S/L

4.5.5 GPIO Port Pw ............................................................................................................118

GPIO Port Signals Shared with Development System Signals .........................118

4.5.6 GPIO Port Registers ..................................................................................................119

GPIO Register Map ...........................................................................................119

Port Alternate Function Registers (PxALT, PyALT and PzALT) ........................119

Port Direction Registers (PxDIR and PwDIR) ....................................................120

Port Data Output Register (PxDOUT, PzDOUT and PwDOUT) ........................120

Port Data Input Registers (PxDIN, PyDIN and PwDIN) .....................................120

Port Weak Pull-Up Registers (PxWPU, PyWPU) ..............................................121

4.6 PS/2 INTERFACE ....................................................................................................................122

4.6.1 Features ....................................................................................................................122

4.6.2 General Description ...................................................................................................122

4.6.3 Operating With the Shift Mechanism Disabled ..........................................................124

4.6.4 Operating With the Shift Mechanism Enabled ...........................................................125

Receive Mode ....................................................................................................126

Transmit Mode ...................................................................................................127

4.6.5 PS/2 Interface Registers ............................................................................................128

PS/2 Register Map .............................................................................................129

PS/2 Data Register (PSDAT) .............................................................................129

PS/2 Status Register (PSTAT) ..........................................................................129

PS/2 Control Register (PSCON) ........................................................................130

PS/2 Output Signal Register (PSOSIG) .............................................................131

PS/2 Input Signal Register (PSISIG) .................................................................132

PS/2 Interrupt Enable Register (PSIEN) ............................................................133

4.7 MULTI-FUNCTION 16-BIT TIMER (MFT16) ...........................................................................134

4.7.1 Features ....................................................................................................................134

4.7.2 Clock Source Unit ......................................................................................................135

Pre-Scaler ..........................................................................................................135

External Event Clock .........................................................................................135

Pulse Accumulate Mode ....................................................................................135

Slow-Speed Clock .............................................................................................135

Counter Clock Source Select .............................................................................136

4.7.3 Timer/Counter and Action Unit ..................................................................................136

Operation Modes ...............................................................................................136

Mode 1, PWM and Counter ...............................................................................136

Mode 2, Dual Input Capture ...............................................................................137

Mode 3, Dual Independent Timer ......................................................................138

Mode 4, Input Capture and Timer ......................................................................139

4.7.4 Timer Interrupts .........................................................................................................140

4.7.5 Timer I/O Functions ...................................................................................................141

4.7.6 Operation in Development System ............................................................................141

4.7.7 MFT16 Registers .......................................................................................................142

MFT16 Register Map .........................................................................................142

Timer/Counter Register 1 (TnCNT1) .................................................................142

Reload/Capture Register A (TnCRA) .................................................................142

Reload/Capture Register B (TnCRB) .................................................................142

Timer/Counter Register 2 (TnCNT2) .................................................................143

Clock Pre-Scaler Register (TnPRSC) ................................................................143

Clock Unit Control Register (TnCKC) ................................................................143

Timer Mode Control Register (TnCTRL) ............................................................144

Table of Contents (Continued)

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PC87591E/S/L

Timer Interrupt Control Register (TnICTL) .........................................................145

Timer Interrupt Clear Register (TnICLR) ...........................................................146

4.8 PULSE WIDTH MODULATOR (PWM) ....................................................................................147

4.8.1 Features ....................................................................................................................147

4.8.2 Functional Description ...............................................................................................147

4.8.3 Cycle Time and Duty Cycle Calculation ....................................................................148

4.8.4 Power Modes .............................................................................................................148

4.8.5 PWM Registers ..........................................................................................................148

PWM Register Map ............................................................................................148

Clock Pre-Scaler Register (PRSC) ....................................................................148

Cycle Time Register (CTR) ................................................................................149

Duty Cycle Registers 0 to 7 (DCRi) ...................................................................149

PWM Polarity Register (PWMPOL) ...................................................................150

PWM Control Register (PWMCNT) ...................................................................150

4.9 UNIVERSAL SYNCHRONOUS/ASYNCHRONOUS RECEIVER-TRANSMITTER (USART) ..151

4.9.1 Features ....................................................................................................................151

4.9.2 Functional Overview ..................................................................................................151

4.9.3 Operation ...................................................................................................................153

4.9.4 USART Registers ......................................................................................................158

USART Register Map ........................................................................................158

Receive Data Buffer Register (URBUF) ............................................................158

Transmit Data Buffer Register (UTBUF) ............................................................158

Baud Rate Pre-Scaler Register (UPSR) ............................................................158

Baud Rate Divisor Register (UBAUD) ...............................................................158

Frame Select Register (UFRS) ..........................................................................159

Mode Select Register (UMDSL) ........................................................................160

Status Register (USTAT) ...................................................................................161

Interrupt Control Register (UICTRL) ..................................................................162

4.9.5 Usage Hints ...............................................................................................................162

4.10 TIMER AND WATCHDOG (TWD) ...........................................................................................164

4.10.1 Features ....................................................................................................................164

4.10.2 Functional Description ...............................................................................................164

4.10.3 TWD Registers ..........................................................................................................166

TWD Register Map ............................................................................................166

Timer and WATCHDOG Configuration Register (TWCFG) ...............................166

Timer and WATCHDOG Clock Pre-Scaler Register (TWCP) ............................167

TWD Timer 0 Register (TWDT0) .......................................................................167

TWDT0 Control and Status Register (T0CSR) ..................................................168

WATCHDOG Count Register (WDCNT) ............................................................168

WATCHDOG Service Data Match Register (WDSDM) .....................................168

4.10.4 Usage Hints ...............................................................................................................169

4.11 ANALOG TO DIGITAL CONVERTER (ADC) ..........................................................................170

4.11.1 Features ....................................................................................................................170

4.11.2 Functional Description ...............................................................................................170

4.11.3 Voltage Measurement ...............................................................................................173

4.11.4 Temperature Measurement .......................................................................................173

4.11.5 ADC Operation ..........................................................................................................174

Reset .................................................................................................................174

ADC Clock .........................................................................................................174

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Initializing the ADC ............................................................................................174

Enabling and Disabling the ADC .......................................................................174

Interrupt Structure ..............................................................................................175

ADC Operating Principles ..................................................................................175

Reading Measurement Results .........................................................................176

Failure Detection ................................................................................................177

4.11.6 ADC Registers ...........................................................................................................177

ADC Register Map .............................................................................................177

ADC Status Register (ADCSTS) ........................................................................178

ADC Configuration Register (ADCCNF) ............................................................179

ADC Clock Control Register (ACLKCTL) ...........................................................179

ADC Delay Control Register (ADLYCTL) ..........................................................180

Local Diode Overtemperature Limit Register (TLOCOTL) .................................181

ADC Parameters Index Register (ADCPINX) ....................................................181

ADC Parameters Data Register (ADCPD) .........................................................181

Temperature Channel Control Register (TCHANCTL) ......................................182

Temperature Channel Data Buffer (TCHANDAT) ..............................................182

Voltage Channel 1 Control Register (VCHN1CTL) ............................................183

Voltage Channel 1 Data Buffer (VCHN1DAT) ...................................................184

Voltage Channel 2 Control Register (VCHN2CTL) ............................................184

Voltage Channel 2 Data Buffer (VCHN2DAT) ...................................................184

Voltage Channel 3 Control Register (VCHN3CTL) ............................................185

Voltage Channel 3 Data Buffer (VCHN3DAT) ...................................................185

4.11.7 Usage Hints ...............................................................................................................185

Power Supply and Layout Guidelines ................................................................185

Power Consumption ..........................................................................................185

Back-Drive Protection ........................................................................................185

Measuring Out of Range Voltages .....................................................................185

Filtering the Noise on Voltage Input Signals ......................................................186

Calculating the Voltage Channel Delay .............................................................186

Thermistor-Based Temperature Measurement ..................................................186

Remote Diode Selection ....................................................................................187

Filtering the Noise on Temperature Input Signals .............................................187

Calculating the Temperature Channel Delay .....................................................188

PC Board Layout ...............................................................................................188

Twisted Pair and Shielded Cables .....................................................................189

4.12 DIGITAL TO ANALOG CONVERTER (DAC) ..........................................................................190

4.12.1 Features ....................................................................................................................190

4.12.2 Functional Description ...............................................................................................190

4.12.3 D/A Conversion .........................................................................................................190

Output Signal .....................................................................................................190

Reference Voltage .............................................................................................191

Conversion Time ................................................................................................191

4.12.4 Operation ...................................................................................................................192

Initializing the DAC ............................................................................................192

Enabling and Disabling the DAC .......................................................................192

4.12.5 DAC Registers ...........................................................................................................193

DAC Register Map .............................................................................................193

DAC Control Register (DACCTRL) ....................................................................193

DAC Data Channel 0-3 Registers (DACDAT0-3) ..............................................194

4.12.6 Usage Hints ...............................................................................................................194

Power Consumption ..........................................................................................194

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DAC Output Protection ......................................................................................194

Output Voltage Accuracy ...................................................................................194

Output Settling Time ..........................................................................................195

Filtering Noise on Output Signals ......................................................................195

4.13 ACCESS.BUS (ACB) INTERFACE .........................................................................................196

4.13.1 Features ....................................................................................................................196

4.13.2 Functional Description ...............................................................................................196

“Acknowledge After Every Byte” Rule ................................................................198

4.13.3 Master Mode ..............................................................................................................199

4.13.4 Slave Mode ................................................................................................................201

4.13.5 Power-Down ..............................................................................................................201

4.13.6 SDA and SCL Pin Configuration ................................................................................201

4.13.7 ACB Clock Frequency Configuration .........................................................................202

4.13.8 ACB Registers ...........................................................................................................202

ACB Register Map .............................................................................................202

ACB Serial Data Register (ACBnSDA) ..............................................................202

ACB Status Register (ACBnST) ........................................................................203

ACB Control Status Register (ACBnCST) .........................................................204

ACB Control Register 1 (ACBnCTL1) ................................................................205

ACB Own Address Register (ACBnADDR and ACBnADDR2) ..........................206

ACB Control Register 2 (ACBnCTL2) ................................................................206

ACB Control Register 3 (ACBnCTL3) ................................................................207

4.13.9 Usage Hints ...............................................................................................................207

4.14 ANALOG COMPARATORS MONITOR (ACM) .......................................................................208

4.14.1 Features ....................................................................................................................208

4.14.2 Functional Description ...............................................................................................208

4.14.3 Voltage Level .............................................................................................................209

4.14.4 ACM Operation ..........................................................................................................210

Reset .................................................................................................................210

Sampling Delay ..................................................................................................210

Initializing the ACM ............................................................................................210

Interrupt Structure ..............................................................................................211

ACM Operating Sequences ...............................................................................211

4.14.5 ACM Registers ..........................................................................................................212

ACM Register Map ............................................................................................212

ACM Control and Status Register (ACMCTS) ...................................................213

ACM Configuration Register (ACMCNF) ...........................................................214

ACM Timing Control Register (ACMTIM) ..........................................................215

Comparison Threshold Data Register (THRDAT) .............................................216

Comparison Result Register (CMPRES) ...........................................................216

Voltage Level Data Buffer - Input 0 through 7 (VOLDAT0-7) ............................217

4.14.6 Usage Hints ...............................................................................................................217

Voltage Level Burst ............................................................................................217

4.15 ON-CHIP RAM .........................................................................................................................218

4.16 ON-CHIP FLASH .....................................................................................................................218

4.16.1 Features ....................................................................................................................218

4.16.2 Functional Description ...............................................................................................219

4.16.3 Flash Interface States and Timing Control ................................................................222

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4.16.4 Flash Access and Control ..........................................................................................224

4.16.5 Parallel Flash Interface ..............................................................................................226

4.16.6 Flash Protection .........................................................................................................226

4.16.7 Flash Interface Registers ...........................................................................................228

Information Block Access Index Register (IBAI) ................................................228

Information Block Data Register (IBD) ...............................................................229

Flash Core Write Protect Register 0 (FCWP0) ..................................................229

Flash Memory Control Register (FLCR) ............................................................230

Flash Memory Status Register (FLSR) ..............................................................231

Flash Memory Pre-Scaler Register (FLPSLR) ...................................................231

Flash Memory Start Time Register (FLSTART) .................................................232

Flash Memory Transition Time Register (FLTRAN) ..........................................232

Flash Memory Program Time Register (FLPROG) ............................................232

Flash Memory Page Erase Time Register (FLPERASE) ...................................233

Flash Memory Section Erase Time Register (FLSERASE) ...............................233

Flash Memory End Time Register (FLEND) ......................................................233

Flash Memory Section Erase End Time Register (FLSEND) ............................234

Flash Memory Recovery Time Register (FLRCV) .............................................234

4.17 POWER MANAGEMENT CONTROLLER (PMC) ...................................................................235

4.17.1 Features ....................................................................................................................235

4.17.2 The Core Domain Power Modes ...............................................................................235

4.17.3 Switching Between Power Modes .............................................................................236

Decreasing Power Consumption .......................................................................236

Increasing Activity ..............................................................................................236

Power Mode Switch Protection ..........................................................................237

4.17.4 The Power Management Controller Status Register (PMCSR) .................................237

4.17.5 Usage Hints ...............................................................................................................238

4.18 HIGH-FREQUENCY CLOCK GENERATOR (HFCG) .............................................................239

4.18.1 Features ....................................................................................................................239

4.18.2 Functional Description ...............................................................................................239

4.18.3 HFCG States .............................................................................................................240

PMC Enabled SuperI/O Disabled State .............................................................240

SuperI/O Enabled State .....................................................................................242

4.18.4 The Programmable Pre-Scaler: Core Domain Clock Generation ..............................242

4.18.5 State Transitions ........................................................................................................242

4.18.6 48 MHz Clock Monitor ...............................................................................................243

4.18.7 HFCG Registers .......................................................................................................243

HFCG Register Map ..........................................................................................243

HFCG Control Register 1 (HFCGCTRL1) ..........................................................244

HFCGM Low Value Register (HFCGML) ...........................................................245

HFCGM High Value Register (HFCGMH) .........................................................245

HFCGN Value Register (HFCGN) .....................................................................245

HFCGI Low Value Register (HFCGIL) ...............................................................246

HFCGI High Value Register (HFCGIH) .............................................................246

HFCG Pre-Scaler Register (HFCGP) ................................................................246

HFCG Control Register 2 (HFCGCTRL2) ..........................................................247

4.19 THE DEBUGGER INTERFACE ...............................................................................................248

4.19.1 Features ....................................................................................................................248

4.19.2 Structure ....................................................................................................................248

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4.19.3 Debugger Interface Functional Description ...............................................................249

Rx Data Link ......................................................................................................249

TX Data Link ......................................................................................................250

Debugger Reset Circuit .....................................................................................250

ISE Interrupt Control ..........................................................................................250

Clock Synchronization .......................................................................................251

4.19.4 Flash Interface Functional Description ......................................................................251

4.19.5 Test Access Port (TAP) .............................................................................................253

TAP Signals .......................................................................................................254

TAP Controller ...................................................................................................254

4.19.6 TAP Instruction Register ............................................................................................256

Design and Construction ...................................................................................256

Instruction Register Operation ...........................................................................257

Instructions ........................................................................................................258

Flash Support Instructions .................................................................................258

Debugger Interface Instructions .........................................................................259

4.19.7 TAP Data Registers, Debugger Interface ..................................................................260

Bit Arrangement and Mapping ...........................................................................260

Functionality in Various TAP Controller States ..................................................260

Debug Bypass Register (BYPASS) ...................................................................261

Debug Data Register (DBGDATA) ....................................................................261

Debug Abort Mask Register (DBGMASKS) .......................................................261

4.19.8 TAP Data Registers, Flash Interface .........................................................................262

Flash Control and Status Register (FL_CT_ST) ................................................262

Flash Identification Register (FL_ID) .................................................................263

Flash Address Register (FL_ADDR) ..................................................................264

Flash Data Register (FL_DATA) ........................................................................265

Flash Erase Register (FL_ERASE) ...................................................................266

4.19.9 Core Registers, Debugger Interface ..........................................................................267

Core Register Map .............................................................................................267

Debug Receive Data Registers 0, 2, 4, 6, 8, 10, 12 and 14 (DBGRXD0-14) ....267

Debug Receive Status Register (DBGRXST) ....................................................268

Debug Transmit Data Registers 0, 2, 4, 6, 8, 10, 12 and 14 (DBGTXD0-14) ....268

Debug Transmit Lock Register (DBGTXLOC) ...................................................269

Debug Transmit Status Register (DBGTXST) ...................................................269

Debug TINT Assert Register (DBGTINT) ..........................................................270

Debug Abort Generate Register (DBGABORT) .................................................270

Debug ISE Source Registers A (DBGISESRCA) ..............................................271

4.19.10 Usage Hints ..............................................................................................................271

4.20 DEVELOPMENT SYSTEM SUPPORT ...................................................................................272

4.20.1 Features ....................................................................................................................272

4.20.2 The ISE Interrupt .......................................................................................................272

4.20.3 Break Line and Reset Output Interrupt ......................................................................272

4.20.4 TRIS Strap Input Pin ..................................................................................................272

4.20.5 Freezing Events .........................................................................................................273

4.20.6 Monitoring Activity During Development ....................................................................273

Bus Status Signals .............................................................................................273

Transaction Effect on the External Bus .............................................................274

Pipe Status Signals (PFS and PLI) ....................................................................274

4.20.7 On-Chip Hardware Breakpoint ..................................................................................274

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4.20.8 CR16B Development Support Registers ...................................................................275

Debug Configuration Register (DBGCFG) .........................................................275

Debug Freeze Enable Register (DBGFRZEN) ..................................................276

5.0 Host Controller Interface Modules

5.1 KEYBOARD AND MOUSE CONTROLLER INTERFACE .......................................................277

5.1.1 Features ....................................................................................................................277

5.1.2 General Description ...................................................................................................277

Host Addresses .................................................................................................277

Core Interrupts ...................................................................................................277

Host Interrupts ...................................................................................................277

Keyboard/Mouse Channel (6016, 6416) ............................................................278

Status Read .......................................................................................................279

5.1.3 Host Interface Registers ............................................................................................280

Host Interface Register Map .............................................................................280

Data Out Buffer Register (DBBOUT, Legacy 6016) ..........................................280

Status Register (STATUS, Legacy 6416) ..........................................................281

Data In Buffer Register (DBBIN, Legacy 6016) .................................................281

Command In Buffer Register (COMAND, Legacy 6416) ...................................281

5.1.4 Core Interface Registers ............................................................................................282

Core Interface Register Map ..............................................................................282

Host Interface Control Register (HICTRL) .........................................................282

Host Interface IRQ Control Register (HIIRQC) ..................................................283

Host Interface Keyboard/Mouse Status Register (HIKMST) ..............................284

Host Interface Keyboard Data Out Buffer Register (HIKDO) .............................284

Host Interface Mouse Data Out Buffer Register (HIMDO) .................................285

Host Interface Keyboard/Mouse Data In Buffer Register (HIKMDI) ...................285

5.2 POWER MANAGEMENT (PM) CHANNELS ...........................................................................285

5.2.1 Features ....................................................................................................................285

5.2.2 General Description ...................................................................................................286

Host Addresses .................................................................................................286

Core Interrupts ...................................................................................................287

Host Interrupt Generation Modes ......................................................................287

Status Read .......................................................................................................289

Host Data Read from Host Interface Power Management Channel ..................290

5.2.3 Core PM Registers ....................................................................................................290

Core PM Register Map ......................................................................................291

Host Interface PM n Status Register (HIPMnST) ..............................................291

Host Interface PM n Data Out Buffer (HIPMnDO) .............................................292

Host Interface PM n Data Out Buffer with SCI (HIPMnDOC) ............................292

Host Interface PM n Data Out Buffer with SMI (HIPMnDOM) ...........................292

Host Interface PM n Data In Buffer (HIPMnDI) ..................................................293

Host Interface PM n Data In Buffer with SCI (HIPMnDIC) .................................293

Host Interface PM n Control Register (HIPMnCTL) ...........................................294

Host Interface PM n Interrupt Control Register (HIPMnIC) ................................295

Host Interface PM n Interrupt Enable Register (HIPMnIE) ................................296

5.3 SHARED MEMORY AND SECURITY .....................................................................................297

5.3.1 Host Bus to Core Bus Access Translation .................................................................297

5.3.2 Memory Mapping and Host Address Translation ......................................................297

5.3.3 Indirect Memory Read and Write Transaction ...........................................................300

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5.3.4 Locking Between Domains ........................................................................................300

5.3.5 Host Access Protection .............................................................................................301

Response to a Restricted Access ......................................................................302

5.3.6 Random Number Generator (PC87591S) .................................................................303

5.3.7 Signaling Interface .....................................................................................................303

5.3.8 Shared Memory Host Registers ................................................................................303

Shared Memory Indirect Memory Address Register 0 (SMIMA0) ......................304

Shared Memory Indirect Memory Address Register 1 (SMIMA1) ......................304

Shared Memory Indirect Memory Address Register 2 (SMIMA2) ......................304

Shared Memory Indirect Memory Address Register 3 (SMIMA3) ......................304

Shared Memory Indirect Memory Data Register (SMIMD) ................................305

Shared Memory Host Control Register (SMHC) ................................................305

Shared Memory Host Status Register (SMHST) ...............................................305

Shared Memory Host Access Protect Register 1 and 2 (SMHAP1-2) ...............306

Shared Memory Host Semaphore Register (SMHSEM) ....................................306

5.3.9 Shared Memory Core Registers ................................................................................307

Shared Memory Core Control and Status Register (SMCCST) .........................307

Shared Memory Core Top Address Register (SMCTA) .....................................308

Shared Memory Host Semaphore Register (SMHSEM) ....................................308

Shared Memory Core Override Read Protect Registers 0-2 (SMCORP0-2) .....309

Shared Memory Core Override Write Protect Registers 0-2 (SMCOWP0-2) ....310

Random Number Generator Control/Status Register, RNGCS (PC87591S) ....311

Random Number Generator Data Register, RNGD (PC87591S) ......................312

5.3.10 Usage Hints ...............................................................................................................312

5.4 CORE ACCESS TO HOST-CONTROLLED MODULES .........................................................313

5.4.1 Core Access to Host-Controlled Module Registers ...................................................314

Indirect Host I/O Address Register (IHIOA) .......................................................314

Indirect Host Data Register (IHD) ......................................................................314

Lock SuperI/O Host Access Register (LKSIOHA) .............................................315

SuperI/O Access Lock Violation Register (SIOLV) ............................................315

Core to SIB Modules Access Enable Register (CRSMAE) ................................316

SIB Control Register (SIBCTRL) .......................................................................317

5.5 MOBILE SYSTEM WAKE-UP CONTROL (MSWC) ................................................................318

5.5.1 Features ....................................................................................................................318

5.5.2 Wake-Up Event Detection and Status Bits ................................................................318

5.5.3 Wake-Up Output Events ............................................................................................320

5.5.4 Other MSWC Controlled Elements ............................................................................322

Host Configuration Address Selection ...............................................................322

Host Keyboard Fast Reset .................................................................................322

GA20 Pin Functionality ......................................................................................322

5.5.5 MSWC Host Registers ...............................................................................................323

MSWC Host Register Map .................................................................................323

Wake-Up Event Status Register 0 (WK_STS0) .................................................323

Wake-Up Events Enable Register (WK_EN0) ...................................................324

Wake-Up Configuration Register (WK_CFG) ....................................................325

Wake-Up Signals Value Register (WK_SIGV) ...................................................325

Wake-Up ACPI State Register (WK_STATE) ....................................................326

Wake-Up Event Routing to SMI Enable Register 0 (WK_SMIEN0) ...................327

Wake-Up Event Routing to IRQ Enable Register 0 (WK_IRQEN0) ...................328

5.5.6 MSWC Core Registers ..............................................................................................328

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MSWC Control Status Register 1 (MSWCTL1) .................................................329

MSWC Control Status Register 2 (MSWCTL2) .................................................330

MSWC Control Status Register 3 (MSWCTL3) .................................................330

Host Configuration Base Address Low (HCFGBAL) ..........................................331

Host Configuration Base Address High (HCFGBAH) ........................................331

MSWC Interrupt Enable Register 2 (MSIEN2) ...................................................331

MSWC Host Event Status Register 0 (MSHES0) ..............................................332

MSWC Host Event Interrupt Enable Register (MSHEIE0) .................................333

5.5.7 Usage Hints ...............................................................................................................334

PWUREQ Output Connection ............................................................................334

RESET2 Events .................................................................................................334

6.0 Host-Controlled Modules and Host Interface

6.1 DEVICE ARCHITECTURE AND CONFIGURATION ..............................................................335

6.1.1 Configuration Structure and Access ..........................................................................335

The Index-Data Register Pair ............................................................................335

Banked Logical Device Registers Structure ......................................................336

Standard Logical Device Configuration Register Definitions .............................337

6.1.2 Standard Configuration Registers .............................................................................340

SuperI/O Control and Configuration Registers ..................................................340

Logical Device Control and Configuration Registers .........................................340

Control ...............................................................................................................340

Standard Configuration ......................................................................................341

Special Configuration .........................................................................................341

6.1.3 Default Configuration Setup ......................................................................................341

6.1.4 Address Decoding .....................................................................................................341

6.1.5 Interrupt Serializer .....................................................................................................342

6.1.6 Protection ..................................................................................................................342

6.1.7 LPC Interface .............................................................................................................342

LPC Transactions Supported .............................................................................342

Core Interrupt .....................................................................................................343

CLKRUN Functionality .......................................................................................343

LPCPD Functionality ..........................................................................................343

6.1.8 SuperI/O Configuration Registers ..............................................................................343

SuperI/O ID Register (SID) ................................................................................344

SuperI/O Configuration 1 Register (SIOCF1) ....................................................344

SuperI/O Configuration 5 Register (SIOCF5) ....................................................345

SuperI/O Configuration 6 Register (SIOCF6) ....................................................345

SuperI/O Revision ID Register (SRID) ...............................................................346

SuperI/O Configuration 8 Register (SIOCF8) ....................................................346

SuperI/O Configuration 9 Register (SIOCF9) ....................................................347

SuperI/O Configuration D Register (SIOCFD) ...................................................347

6.1.9 Mobile System Wake-Up Control (MSWC) Configuration .........................................348

Logical Device 4 (MSWC) Configuration ...........................................................348

6.1.10 Keyboard and Mouse Controller (KBC) Configuration ...............................................348

Logical Devices 5 and 6 (Mouse and Keyboard) Configuration .........................348

6.1.11 Shared Memory Configuration ...................................................................................349

Logical Device 15 (0F16) (Shared Memory) Configuration ................................349

Memory Range Programing ...............................................................................350

Shared Memory Configuration Register ............................................................351

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Shared Memory Base Address High Byte Register ...........................................351

Shared Memory Base Address Low Byte Register ............................................352

Shared Memory Size Configuration Register ....................................................352

6.1.12 Real Time Clock (RTC) Configuration .......................................................................353

Logical Device 16 (1016) RTC Configuration .....................................................353

RAM Lock Register (RLR) .................................................................................353

Date Of Month Alarm Register Offset (DOMAO) ...............................................354

Month Alarm Register Offset (MONAO) ............................................................354

Century Register Offset (CENO) .......................................................................354

6.1.13 Power Management Interface Channel 1 Configuration ............................................355

Logical Device 17 (1116) Power Management Channel 1 .................................355

6.1.14 Power Management Interface Channel 2 Configuration ............................................355

Logical Device 18 (1216) Power Management Channel 2 .................................355

6.2 REAL-TIME CLOCK (RTC) .....................................................................................................356

6.2.1 Bus Interface .............................................................................................................356

6.2.2 RTC Clock Generation ..............................................................................................356

6.2.3 Internal Oscillator .......................................................................................................356

6.2.4 External Oscillator .....................................................................................................357

Connections .......................................................................................................357

Signal Parameters .............................................................................................358

6.2.5 Timing Generation .....................................................................................................358

6.2.6 Timekeeping ..............................................................................................................358

6.2.7 Updating ....................................................................................................................359

6.2.8 Alarms .......................................................................................................................359

6.2.9 Power Supply ............................................................................................................360

6.2.10 System Bus Lockout ..................................................................................................361

6.2.11 Power-Up Detection ..................................................................................................361

6.2.12 Oscillator Activity .......................................................................................................362

6.2.13 Interrupt Handling ......................................................................................................362

6.2.14 Battery-Backed RAMs and Registers ........................................................................363

6.2.15 RTC Registers ...........................................................................................................363

Seconds Register (SEC) ....................................................................................364

Seconds Alarm Register (SECA) .......................................................................365

Minutes Register (MIN) ......................................................................................365

Minutes Alarm Register (MINA) .........................................................................365

Hours Register (HOR) .......................................................................................365

Hours Alarm Register (HORA) ...........................................................................366

Day Of Week Register (DOW) ...........................................................................366

Date Of Month Register (DOM) .........................................................................366

Month Register (MON) .......................................................................................366

Year Register (YER) ..........................................................................................367

RTC Control Register A (CRA) ..........................................................................367

RTC Control Register B (CRB) ..........................................................................368

RTC Control Register C (CRC) ..........................................................................369

RTC Control Register D (CRD) ..........................................................................370

Date of Month Alarm Register (DOMA) .............................................................370

Month Alarm Register (MONA) ..........................................................................370

Century Register (CEN) .....................................................................................371

6.2.16 BCD and Binary Formats ...........................................................................................371

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6.2.17 Usage Hints ...............................................................................................................371

6.2.18 RTC General-Purpose RAM Map ..............................................................................371

7.0 Device Specifications

7.1 GENERAL DC ELECTRICAL CHARACTERISTICS ...............................................................372

7.1.1 Recommended Operating Conditions .......................................................................372

7.1.2 Absolute Maximum Ratings .......................................................................................372

7.1.3 Capacitance ..............................................................................................................373

7.1.4 Power Supply Current Consumption under Recommended Operating Conditions ...373

7.1.5 Voltage Thresholds ....................................................................................................373

7.2 DC CHARACTERISTICS OF PINS BY I/O BUFFER TYPES .................................................374

7.2.1 Input, CMOS Compatible with Schmitt Trigger ..........................................................374

7.2.2 Input, PCI 3.3V ..........................................................................................................374

7.2.3 Input, SMBus Compatible ..........................................................................................374

7.2.4 Input, TTL Compatible ...............................................................................................375

7.2.5 Input, TTL Compatible with Schmitt Trigger ..............................................................375

7.2.6 Output, TTL Compatible Push-Pull Buffer .................................................................375

7.2.7 Output, Open-Drain Buffer .........................................................................................376

7.2.8 Output, PCI 3.3V .......................................................................................................376

7.2.9 Exceptions .................................................................................................................376

7.2.10 Terminology ...............................................................................................................376

7.3 INTERNAL RESISTORS .........................................................................................................377

DC Test Conditions ............................................................................................377

7.3.1 Pull-Up Resistor .........................................................................................................377

7.3.2 Pull-Down Resistor ....................................................................................................377

7.4 ANALOG CHARACTERISTICS ...............................................................................................378

7.4.1 ADC Characteristics ..................................................................................................378

Voltage Measurement ........................................................................................378

Temperature Measurement ...............................................................................380

7.4.2 ACM Characteristics ..................................................................................................380

7.4.3 DAC Characteristics ..................................................................................................381

7.5 PACKAGE THERMAL INFORMATION ...................................................................................381

7.6 AC ELECTRICAL CHARACTERISTICS ..................................................................................382

7.6.1 AC Test Conditions ....................................................................................................382

Definitions ..........................................................................................................382

7.6.2 Reset Timing .............................................................................................................384

7.6.3 Clock Timing ..............................................................................................................385

General ..............................................................................................................386

7.6.4 BIU Timing .................................................................................................................388

7.6.5 GPIO Ports Timing ....................................................................................................393

7.6.6 PWM Timing ..............................................................................................................394

7.6.7 MSWC Timing ...........................................................................................................394

7.6.8 PS/2 Interface Timing ................................................................................................395

7.6.9 ACCESS.bus Timing .................................................................................................396

7.6.10 MFT16 Timing ...........................................................................................................399

Table of Contents (Continued)

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PC87591E/S/L

7.6.11 ICU/Development Timing ..........................................................................................400

7.6.12 Asynchronous Edge Detected Signals Timing ..........................................................401

7.6.13 Debugger Interface Timing ........................................................................................402

7.6.14 USART Timing ...........................................................................................................404

7.6.15 LCLK and RESET1-2 ................................................................................................406

7.6.16 LPC and SERIRQ Signals .........................................................................................407

A. Software for Hardware Interface

A.1 CORE DOMAIN REGISTER LIST ...........................................................................................408

A.1.1 Module Configuration ................................................................................................408

A.1.2 Bus Interface Unit (BIU) .............................................................................................408

A.1.3 DMA Controller ..........................................................................................................408

A.1.4 General-Purpose I/O (GPIO) Ports ............................................................................409

A.1.5 PS/2 Ports .................................................................................................................411

A.1.6 Host Interface (KBC, PM1 and PM2Channels) .........................................................411

A.1.7 Multi-Function Timer (MTF16) 1 ................................................................................412

A.1.8 Multi-Function Timer (MFT16) 2 ................................................................................412

A.1.9 Timing and WATCHDOG (TWD) ...............................................................................413

A.1.10 Analog to Digital Converter (ADC) .............................................................................413

A.1.11 Digital to Analog Converter (DAC) .............................................................................413

A.1.12 ACCESS.bus Interface (ACB) 1 ................................................................................414

A.1.13 ACCESS.bus Interface (ACB) 2 ................................................................................414

A.1.14 Analog Comparators Monitor (ACM) .........................................................................414

A.1.15 Power Management (PM) ..........................................................................................415

A.1.16 High Frequency Clock Generator (HFCG) ................................................................415

A.1.17 Development System Support ...................................................................................415

A.1.18 Multi-Input Wake-Up (MIWU) ....................................................................................415

A.1.19 Interrupt Control Unit (ICU) ........................................................................................416

A.1.20 Debugger Interface ....................................................................................................416

A.1.21 Pulse Width Modulator (PWM) ..................................................................................417

A.1.22 Universal Synchronous/Asynchronous Receiver Transmitter (USART) ....................417

A.1.23 Flash Interface ...........................................................................................................418

A.1.24 Shared Memory Core ................................................................................................418

A.1.25 Core Access to SuperI/O ...........................................................................................419

A.1.26 Mobile System Wake-Up Control (MSWC) ................................................................419

A.2 HOST DOMAIN REGISTER LIST ...........................................................................................420

A.2.1 Configuration Registers .............................................................................................420

Common SuperI/O Configuration ......................................................................420

Shared Memory .................................................................................................420

RTC Configuration .............................................................................................420

A.2.2 Host Runtime Registers .............................................................................................420

Shared Memory Host .........................................................................................421

MSWC Host Registers .......................................................................................421

Host Interface (HI) .............................................................................................421

Power Management Channel 1 .........................................................................422

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PC87591E/S/L

Power Management Channel 2 .........................................................................422

RTC ...................................................................................................................422

A.3 CORE DOMAIN REGISTER LAYOUT ....................................................................................424

A.3.1 Module Configuration ................................................................................................424

A.3.2 Bus Interface Unit (BIU) .............................................................................................424

A.3.3 DMA Controller ..........................................................................................................424

A.3.4 General-Purpose I/O (GPIO) Port .............................................................................424

A.3.5 PS/2 Interface ............................................................................................................425

A.3.6 Core Interface ............................................................................................................425

A.3.7 Multi-Function Timer (MFT16) ...................................................................................426

A.3.8 Timing and WATCHDOG (TWD) ...............................................................................426

A.3.9 Analog to Digital Converter (ADC) .............................................................................426

A.3.10 Digital to Analog (DAC) .............................................................................................427

A.3.11 ACCESS.bus Interface (ACB) ...................................................................................427

A.3.12 Analog Comparators Monitor (ACM) .........................................................................427

A.3.13 Power Management (PM) ..........................................................................................427

A.3.14 High-Frequency Clock Generator (HFCG) ................................................................427

A.3.15 Development System Support ...................................................................................427

A.3.16 Multi-Input Wake-Up (MIWU) ....................................................................................427

A.3.17 Interrupt Control Unit (ICU) ........................................................................................428

A.3.18 Debugger Interface ....................................................................................................428

A.3.19 Pulse with Modulator (PWM) .....................................................................................429

A.3.20 Universal Synchronous/Asynchronous Receiver Transmitter (USART) ....................429

A.3.21 Flash Interface ...........................................................................................................429

A.3.22 Shared Memory Core ................................................................................................429

A.3.23 Core Access to SuperI/O ...........................................................................................430

A.3.24 MSWC .......................................................................................................................430

A.4 HOST DOMAIN REGISTER LAYOUT .....................................................................................431

Host Configuration Registers .............................................................................431

A.4.1 SuperI/O Configuration ..............................................................................................431

A.4.2 Shared Memory Configuration ...................................................................................431

A.4.3 RTC Configuration .....................................................................................................431

Host Runtime Registers .....................................................................................431

A.4.4 Shared Memory Host .................................................................................................431

A.4.5 MSWC Host ...............................................................................................................432

A.4.6 Host Interface (HI) Registers .....................................................................................432

A.4.7 RTC Registers ...........................................................................................................432

B. Software for Hardware Interface

B.1 FACTORY PARAMETERS ......................................................................................................434

B.2 PROTECTION INFORMATION ...............................................................................................435

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PC87591E/S/L

1.0 Introduction

1.1 DOCUMENT ORGANIZATION

This document describes the PC87591x architecture and device specifications. It is organized as follows:

Chapter 1,Introduction, provides an overview of PC87591x modules, system connections, operating modes and conﬁgura-

tion.

Chapter 2,Signal/Pin Description and Conﬁguration, lists the PC87591x pins and describes their functions and multiplex-

ing options.

Chapter 3,Power, Reset and Clocks, describes the PC87591x power supplies, clock scheme and reset sequence.

Chapter 4,Embedded Controller Modules, describes the modules that comprise the CompactRISC core peripherals.

Chapter 5, Host Controller Interface Modules, describes the modules and functions that interface core operation with the

host.

Chapter 6,Host-Controlled Modules and Host Interface, deﬁnes the conﬁguration and control functions.

Chapter 7,Device Speciﬁcations, deﬁnes the AC, DC and analog characteristics of the PC87591x.

Appendix A, Summary of Registers, provides a composite listing of all relevant data on core domain registers and summa-

rizes the registers’ layouts.

Appendix B, This section includes directions for the software to handle some predetermined hardware interfaces and pro-

vides details of software-to-hardware interface conventions.

1.2 GENERAL DESCRIPTION

The PC87591x is a highly integrated, embedded controller with an embedded RISC core and system functions. Targeted

for a wide range of portable applications that use the Low Pin Count (LPC) interface, it also features a security system and

host BIOS firmware.

1.2.1 System Connections

Figure 1 shows the system connections of the PC87591x in a typical mobile PC application. The PC87591x requires little, if

any, system glue elements. For a typical application, the PC87591x includes all required memory and peripherals on-chip.

For more complex applications, it allows simple low-cost expansion, using its bus. Some of the features illustrated are mu-

tually exclusive, depending on pin functions.

The major elements of the PC87591x are:

●Embedded Controller (EC) functions, which include: PS/2 devices, keyboard matrix, ACCESS.bus, timers, D/A and

A/D converters and GPIO pins that can be assigned to various functions, as needed. External memory and peripheral

devices may be added to extend the functionality of the on-chip resources.

●Host Processor interface based on the LPC bus and additional signals for interrupts and system power management

●Power Supplies for Host interface functions, EC and backup battery

●Clocks, using a 32.768 KHz crystal and optional clock output

●Strap inputs to initialize the PC87591x to different operation modes

In addition to the wide range of internal peripherals, the PC87591x provides hooks so that the system can be expanded in

an easy and cost-effective manner, as follows:

●I/O expansion to support additional I/O port pins, using low-cost, standard 74HCxx devices or ASICs

●On-chip memories may be expanded to interface with external RAM, ﬂash or ROM devices (176-pin package only).

1.2.2 Power Management

The PC87591x has an advanced power management scheme controlled by the host and/or the PC87591x firmware. The

supported SuperI/O functions may be controlled directly by the host, using ACPI compliant schemes. The EC may also in-

terface with the host via one or two communication channels. Power Management events are available for ACPI-compliant

operation with the respective parts of the host chipset.

The PC87591x is designed to operate as the embedded controller of an ACPI-compliant system. It is equipped with various

system power monitor and control functions and advanced means to control its own power consumption and power modes.

ACPI-compliant wake-up and sleep control is integrated into the PC87591x. These functions are powered by VCC.

1.0 Introduction (Continued)

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PC87591E/S/L

Clock

Expansion

Memory

Host System Bus (LPC Compatible)

32KX1/32KCLKIN

32KX2

LFRAME

LAD0-3

LDRQ

SERIRQ

PWUREQ

WR0, WR1*

SEL0*

A19-8*

D15-8*

AD7-0

DA3-0

IOPA7-0

IOPB7-0

IOPC7-1

IOPD7-4,3-0

RESET-2

RTC

Battery VBAT

Crystal

32.768 KHz

SRAM or

Flash

ENV0

AVCC

AGND

VDD, VCC

GND

Power

Supply

SCL1-2

D7-0

SMI

LPCPD IOPH7-0

IOPE7-0

IOPF7-0

IOPI7-0

CLKRUN

LCLK

EXWINTn

PFAIL

RI1-2, RING

SHBM

I/O

Expansion

TA1-2

BADDR0-1

TRIS

IOPC0

SELIO

SDA1-2

TB1-2

SWIN

Analog/

System

ENV1

Figure 1. PC87591x System Connection Diagram, 128-Pin and 176-Pin Packages

ADC

DAC

Functions

that use:

GPIO

Timers

Interrupts

Ring Wake-Up

On Control

Conﬁguration

Inputs

(Power-Up)

Digital

32KOUT/CLKOUT/CLK

Diode

PWM7-0

On Switch

IOPJ7-2*

IOPK7-0*

URXD, UTXD, USCLK USART I/F

A7-0

CPU/Remote

PC87591x

Key:

*= Available only in

176-pin package

ACCESS.bus

PSCLK1

PSDAT1

External Keyboard

PSCLK2

PSDAT2

PSCLK3

PSDAT3

External Mouse Auxiliary PS/2

Interface

PSCLK4

PSDAT4

ECSCI

KBRST

KBSOUT15-0

KBSIN7-0

Internal

Keyboard

Matrix

GA20

(Optional

in ‘E’& ‘S’)

IOPL4-0*

IOPM7-0*

IOPJ1-0

1.0 Introduction (Continued)

Revision 1.07 25 www.national.com

PC87591E/S/L

The Keyboard Controller and the EC functions (core and associated peripherals) are powered by VCC, which remains active

as long as the system has a power source (e.g., main battery or outlet). Using VCC, the core may be programed to monitor

and control the system even when the host processor is turned off. To support this, the PC87591x is equipped with advanced

means to control its power consumption: software controlled clock frequency throttling, the ability to disable modules, and

four power modes. These power modes include:

●Active Mode - Full functionality

●Active Mode Executing WAIT Instruction - Core execution and associated operations (such as memory access) are suspended

●Idle - Main clock is stopped, but the device can be woken up by internal or external events. The system tick timer is

still operational and can be used to periodically wake up the device.

●Power Off - VCC is absent and only backup battery is available to supply the Real Time Clock (RTC) and retain the

state of some memory and conﬁguration elements.

1.2.3 Operating Environments

The PC87591x can operate in one of the following four environments:

●Internal ROM Enabled (IRE). Used while the PC87591x operates in the production system and executes the appli-

cation. The on-chip ﬂash or ROM is the main source of code for the device.

●On-Board Development (OBD). Used to debug the PC87591x code while it is mounted on its ﬁnal production board.

All pins have their IRE functionality. Interface to a debugger (running on the host) is through the JTAG-based debug-

ger interface. OBD environment is binary and cycle-by-cycle compatible with IRE environment.

●Development (DEV). Used in Application Development Boards (ADB) or In System Emulators (ISE). In this environ-

ment, the on-chip ﬂash or ROM is replaced with off-chip SRAM memory to allow ﬂexible and fast development of ap-

plication code. Some pins are allocated to development system use, and the GPIO functions associated with them

are replicated using off-chip logic as part of the ADB system. DEV environment is binary and cycle-by-cycle compat-

ible with OBD and IRE environments.

●Programing (PROG). Used to program the on-chip ﬂash in parallel programers. No other operation is possible in this

environment.

1.3 INTERNAL ARCHITECTURE

The PC87591x consists of several main components divided into three groups:

●Core Domain

—CR16B core processing unit

—Bus Interface Unit and Memory Controller (BIU)

—RAM and ﬂash memory

—Core peripherals

●Host Domain

—Host-Controlled functions

—Host Interface

●Host-Controller Interface

The descriptions below detail the functions of the various blocks shown in Figure 2.

1.0 Introduction (Continued)

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PC87591E/S/L

Figure 2. PC87591x Functional Block Diagram

1.3.1 Processing Unit

The CompactRISC CR16B core (referred to in this datasheet as the “core”) is an advanced, general-purpose 16-bit micro-

processor core with a RISC architecture. The core is responsible for arithmetic and logic operations, as well as program

control.

For more details about the core structure and instruction set, see CR16B Programmer’s Reference Manual, Revision 2.2,

September 1999 (Literature Number: 633150-001)

1.3.2 Bus Interface Unit and Memory Controller (BIU)

The BIU enables access to off-chip memory and I/O devices. It is organized in zones, as follows:

●Zone 0 - Expansion Memory (ﬂash and/or SRAM). This memory may be used for the core code, data and/or the host

BIOS program.

●Zone 1 - This zone is available for off-chip in DEV environment only and is used for emulating the operation of the

off-chip base memory, using an off-chip SRAM. In IRE and OBD environments, the conﬁguration of this zone should

be the same as in DEV environment to enable cycle-by-cycle compatibility.

The Base memory is partitioned into two zones, fast and slow. The access time to the fast zone is defined by the con-

figuration registers of Zone 1 in the BIU. The access time to the slow zone is defined by the configuration registers of

Zone 2 in the BIU. Only one chip select signal is used—the AND of the two BIU select outputs.

●I/O Zone - This zone can be used for I/O expansion. In DEV environment, it can be used to recreate GPIO signals,

whose pins are used for the development system interface.

Configuration registers that control the bus transactions are associated with each zone and are part of the BIU module, See

Section 4.1 on page 69 for details. For details about the link between DEV environment and the BIU, see Section 1.4.3 on

page 30.

1.3.3 On-Chip Memory

RAM. The 2048/4096-byte on-chip RAM is mostly used for the storage of program variables and the stack. It can also store

short programs used while the flash memory is being updated. Part of the on-chip RAM is reserved for use by the core de-

velopment tools monitor program, TMON. For information, see the CompactRISCPC87591x Tmonlib Version 3.1.2.3 Re-

lease Letter, March 2001,

Flash. The PC87591E and PC87591S are equipped with a large on-chip flash. This flash includes a main block and an in-

formation block. The flash main block is also referred to as on-chip Base Memory and may be used to store core code and

constant data.

Core Bus

Peripheral Bus

Bus

KBC + PM

Host I/F

RTC

Processing

Unit

RAM

External

BIU

CR16B Core

32.768 KHz

ICU

HFCG

PMC

ADC

ACB

GPIO WDG

FLASH or ROM

MIWU

Memory + I/O

MFT16

Timer +

Adapter

PS/2

I/F

(X2)

CLK DAC

(X2)

Memory

Debugger

I/F

Shared mem.

+ Security

LPC

I/F Serial

IRQ SMI

Functions

Internal Bus

CR Access

DMA

JTAG

KBSCAN +

ACM USART

Peripherals

LPC Bus I/F

I/F Functions

PWM

Reset &

Config

MSWC

Bridge

Controlled

Host

1.0 Introduction (Continued)

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PC87591E/S/L

The PC87591x hardware arbitrates flash usage by the core firmware and the host processor BIOS program when Shared-

BIOS configuration is selected. Flash sharing is based on in-parallel “cycle stealing” so both the host processor and the core

can execute code in parallel from the same memory device. The host processor typically copies the flash contents to the

host’s main memory (DRAM) on system boot to improve access time to it and enable execution when the flash’s contents

is compressed. It is important to do this early in the boot process to reduce resource contention between the core and the

host.

The PC87591E and PC87591S flash memory may be updated by the core firmware, host software, JTAG protocol or via the

parallel interface. Protection mechanisms limit the read, write and erase rights of various sources to guarantee flash content

integrity and confidentiality, where applicable. See Section 4.16.6 on page 226 for more details about the flash update and

protection mechanisms.

In DEV environment, access to the main block of the flash is disabled and replaced by off-chip SRAM to enable easy and

efficient debugging. For operation in OBD environment, the application should be linked with the TMON program and loaded

into the on-chip flash. See the CompactRISCPC87591x Tmonlib Version 3.1.2.3 Release Letter, March 2001, for infor-

mation on TMON program integration and specification of requirements.

The PC87591L is equipped with a small pre-programed flash, which functions as a boot ROM. The devices are shipped pre-

programed and may not be programed in the field. Some devices intended for development purpose may be programed via

the JTAG interface.

The information block of the flash has two dedicated areas: one for factory parameters and another for the protection word.

The factory parameters are saved during the device production and are used for various calibrations (see Appendix B.1 on

page 434 for the factory parameters block organization and usage). The protection word holds information on access rights

to the flash and the size of the core and host boot blocks. See Section 4.16.6 on page 226 and Appendix B.2 on page 435

for more information.

1.3.4 Peripherals

The ICU (Interrupt Control Unit) collects interrupts from various internal and external (through the MIWU) sources and no-

tifies the core of the event using the vectored interrupt mechanism. It supports 31 maskable interrupt inputs (see Table 16

on page 99 for the interrupt assignment) and a non-maskable interrupt (NMI) through the PFAIL input.

The MIWU (Multi-Input Wake-Up) module enables collecting various internal and external interrupt sources (events), gen-

erates interrupts in Active mode and enables the PC87591x to return from Idle mode to Active mode. The core can individ-

ually enable or disable the various wake-up conditions. The PC87591x has a total of 28 wake-up signals, some of which are

grouped to generate a single interrupt signal to the ICU.

The PMC (Power Management Controller) controls PC87591x power consumption according to the required activity level.

Power consumption is adjusted by controlling the clock frequency and selective enabling/disabling of three power modes:

Active, Idle and Power Off. Activity can be resumed by external events (through the MIWU) or internal events, such as a

periodic wake-up.

The Clock Generator provides clocks for the various core-related on-chip modules. These clocks are generated directly

from a 32.768 KHz crystal or from the on-chip High-Frequency Clock Generator (HFCG). The HFCG generates the high-

frequency clock using the RTC’s 32.768 KHz clock signal as a reference. The PC87591x operation frequency is set by pro-

graming the HFCG registers. The PMC enables and disables high-frequency clock generation, according to the required

power mode.

The GPIO Ports (General-Purpose Input/Output) module consists of up to 117 GPIO signals (84 in the 128-pin package)

that provide interface and control for the PC system. Some of these I/O port signals share their pins with an alternate function

(see Table 8 on page 54) and may be mutually exclusive. When configured as inputs, some of these signals can interrupt

the core when an event is detected, even if the device is in Idle mode. An example is the SWIN input, which is dedicated to

the PC On/Off switch.

Internal keyboard scanning is supported by 16 open-drain output signals and eight input signals. Switch-based keyboard

matrices are supported with CMOS Schmitt trigger inputs with internal pull-up resistors. Resistive keyboard matrices are

supported with analog comparator inputs with variable thresholds and optional internal pull-up resistors. Section 4.14 on

page 208 describes the functionality of the analog comparator (ACM) circuitry. For power efficiency, the inputs include an

interrupt and a wake-up capability, so that pressing/releasing keys may be identified without scanning the keyboard matrix

in either Active or Idle modes. The keyboard interrupt is controlled by the MIWU.

The PS/2 Interface enables interface with industry-standard, PS/2-compatible keyboard, mouse and other pointing devic-

es. The PC87591x supports up to four PS/2 devices via its dedicated 4-channel PS/2 interface module. Each channel has

two quasi-bidirectional signals. The symmetric structure of the channels enables software-controlled interchanging of devic-

es to channels.

The PC87591x includes a hardware accelerator, which allows the PS/2 channels to be controlled with minimal software

overhead. It also eliminates the sensitivity to interrupt latency that characterized traditional solutions.

1.0 Introduction (Continued)

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PC87591E/S/L

The ACB Interface is a two-wire serial interface compatible with the ACCESS.bus physical layer. It is also compatible with

Intel’s SMBus and Philips’ I2C. This module can serve as a bus master or slave and performs both transmit or receive op-

erations. As a slave, it can respond to two assigned addresses, a global call address and an SMBus ARP address.

The PC87591x includes two ACB Interface modules to allow operation on two isolated buses in the system.

The USART (Universal Synchronous Asynchronous Receiver Transmitter) gives full-duplex support for a wide range of

software programmable baud rates and data formats. It handles automatic parity generation and several error detection

schemes. It also supports DMA transfers to allow for fast processor-independent receive and transmit. It implements flow

control logic to provide the capability for hardware handshaking.

The MFT16 (Multi-Function 16-Bit Timer) contains two 16-bit timers with a range of operation modes. These timers can op-

erate, using several clock sources, in PWM, Capture or Counter mode to satisfy a wide range of application requirements.

The PC87591x includes two MFT16 modules, each of which may be assigned to functions and configured independently.

The TWD (Timer and WATCHDOG) module has a 16-bit periodic interrupt timer that can be programed to generate inter-

rupts at pre-defined intervals and an 8-bit WATCHDOG timer that can reset the PC87591x whenever the software loses

control of the processor.

The periodic timer is typically used as a system tick timer. This timer is fed by the 32.768 KHz clock. Thus its counting is not

impacted by the setting of the HFCG, and it may continue to operate even in Idle mode. This enables it to serve as a periodic

wake-up source during Idle mode.

The PWM (Pulse Width Modulator) module provides eight modulated outputs. The output signals have the same program-

mable frequency and individually-controlled duty cycles.

The ADC (Analog to Digital Converter) provides the PC87591x with an accurate means for measuring slow changing volt-

ages and temperature. The ADC module can measure up to ten external and four internal voltages with 10-bit resolution

over a voltage range of 0 to 2.97V. It can measure temperature using thermistors or perform diode-based temperature mea-

surement. Special circuits are provided to allow accurate measurement of temperature, based on the voltage drop on the

diode junction. This technique is tuned for measuring the temperature of processors with an internal diode.

The DAC (Digital to Analog Converter) has four channels of voltage output. Each of the four DAC channels has an 8-bit res-

olution with a full output range from AGND to AVCC. The DAC provides a settling time of about 1 µs on a 50 pF load.

The Debugger Interface module provides a JTAG-based interface to a remote, host-based debugger. This interface en-

ables device debugging while in OBD environment (i.e., in the final production board) or in DEV environment once in the

development system. The Debugger Interface module uses the JTAG interface to enable programing of the on-chip flash in

both these environments.

1.3.5 Host-Controller Interface Modules

Chapter 5 on page 277 describes a set of modules that resides in the boundary between the host-controlled functions and

the core-controlled functions. These modules are used for message communication, data exchange, memory access and

generating power management events to the host. Chapter 5 also discusses the mechanism that enables the core to access

the host-controlled peripherals.

The Keyboard Controller, Power Management module has three channels that are available for keyboard and power

management (EC)-related host-controller communication.

The keyboard and mouse data channel (i.e., host legacy I/O addresses 6016 and 6416) is compatible with the legacy inter-

face of keyboard controllers. It may be used with polling or interrupts. For use with interrupts, the module can generate the

two legacy IRQ signals: IRQ1 and IRQ12. In addition, the PC87591x generates the gate A20 control signal (GA20 pin) and

a soft reset signal (KBRST pin) to the host. Optionally, this KBRST reset signal can be used to prevent the host from ac-

cessing the shared flash when the PC87591x cannot perform the shared memory access during PC87591x boot-up. See

“GA20 Pin Functionality” on page 322 and “Host Keyboard Fast Reset” on page 322 for details).

The PC87591x supports three Power Management channels, compliant with ACPI requirements for Embedded Controller

(EC) interface. This enables the PC87591x to implement an EC interface that operates in either shared or private modes.

The number of Power Management channels in use and the addresses they respond to (i.e., legacy host I/O addresses 6216

and 6616) are configured in the Host Controlled Functions configuration space. These channels may generate IRQ, SMI or

SCI events to the host. The Power Management channels include a PC87570-compatible mode and an enhanced scheme

that enables more efficient control by the core.

Shared Memory and Security is supported between the host and the core. This sharing may be used for the support of a

shared BIOS scheme, secured information storage and/or for the PC87591x firmware update by the host. The base memory

of the PC87591x and, if needed, the expansion memory can be used as shared memory. The use of the Expansion memory

is optional. The Shared Memory module provides means for the host to access the shared memory. It can also secure ac-

cess to portions of the shared memory for read and/or write operations to allow reliable and tamper-protected storage and

secured update. In addition (PC87591S only), this module includes a random number generator (RNG) that provides hard-

ware-generated random numbers to the core.

1.0 Introduction (Continued)

Revision 1.07 29 www.national.com

PC87591E/S/L

The Mobile System Wake-Up module includes various system wake-up and power management services that may be

handled either by the host or the core. ¨(wake-upsources may be the RTC or external events such as ring detection on the

RING input or modem RI inputs. The module provides hooks for ACPI-compliant drivers, which enable the drivers to handle

wake-up events, change the system power state (including turning it off) and interface to the core firmware. Mask bits can

be enabled to determine whether the core or the host handles each one of the events. In addition, this module provides sta-

tus information about the host domain (e.g., reset input state and VDD supply status).

The Core Access to Host-Controlled Peripherals module enables core access to SuperI/O modules. It can interleave us-

age of a module with the host or take control of it and prevent any host access to that module.

1.3.6 Host-Controlled SuperI/O Modules and Host Interface

The Host Interface is based on Intel’s Low Pin Count (LPC) interface, as defined in LPC Interface Specification, Revision

1.0. This interface enables the host to perform read and write cycles using I/O space accesses and memory space accesses

and FWH transactions. Interrupts are sent to the host, using the serial IRQ protocol.

The PC87591x supports the advanced power management features of the LPC bus. The SMI signal may be sent to interrupt

the host and put it in System Management Mode (SMM). The PWUREQ signal may be connected to one of the wake-up

inputs of the host chipset and used to trigger an SCI event for various EC communication purposes. The PC87591x can

operate with a slowed down or stopped LPC clock and can re-start the LPC clock as part of the system power management

capabilities, using the CLKRUN signal. The LPCPD input enables turning off LPC bus supply while the PC87591x and some

Host Controlled functions are operating.

Host Conﬁguration. The PC87591x includes seven logical devices, each with associated configuration registers, in addi-

tion to a set of global configuration registers.

The central configuration register set supports ACPI-compliant PnP configuration. The configuration registers are structured

as a subset of the Plug and Play Standard registers defined in Appendix A of the Plug and Play ISA Specification, Revision

1.0a by Intel and Microsoft. All system resources assigned to the functional blocks (I/O address space and IRQ lines) are

configured in and managed by the central configuration register set. In addition, some function-specific parameters are con-

figurable through the configuration registers and distributed to the functional blocks through special control signals.

The RTC (Real Time Clock) has a low-power timekeeping mechanism that provides a time-of-day, year-2000-compatible

calendar with a century counter and alarm features. It can work from either VCC or a backup battery, using an internal switch.

Other features include three maskable interrupt sources and 242 bytes of general-purpose RAM. An external battery source

maintains valid RAM and time during VCC failure. The RTC is software compatible with the DS1287 and MC146818.

1.4 OPERATING ENVIRONMENTS

On power-up reset, the ENV1-0 and TRIS input signals select one of the following operating environments:

●Internal ROM Enabled (IRE)

●On Board Development (OBD)

●Development (DEV)

●Programing (PROG)

See Section 2.3 on page 53 for more information about these pins and controlling the loads connected to them.

Code written for IRE environment is executable in all environments, since it is binary compatible. The execution time of code

in on-chip Base Memory (in IRE environment) is identical to that in OBD and DEV environments; i.e., the operation is cycle-

by-cycle compatible.

PC87591x devices are tested to ensure that they operate in either IRE or OBD environment. Only selected parts are tested

for operation in DEV environment.

1.4.1 IRE Environment

IRE environment is used while the PC87591x operates in the production system and executes the application. The on-chip

flash (ROM in PC87591L) is the main source of code for the device. In this environment, after reset, the PC87591x starts

running the code written in the internal flash first address, which is part of the flash’s core boot block. In PC87591E and

PC87591S the core boot-code size may vary from 4 Kbytes to128 Kbytes, as defined in the protection word. To prevent ex-

ecution from non-programed flash (typically due to interrupted update), the code in the boot sector should verify the validity

of the information in other parts of the flash. Once this is successfully done, the core may start executing from these parts

as well. The External Memory, if available, can also be used to store code and/or data.

The PC87591L is shipped with 4 Kbytes of on-chip boot code. The user is expected to use an external memory for most of

the code and constant data.

To maximize on-chip flash (ROM) performance, configure the BIU as described in Section 4.1.11 on page 86 and

Section 4.16.2 on page 219.

1.0 Introduction (Continued)

www.national.com 30 Revision1.07

PC87591E/S/L

See Figure 1 on page 24 for a system example in IRE environment. In this environment, the ENV0, ENV1 and TRIS strap

pins do not need any external pull-up resistors.

1.4.2 OBD Environment

OBD environment is used for debugging the PC87591x firmware while it is mounted on its final production board. All pins

have their IRE functionality, and the interface to a debugger running on the host is enabled using the JTAG based debugger

interface. In OBD Environment, code is executed from the on-chip flash memory. Breakpoints on data and code access may

be applied using the core hardware breakpoint mechanism. The monitor stored in the on-chip flash is used as part of the

debugging environment. Erasing and reprograming the flash is enabled through the JTAG-based debugger interface.

OBD environment is binary and cycle-by-cycle compatible with IRE environment.

See Figure 3 on page 31 for a system example in OBD environment. In this environment, the ENV0 and TRIS strap pins are

left unconnected, and ENV1 requires an external pull-up resistor. If the flash Contents Protect bit in the protection word is

cleared (0), the PC87591x remains reset until the bit is set; see Section 4.16.6 on page 226.

1.4.3 DEV Environment

DEV environment is used in Application Development Boards (ADBs) or In System Emulators (ISEs). It may only be used

when the chip is packed in its 176-pin package. In this mode, the on-chip flash is replaced with off-chip SRAM memory to

allow flexible and fast development of application code. Some pins are allocated for development system use, and the GPIO

functions associated with the pins are replicated using off-chip logic as part of the ADB system. DEV environment is binary

and cycle-by-cycle compatible with OBD and IRE environments.

In this environment, the pins of ports PH, PI, PJ, PK, PL and PM are allocated for the interface to the off-chip Base Memory,

core status signals, reset output and a breakpoint input. The system may regain these ports using the I/O Expansion protocol

and off-chip logic, while maintaining cycle-by-cycle and binary compatibility with IRE and OBD environments. Using the

same software, this environment is binary and cycle-by-cycle compatible with IRE and OBD environments. All features of

IRE environment can be implemented either directly or by using additional external logic.

See Figure 4 on page 32 for a system example in DEV environment. In this environment, the ENV0 strap pin needs an ex-

ternal pull-up resistor and the ENV1 and TRIS pins are left unconnected. If the flash Contents Protect bit in the protection

word is cleared (0), the PC87591x remains reset until the bit is set; see Section 4.16.6 on page 226.

1.4.4 PROG Environment

PROG environment is used to program the on-chip flash. It can be used to program the on-chip flash with an external flash

programer. In PROG environment, the PC87591x remains reset indefinitely, I/O pins are allocated for the on-chip flash in-

terface ports and the on-chip flash interface is accessible directly through the I/O pins.

In this environment, both ENV0 and ENV1 strap pins need an external pull-up resistor. The TRIS pin can be either left un-

connected or connected to a pull-down resistor.

1.5 MEMORY MAP

ThePC87591xhas two address domains: core and host. The host address space is composed of the host I/O address space

and the host memory space. Section 1.5.1 discusses the mapping of memories and peripherals into the core address space.

Figure 5 illustrates the memory map and the shared access schemes that are possible. Section 1.5.2 discusses the mapping

of the host address space and ways of accessing it. The PC87591x enables several memories in the core address space

to have restricted access to the host. These memories are referred to as “shared memory” or “shared BIOS”. In addition, the

core can access the Host Controlled Functions. Section 1.5.2 and Section 1.5.3 discuss these instances of cross-domain

access, respectively.

1.0 Introduction (Continued)

Revision 1.07 31 www.national.com

PC87591E/S/L

TCK

TMS

ENV0

ENV1

VCC R1

TDI

TDO

TINT

Clock

Host System Bus (LPC Compatible)

32KX1/32KCLKIN

32KX2

LFRAME

LAD0-3

LDRQ

SERIRQ

PWUREQ

WR0, WR1*

SEL0*

A19-8*

D15-8*

AD7-0

DA3-0

IOPA7-0

IOPB7-0

IOPC7-1

IOPD7-4,3-0

RESET(1-2)

RTC

Battery VBAT

Crystal

32.768 KHz

AVCC

AGND

VDD, VCC

GND

Power

Supply

SCL1-2

D7-0

SMI

LPCPD IOPH7-0

IOPE7-0

IOPF7-0

IOPI7-0

CLKRUN

LCLK

EXWINTn

PFAIL

RI1-2, RING

SHBM

I/O

Expansion

TA1-2

BADDR0-1

TRIS

IOPC0

SELIO

SDA1-2

TB1-2

SWIN

Analog/

System

Figure 3. OBD Environment PC87591x System Connection Diagram, 128-Pin and 176-Pin Packages

ADC

DAC

Functions

that use:

GPIO

Timers

Interrupts

Ring Wake-Up

On Control

Conﬁguration

Inputs

(Power-Up)

Digital

32KOUT/CLKOUT/CLK

Diode

CPU/Remote

PWM7-0

On Switch

IOPJ7-2*

IOPK7-0*

URXD, UTXD, USCLK USART I/F

A7-0

Key:

*= Available only in

176-pin package

JTAG I/F

Debugger

PC87591x

ACCESS.bus

PSCLK1

PSDAT1

External Keyboard

PSCLK2

PSDAT2

PSCLK3

PSDAT3

External Mouse Auxiliary PS/2

Interface

PSCLK4

PSDAT4

ECSCI

KBRST

KBSOUT15-0

KBSIN7-0

Internal

Keyboard

Matrix

GA20

Expansion

Memory

SRAM or

Flash

(Optional

in ‘E’& ‘S’)

IOPL4-0*

IOPM7-0*

IOPJ1-0

1.0 Introduction (Continued)

www.national.com 32 Revision1.07

PC87591E/S/L

WR1-0

SEL0

A19-0

D15-8

TCK

D7-0

TMS

TDI

TDO

TINT

ENV0

ENV1

VCC

BRKL_RST

BST2-0

PFS

PLI

BE1,0

CBRD

WR1-0

A19-0

D15-0

SELIO

SEL1

Clock

Host System Bus (LPC Compatible)

32KX1/32KCLKIN

LFRAME

LAD0-3

LDRQ

SERIRQ

PWUREQ

AD7-0

DA3-0

IOPA7-0

IOPB7-0

IOPC7-1

IOPD7-0

RESET(1-2)

RTC

Battery VBAT

Crystal

32.768 KHz

AVCC

AGND

VDD, VCC

GND

Power

Supply

SCL1-2

SMI

LPCPD

IOPE7-0

IOPF7-0

CLKRUN

LCLK

EXWINTn

PFAIL

RI1-2, RING

SHBM

TA1-2

TRIS

IOPC0

SDA1-2

TB1-2

SWIN

Analog/

System

Figure 4. DEV Environment PC87591x System Connection Diagram,176-Pin Package

ADC

DAC

Functions

that use:

GPIO

Timers

Interrupts

Ring Wake-Up

On Control

Conﬁguration

Inputs

(Power-Up)

Digital

32KOUT/CLKOUT/CLK

Diode

CPU/Remote

PWM7-0

On switch

URXD, UTXD, USCLK USART I/F

BADDR0-1

32KX2

JTAG I/F

Debugger

Development

Support

I/O

Expansion

Restored

Ports

Off-chip

Base

(Flash emul.

using SRAM)

Memory

CLK

PC87591x

ACCESS.bus

PSCLK1

PSDAT1

External Keyboard

PSCLK2

PSDAT2

PSCLK3

PSDAT3

External Mouse Auxiliary PS/2

Interface

PSCLK4

PSDAT4

ECSCI

KBRST

KBSOUT15-0

KBSIN7-0

Internal

Keyboard

Matrix

GA20

Expansion

Memory

SRAM or

Flash

(Optional

in ‘E’& ‘S’)

1.0 Introduction (Continued)

Revision 1.07 33 www.national.com

PC87591E/S/L

1.5.1 Core Address Domain Memory Map

The memory and I/O devices are directly mapped into the 2 Mbyte address space of the core. The core address space can

include both code and data. However, access to data stored in the first 64 Kbytes of the address space is more efficient.

Most of the core code and constant data (including its boot section) is stored in the Base Memory. This memory is:

●On-chip ﬂash in IRE and OBD environments

●Off-chip memories (SRAM or ﬂash memory) in DEV environment

External memory may be added to the Base Memory to expand the amount of memory available for the application. The on-

chip RAM and various peripherals are also mapped into the core address space.

Tables 1 to 3 show how the PC87591x memory and I/O devices are mapped in the core address space. Appendix A on

page 408 shows the address map of the registers for the other modules.

Addresses not included in the following three tables or Appendix A are reserved. Attempts to access reserved addresses

produce unpredictable results.

Table 1. PC87591S Memory Map

Address Size

(Bytes) Description

Purpose Environment

00 000016 −00 DFFF16 56K Base Memory IRE & OBD - Internal Flash

DEV - External Base Memory

00 E80016 −00 F7FF16 4K System RAM

00 F88016 −00 F8FF16 Flash Control Registers1

00 F90016 −00 F90A16 11 Shared BIOS and Security Registers1

1. See Appendix A on page 408 for details of the implemented registers.

00 F98016 −00 F98F16 16 BIU Registers1

00 FA0016 −00 FA7F16 DMA Controller Registers11

00 FB0016 −00 FBFF16 256 I/O Expansion

00 FC0016 −00 FFFF16 1K On-chip Module Registers1

01 000016 −01 FFFF16 64K Base Memory (cont.) IRE & OBD - Internal ﬂash

DEV - External Base Memory

02 000016 −0F FFFF16 896K Reserved IRE & OBD

Base Memory DEV - External Base Memory

10 000016 −1F FFFF16 1024K Expansion Memory2

2. Available in 176-pin package only.

Figure 5. PC87591x Memory Domains

64K

Mem

Space

Core Address Domain

Host Address Domain

Host Domain Memory

Core Access to Host

End of Flash

External

Memory

Expansion

I/O

Space Controlled Functions 0

2M External

Memory

Expansion

External

Memory

Expansion

PC87591L

PC87591E

PC87591S

(End of Core Memory

Wrap-Around 2M)

1.0 Introduction (Continued)

www.national.com 34 Revision1.07

PC87591E/S/L

Table 2. PC87591E Memory Map

Table 3. PC87591L Memory Map

The following abbreviations are used to indicate the Register Type:

●R/W= Read/Write

●R= The Read portion of a register, where a read from a speciﬁc address returns the value of a speciﬁc register; a

write to the same address is to a different register.

●W= The Write portion of a register as described above for ‘R’.

●RO= Read Only

●WO= Write Only

●R/W1C= Read/Write 1 to Clear. Writing 1 to a bit clears it to 0. Writing 0 has no effect.

Address Size

(Bytes) Description

Purpose Environment

00 000016 −00 DFFF16 56K Base Memory IRE & OBD - Internal Flash

DEV - External Base Memory

00 F00016 −00 F7FF16 2K System RAM

00 F88016 −00 F8FF16 Flash Control Registers1

00 F90016 −00 F90A16 11 Shared BIOS and Security Registers1

1. See Appendix A on page 408 for details of the implemented registers.

00 F98016 −00 F98F16 16 BIU Registers1

00 FA0016 −00 FA7F16 DMA Controller Registers11

00 FB0016 −00 FBFF16 256 I/O Expansion

00 FC0016 −00 FFFF16 1K On-chip Module Registers1

01 000016 −0F FFFF16 960K Reserved IRE & OBD

Base Memory DEV - External Base Memory

10 000016 −1F FFFF16 1024K Expansion Memory2

2. Available in 176-pin package only.

Address Size

(Bytes) Description

Purpose Environment

00 000016 −00 0FFF16 4K Base Memory IRE & OBD - Internal Flash

DEV - External Base Memory

00 100016 −00 DFFF16 52K Expansion Memory 1

1. The Expansion Memory size is limited to 1 Mbyte and is aliased between addresses above and

below 01 000016.

00 F00016 −00 F7FF16 2K System RAM

00 F88016 −00 F8FF16 Flash Control Registers1

00 F90016 −00 F90A16 11 Shared BIOS and Security Registers2

2. See Appendix A on page 408 for details of the implemented registers.

00 F98016 −00 F98F16 16 BIU Registers1

00 FA0016 −00 FA7F16 DMA Controller Registers11

00 FB0016 −00 FBFF16 256 I/O Expansion

00 FC0016 −00 FFFF16 1K On-chip Module Registers1

01 000016 −0F FFFF16 960K Expansion Memory

10 000016 −1F FFFF16 1024K Expansion Memory

1.0 Introduction (Continued)

Revision 1.07 35 www.national.com

PC87591E/S/L

Eitherbyte-wideorword-widetransactionstoanyaddress withinthe memory address space may be used to access memory

devices.

Only byte-wide transactions may be used to access byte-wide registers, and only word-wide transactions may be used to

access word-wide registers. Attempts to read a write-only register or write to a read-only register cause unpredictable re-

sults.

Zeros must be written to reserved bits unless stated otherwise. Reading reserved bits returns an undefined value. When

modifying a register with reserved bits, the data read from reserved a bit can be written back to it.

Accessing Base Memory

In the PC87591E and PC87591S the Base memory is the main storage for code and data. When Shared BIOS is enabled,

the Base memory may also be used for storing BIOS code and data. Figure 6 on page 35 illustrates how on-chip and off-

chip Base Memory are mapped to the PC87591E and PC87591S address space.

The Base Memory is divided into two zones:

●Fast Zone - for addresses with Base Memory in the range of 00 0000 to 01 FFFF. The access time to this zone is

controlled by the BIU Zone 1 conﬁguration registers.

●Slow Zone - for addresses with Base Memory in the range of 02 0000 to 0F FFFF. The access time to this zone is

controlled by the BIU Zone 2 conﬁguration registers.

In the PC87591L, the base memory is used for storing code and data required for basic boot operations. The rest of the code

and data are stored in the Expansion Memory shared by the core firmware and host BIOS. Figure 7 on page 36 illustrates

how on-chip and off-chip Base Memory are mapped to the PC87591L address space.

IRE and OBD Environments - On-Chip Base Memory. In IRE and OBD environments, the on-chip flash (ROM) is used as

Base memory. Note that the size of the available memory may differ among members of PC87591x family (see Tables 1 to

3). The access time to it is controlled by BIU Zones 1 and 2. To allow cycle-by-cycle compatibility with DEV environment,

both zones should be programed in the same way for all environments. Thus to maximize on-chip flash (ROM) performance,

configure BIU Zones 1 and 2, as described in Section 4.1.11 on page 86 and Section 4.16 on page 218, with minimal access

time supported at the frequency in use, as defined in “Flash Read, Write and Erase Time” on page 222.

Off-Chip Base Memory. In DEV environment (when on-chip flash is disabled), the code and constant data are stored in off-

chip Base Memory. In the PC87591E and PC87591S, this off-chip Base Memory has 1016 Kbytes of address space

(00 000016 to 00 DFFF16 and 01 000016 to 0F FFFF16). In the PC87591L, the size of the off-chip Base Memory is 4 Kbytes.

To ensure that the code fits into the on-chip flash in IRE and OBD environments later on, both the code and constant data

should fit within the defined flash size, for the selected member of the PC87591x family.

56 K

64 K

Off-Chip Base Memory

On-Chip Base Memory

Figure 6. Base Memory Address Mapping - PC87591E and PC87591S

56 K

128K

Core Address Map 00 0000

02 0000

Zone 2

Access Time

01 FFFF

0F FFFF

Control

Zone 1

Access Time

Control

2 M

1 M

PC87591S

Flash Size

PC87591E

Flash Size

1.0 Introduction (Continued)

www.national.com 36 Revision1.07

PC87591E/S/L

Accessing Expansion Memory

Expansion Memory Configuration is available in PC87591x versions packed in 176-pin packages. Access to it is enabled

only after:

●The pins used for the memory interface are conﬁgured to operate as Expansion Memory interface signals (see

Section 2.4 on page 54 for details on the alternate functions conﬁguration).

●The BIU Zone 0 Conﬁguration register (SZCFG0), which controls the memory access parameters (e.g., bus width and

access time), is set to support the conﬁguration in use.

The interface signals to the Expansion Memory are:

●8-bit ﬂash or SRAM: SEL0, RD, WR0, D0-7 and A0-19 (fewer address lines may be used with a smaller ﬂash).

●16-bit ﬂash or SRAM: SEL0, RD, WR0-1, D0-15 and A1-19 (fewer address lines may be used with a smaller ﬂash).

Figure 8 shows the External Memory Address Range mapping to the core, in the PC87591E and PC87591S devices.

Figure 9 shows the External Memory Address Range mapping to the core in the PC87591L device. Note that in PC87591L

devices, the External Memory is aliased to low addresses of the core address space, enabling access to memory locations

in the flash from both an address in the low memory and an address in the upper part of the memory.

4 K

64 K

Off-Chip Base Memory

On-Chip Base Memory

Figure 7. Base Memory Address Mapping - PC87591L

4 K

Core Address Map 00 0000

00 0FFF

Zone 1

Access Time

Control

PC87591L

Flash Size

2 M

1 M

1.0 Introduction (Continued)

Revision 1.07 37 www.national.com

PC87591E/S/L

External Memory Mapping into Shared BIOS Memory

When the shared BIOS memory is enabled using the SHBM strap input (SHBM=1) or the Shared Memory Configuration

Registers (LDN=10h), the Expansion Memory address range is mapped into the address range of the host. The PC87591x

uses the wrap-around effect of the core address space (on a 2 Mbyte boundary) using “growing down” addresses, which

enables the host to view the Expansion flash as a continuation of the BIOS Memory. See Section 5.3.2 on page 297 for de-

tails of the memory mapping scheme.

Accessing I/O Expansion Space

The I/O expansion protocol enables implementing I/O devices or GPIO ports in the system, in addition to those available on-

chip, for IRD, OBD and DEV environments. In addition, in DEV environment, some of the on-chip I/O port pins are used to

interface with off-chip peripherals. In such a case, the I/O expansion protocol is used to implement the functionality of these

I/O ports, using off-chip external logic. Access to these ports is through the same addresses used for the ports’ on-chip im-

plementation.

56 K

64 K

128 K

2 M

1 M

Core Address Map Expansion Memory Address

Figure 8. Expansion Memory (Zone 0) Address Range - PC87591E and PC87591S

1 M

64 K

2 M

1 M

Core Address Map Expansion Memory Address

Figure 9. Expansion Memory (Zone 0) Address Range - PC87591L

1 M

1.0 Introduction (Continued)

www.national.com 38 Revision1.07

PC87591E/S/L

The I/O expansion space is mapped to the address space 00 FB0016 to 00 FBFF16. This space is partitioned as follows:

●Addresses in the range 00 FB0016 to 00 FB2216 are used by GPIO ports PH, PI, PJ, PK, PL and PM (either on-chip

or in their off-chip implementation, while the chip is in DEV environment).

●Address 00 FBFE16 is used only in DEV environment by the MCFGSH register and must be written after each write

to the MCFG with the same data written to the MCFG.

●Addresses in the range 00 FBC016 to 00 FBFF16 are reserved for development board use.

●All other addresses may be used by the application for adding additional I/O elements.

The PC87591x accesses the off-chip I/O expansion using the I/O zone of the BIU. The zone select signal (SELIO), address

lines A0-7 and the RD and WR0 signals are used to interface to the off-chip logic.

1.5.2 Host Address Domain Memory Map

The host address space includes memory space and I/O space.

The I/O space used by the PC87591x is configured through the PC87591x configuration registers. The configuration register

address is defined by strap inputs (BADDR0-1) to be one of two fixed addresses or an address defined by the core using

registers in the MSWC module.

When a Shared BIOS scheme is enabled via the SHBM strap input, the PC87591x is mapped to enable the host to boot from

a shared flash device. The PC87591x supports either memory or FWH transactions for the host memory interface, with au-

tomatic selection between them (see Section 6.1.11 on page 349). Section 5.3 on page 297 discusses the mapping of mem-

ory between the host and core domains and the read and write access protection scheme from the host and core sides.

Following the boot process, the Shared Memory configuration registers (see Section 6.1.11 on page 349) enable setting

memory sharing. The configuration setting includes defining the memory protocol in use (memory or FWH) and the address

range used in the host address space. The configuration registers allow the defaults set by the SHBM strap input to be over-

ridden; this enables using the shared memory for purposes other than system BIOS (e.g., PC87591x firmware update and

secured storage of information).

1.5.3 Core Access to Host Controlled Peripherals

The core may access host domain devices through the Core to Host Controlled Functions access bridge. The bridge em-

ploys an indirect mapping scheme.

There is only a single set of peripheral registers for host and core use. The bus arbitration guarantees that only one of the

two register accesses occurs at any given time, but this does not prevent problems that may be caused by conflicting write

transactions. When such a case is expected, the core lock mechanism may be used to protect access to one or more of the

devices. The lock may also be used to protect from the host from access to devices due to the security reasons.

The core accesses a register by specifying the logical device and the offset of the register within the logical device. Note that

the configuration registers’ index and data registers are also handled as a logical device. The core triggers a read by writing

1 to the read start bit and waits for the bit to clear; it can then read the data from the data register. The core triggers a write

by performing a write operation to the data register.

Section 5.4 on page 313 provides details of the bridge and its operation.

Revision 1.07 39 www.national.com

PC87591E/S/L

2.0 Signal/Pin Description and Conﬁguration

2.1 CONNECTION DIAGRAMS

176-pin Low Proﬁle Plastic Quad Flatpack (LQFP)

Order Number PC87591E-VPC / PC87591S-VPC / PC87591L-VPC

NS Package Number VPC176

5 101520253035

95100105110

115120

125

130

135

140

145

150

155

160

165

170

175

IOPE1/AD5

IOPE0/AD4

AD3

AD2

AD1

AD0

KBSIN7

KBSIN6

KBSIN5

KBSIN4

KBSIN3

KBSOUT15

KBSOUT14

KBSOUT13

KBSOUT12

IOPJ7/BRKL_RSTO

IOPJ6/PLI

IOPJ5/PFS

IOPJ4/BST2

IOPJ3/BST1

IOPJ2/BST0

GND

VCC

IOPK3/A11

IOPK2/A10

VCC

GND

IOPI0/D0

IOPI1/D1

IOPI2/D2

IOPI3/D3

IOPK1/A9

IOPK0/A8

IOPI4/D4

IOPI5/D5

IOPI6/D6

IOPI7/D7

IOPM0/D8

IOPM1/D9

IOPJ1/WR0

IOPJ0/RD

IOPM2/D10

IOPM3/D11

32KX1/32KCLKIN

GND

32KX2

VBAT

IOPB0/URXD

IOPB1/UTXD

IOPB2/USCLK

IOPB3/SCL1

IOPB4/SDA1

VCC

GND

CLK

IOPC1/SCL2

IOPC2/SDA2

VCC

IOPB7/RING/PFAIL/RESET2

IOPH1/A1/ENV1

IOPH2/A2/BADDR0

IOPH3/A3/BADDR1

IOPH4/A4/TRIS

IOPH5/A5/SHBM

IOPH6/A6

IOPH7/A7

IOPK4/A12

IOPK5/A13_BE0

VCC

GND

IOPF7/PSDAT4

IOPF6/PSCLK4

IOPK6/A14_BE1

IOPK7/A15_CBRD

IOPF5/PSDAT3

IOPF4/PSCLK3

IOPF3/PSDAT2

IOPF2/PSCLK2

IOPL0/A16

IOPL1/A17

IOPF1/PSDAT1

IOPF0/PSCLK1

TMS

TDO

TINT

TCK

IOPL2/A18

IOPL3/A19

DA3

DA2

DA1

DA0

AGND

AVCC

DN/AD9

DP/AD8

IOPE3/AD7

IOPE2/AD6

SEL0

SEL1

IOPL4/WR1

IOPC0

IOPC3/TA1

IOPC5/TA2

IOPC4/TB1/EXWINT22

IOPD6

IOPD7

IOPC6/TB2/EXWINT23

SELIO

IOPH0/A0/ENV0

KBSIN2

TDI

KBSOUT0

KBSOUT1

KBSOUT2

KBSOUT3

KBSOUT4

KBSOUT5

KBSOUT6

KBSOUT7

KBSOUT8

KBSOUT9

KBSOUT10

KBSOUT11

KBSIN0

KBSIN1

PC87591x

176-pin LQFP

(Top View)

IOPM4/D12

IOPM5/D13

IOPM6/D14

IOPE4/SWIN

IOPE6/LPCPD/EXWINT45

LCLK

RESET1

SERIRQ

LDRQ

LFRAME

VDD

GND

LAD3

LAD2

LAD1

LAD0

SMI

PWUREQ

IOPB6/KBRST

IOPD4

IOPD5

VCC

GND

IOPC7/CLKOUT

IOPM7/D15

IOPE7/CLKRUN/EXWINT46

IOPD0/RI1/EXWINT20

IOPE5/EXWINT40

IOPD1/RI2/EXWINT21

IOPD2/EXWINT24/RESET2

IOPD3/ECSCI

IOPA0/PWM0

IOPA1/PWM1

IOPA2/PWM2

IOPA6/PWM6

IOPA3/PWM3

IOPA5/PWM5

IOPA4/PWM4

IOPA7/PWM7

IOPB5/(GA20)

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 40 Revision1.07

PC87591E/S/L

128-pin LQFP Package

Order Number: PC87591E-VLB / PC87591S-VLB

NS Package Number VLB128

IOPE4/SWIN

IOPE6/LPCPD/EXWINT45

LCLK

RESET1

SERIRQ

LDRQ

LFRAME

VDD

GND

LAD3

LAD2

LAD1

LAD0

SMI

PWUREQ

IOPB6/KBRST

IOPB5/(GA20)

IOPC7/CLKOUT

IOPE7/CLKRUN/EXWINT46

IOPD0/RI1/EXWINT20

GND

VCC

IOPE1/AD5

IOPE0/AD4

AD3

AD2

AD1

AD0

IOPH1/A1/ENV1

IOPH2/A2/BADDR0

IOPH3/A3/BADDR1

IOPH4/A4/TRIS

IOPH5/A5/SHBM

IOPH6/A6

VCC

GND

IOPF7/PSDAT4

IOPF6/PSCLK4

IOPF5/PSDAT3

IOPF4/PSCLK3

IOPF3/PSDAT2

IOPF2/PSCLK2

IOPF1/PSDAT1

IOPF0/PSCLK1

TMS

TDO

TINT

TCK

DA3

DA2

DA1

DA0

AGND

AVCC

DN/AD9

DP/AD8

IOPE3/AD7

IOPE2/AD6

IOPH0/A0/ENV0

TDI PC87591x

128-pin LQFP

(Top View)

110

115

120

125

100

105

VCC

GND

IOPI0/D0

IOPI1/D1

IOPI2/D2

IOPI3/D3

IOPI4/D4

IOPI5/D5

IOPI6/D6

IOPI7/D7

IOPJ1/WR0

IOPJ0/RD

32KX1/32KCLKIN

GND

32KX2

VBAT

IOPB0/URXD

IOPB1/UTXD

IOPB2/USCLK

IOPB3/SCL1

IOPB4/SDA1

IOPC1/SCL2

IOPC2/SDA2

VCC

IOPB7/RING/PFAIL/RESET2

IOPH7/A7

IOPC0

IOPC3/TA1

IOPC5/TA2

IOPC4/TB1/EXWINT22

IOPC6/TB2/EXWINT23

SELIO

IOPE5/EXWINT40

KBSOUT11

KBSOUT0

KBSOUT1

KBSOUT10

KBSOUT9

KBSOUT8

KBSOUT7

KBSOUT6

KBSOUT5

KBSOUT4

KBSOUT3

KBSOUT2

IOPA7/PWM7

IOPA6/PWM6

IOPA5/PWM5

IOPA4/PWM4

IOPA3/PWM3

IOPA2/PWM2

IOPA1/PWM1

IOPA0/PWM0

IOPD3/ECSCI

IOPD2/EXWINT24/RESET2

IOPD1/RI2/EXWINT21

KBSIN0

KBSIN1

KBSIN2

KBSIN3

KBSIN4

KBSIN5

KBSIN6

KBSIN7

KBSOUT15

KBSOUT14

KBSOUT13

KBSOUT12

2.0 Signal/Pin Description and Configuration (Continued)

Revision 1.07 41 www.national.com

PC87591E/S/L

2.2 BUFFER TYPES AND SIGNAL/PIN DIRECTORY

The following sections contain detailed functional descriptions and electrical DC characteristics for the PC87591x signals.

The pin multiplexing and function selection criteria are described in Section 2.4 on page 54. The signal DC characteristics

are denoted by a buffer type symbol described briefly below and in further detail in Section 7.2 on page 374. The pin multi-

plexing information refers to two different types of multiplexing:

●MUX - Multiplexed, denoted by a slash (/) between pins in the diagram in Section 2.1 on page 39. Pins are shared

between two different functions. Each function is associated with different board connectivity. Normally, the function

selection is determined by the board design and can not be changed dynamically. The multiplexing options must be

conﬁgured by the core in order to comply with the board implementation.

●MM - Multiple Mode, denoted by an underscore (_) between pins in the diagram in Section 2.1 on page 39. Pins have

two or more modes of operation within the same function. These modes are associated with the same external

(board) connectivity. Mode selection may be controlled by the device driver through the registers of the functional

block and do not require a special setup. These pins are not considered multiplexed pins from the conﬁguration per-

spective. The mode selection method as well as the signal speciﬁcation in each mode are described in the functional

description.

Table 4. Buffer Types

Symbol Description

INAC Input, analog to ACM

INAD Input, analog to ADC

INCS Input, CMOS compatible, with Schmitt Trigger

INDI Input, analog from remote diode

INOSC Input, from crystal oscillator (not characterized)

INPCI Input, PCI 3.3V

INSM Input, SMBus compatible

INTInput, TTL compatible

INTS Input, TTL compatible, with Schmitt Trigger

INULR Input, power, resistor protected (not characterized)

Op/n Output, push-pull output buffer that is capable of sourcing pmA and sinking

nmA

ODnOutput, open-drain output buffer that is capable of sinking nmA

ODA Output, analog from DAC

ODI Output, analog to remote diode

OOSC Output, to crystal oscillator (not characterized)

OPCI Output, PCI 3.3V

PWR Power pin

GND Ground pin

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 42 Revision1.07

PC87591E/S/L

2.2.1 ACCESS.bus (ACB1 and ACB2) Interface

2.2.2 Analog Interface

2.2.3 Clocks

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

SCL2-1 125,

121 169,

163 I/O INSM/OD2VCC ACCESS.bus Serial Clock 1 and 2 Signals.

An internal pull-up for this pin is optional.

SDA2-1 126,

122 170,

164 I/O INSM/OD2VCC ACCESS.bus Serial Data 1 and 2 Signals.An

internal pull-up for this pin is optional.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

AD9-0 70-61 94-93,

90-87,

84-81

IIN

AD AVCC Analog to Digital Converter Inputs.

DA3-0 76-73 102-99 O ODA AVCC Digital to Analog Converter Outputs.

DP 69 93 O ODI AVCC Diode Anode. Remote diode current source.

Connected to remote discrete diode.

DN 70 94 I INDI AVCC Diode Cathode. Remote diode current sink.

Connected to remote discrete diode. Must be

grounded when not used.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

32KCLKIN 116 158 I INTVPP 32.768 KHz Clock Input.

32KX1 116 158 I INOSC VPP 32.768 KHz Crystal Oscillator Input. Input

from external crystal oscillator circuitry. See

Figure 113 on page 356.

32KX2 118 160 O OOSC VPP 32.768 KHz Crystal Oscillator Output. Output

to external crystal oscillator circuitry. See

Figure 113 on page 356.

CLK N/A 47 O O1/2 VCC Clock Output. PC87591x Core Domain system

clock. Available in all environments, in the

176-pin package option.

CLKOUT 3 1 O O2/4 VCC Clock Output. This pin may output either the

32.768 KHz clock or the Core Domain system

clock (CLK). CLKM bit in MCFG register

selects the output clock frequency.

2.0 Signal/Pin Description and Configuration (Continued)

Revision 1.07 43 www.national.com

PC87591E/S/L

2.2.4 Core Bus Interface Unit (BIU)

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

A3-0 95-92 127-124 O O1/2 VCC Address Bus, bits 0-19. Core external address

bus. Affected or used by any transaction on the

internal core-bus, including DMA transactions

and accesses to the internal memory.

A19-8 N/A 103-104

112-113

120-121

129-130

134-135

142-143

A7-4 99-96 133-131,

128 OO

2/12 VCC

D7-4,

D3-0 109-

102 147-144

141-138 I/O INT/O1/2 VCC Data bus, bits 0-15. Core external data bus.

Used for core access to external memory or I/O

devices. When accessing an 8-bit external

memory or I/O device, only D0-7 should be

used.

D15-14,

D13-12,

D11-10,

D9-8

N/A 149-148

156-155

4-3

28-27

RD 110 150 O O1/2 VCC Read Control. Core external read strobe. Can

be used as output enable for external memory

of I/O devices.

SEL0 N/A 173 O O1/2 VCC Zone Select 0. Chip-select signal for external

memory devices mapped to zone 0.

SEL1 N/A 174 O O1/2 VCC Zone Select 1. Chip-select signal for external

memory devices mapped to zones 1 and 2

(Base Memory). Available in DEV environment

for off-chip emulation of the on-chip ﬂash or

ROM. In IRE and OBD environments, zones 1

and 2 are mapped to the on-chip ﬂash or ROM

and SEL1 output is inactive.

SELIO 112 152 O O1/2 VCC I/O Zone Select. Chip-select signal for external

I/O devices mapped to this zone. Can be used

for mapping off-chip I/O expansion devices to

the core address space.

WR1 N/A 48 O O1/2 VCC Write Control 1 and 0. Indicates writes to bytes

1 and 0, respectively, of the BIU data bus.

WR0 111 151

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 44 Revision1.07

PC87591E/S/L

2.2.5 Development System Support

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

BE1-0 N/A 121,129 O O1/2 VCC Byte Enable bits 1 and 0 on monitor bus

cycles.

BRKL_RSTO N/A 76 I INT/O1/2 VCC Break Line and Reset Out. When the Core

bus is active, the pin is used as a BRKL input.

It Indicates to the core that a breakpoint is

needed once the currently fetched instruction

goes into execution.

When the core bus is not active, the signal is

used as a RSTO output. It indicates to the

system that an internal reset to the core and

its peripherals occurred.

BST2-0 N/A 69,

63-62 OO

1/2 VCC Bus Status bits 2-0 on monitor bus cycles. In

DEV environment, these pins allow monitoring

of the external bus cycles. When OBR bit in

BCFG register is set, the internal bus cycles

are also visible on the external bus. See also

Table 41 on page 273.

CBRD N/A 120 O O1/2 VCC Core Bus Read Status on monitor bus

cycles.

Available in all modes. See Section 4.1.9 on

page 81.

PFS N/A 70 O O1/2 VCC Pipe Flow Status.

PLI N/A 75 O O1/2 VCC Pipe Long Instruction.

TCK 78 106 I INTS VCC JTAG Test Clock.

TDI 80 108 I INTVCC JTAG Test Data In.

TDO 79 107 O O1/2 VCC JTAG Test Data Out.

TINT 77 105 O OD2VCC JTAG Test Interrupt.

TMS 81 109 I INTVCC JTAG Test Mode Select.

2.0 Signal/Pin Description and Configuration (Continued)

Revision 1.07 45 www.national.com

PC87591E/S/L

2.2.6 General-Purpose I/O (GPIO) and Internal Keyboard Scan

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

KBSIN7-0 60-53 80-77,

74-71 IIN

CS/INAC VCC Keyboard Scan Inputs. The input side of the

internal keyboard scan lines. These inputs may

be conﬁgured to work with either Schmitt trigger

inputs, for operation with switch based

keyboards, or with internal analog voltage

comparators to interface to a resistive keyboard

matrix. KBSIN7-0 are referenced to VCC and

are designed to work using a 3.3V supply. See

Section 4.14 on page 208 for more details.

KBSOUT15-0 52-37 68-64,

61-56,

53-49

OOD

6VCC Keyboard Scan Outputs. The output side of

the internal keyboard scan lines.

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 46 Revision1.07

PC87591E/S/L

IOPA7-0 33-26 43,

40-36,

33-32

I/O INTS/O3/6 VCC General-Purpose I/O Ports. The GPIO

registers are accessible by the core for read,

write and conﬁguration. Each of these GPIO

signals can be individually conﬁgured to be

input or output. The pins may be used as GPIO

or assigned to their respective alternate

functions. See Section 2.4 on page 54 for

assignment of GPIO pins to alternate functions.

See Section 4.5 on page 113 for further details

on the GPIO pins and their functionality.

IOPD1-0 23-22 29, 26

IOPB7-3 123,

6-5,

122-121

165,

6-5,

164-163

I/O INTS/O1/2 VCC

IOPC6-1 2-1,

128-125 176-175

172-169

IOPH3-0 95-92 127-124

IOPI7-0 109-102 147-144

141-138

IOPJ7-2 N/A 76-75

70-71

63-62

IOPJ1-0 111-110 151-150

IOPK7-0 N/A 120-121

129-130

134-135

142-143

IOPL4-0 N/A 48,

103-104

112-113

IOPM7-0 N/A 28-27,

4-3,

156-155

149-148

IOPB2-0 120,

114-113 162,

154-153 I/O INTS/O2/4 VCC

IOPC7 3 1

IOPD7-4 N/A 55-54,

42-41 I/O INTS/O2/12 VCC

IOPD3-2 25-24 31-30

IOPF7-0 89-82 119-114

111-110

IOPH7-4 99-96 133-131

128

IOPC0 124 168 O O3/6 VCC General-Purpose Output Port IOPC0. IOPC0

is are targeted for use as power supply control

for the power supply unit. It is accessible by the

core for write and conﬁguration. On VCC Power-

Up reset, the default state TRI-STATE; it is not

affected by other types of reset. See Section 4.5

on page 113 for further details on these GPIO

pins and their functionality.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

2.0 Signal/Pin Description and Configuration (Continued)

Revision 1.07 47 www.national.com

PC87591E/S/L

IOPE7-0 21-20,

34,

68-65

25-24,

44,

90-87

IIN

TS VCC General-Purpose Input Port. These pins serve

as input-only pins. The GPIO registers are

accessible by the core for read and

conﬁguration. The pins may be used as GPIO

or assigned to their respective alternate

functions. IOPE0-3 and IOPE5 do not have an

internal pull-up resistor option. Note that

IOPE0-3 and IOPE6-7 are not 5V tolerant. See

Section 2.4 on page 54 for GPIO pin

assignment to alternate functions. See

Section 4.5 on page 113 for further details on

the GPIO pins and their functionality.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 48 Revision1.07

PC87591E/S/L

2.2.7 Host Interface

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

CLKRUN 21 25 I/O INPCI/OD6VDD Clock Run. Same as PCI CLKRUN. When

high, indicates that the LPC clock will be slowed

down or stopped. In this case, the PC87591x

may pull it down to request full speed of the

clock.

GA20 5 5 O O1/2 VCC Gate A20. Implemented using IOPB5 port

output. See Section 5.5.4 on page 322 for

signal operation and behavior when VDD is

down.

KBRST 6 6 O O1/2 VCC Keyboard Reset Output. See Section 5.5.4

on page 322 for signal operation and behavior

when VDD is down.

LAD0-3 10-13 15-13,

10 I/O INPCI/OPCI VDD LPC Address-Data. Multiplexed command,

address bidirectional data and cycle status.

LCLK 16 18 I INPCI VDD LPC Clock. Practically the PCI clock (up to 33

MHz).

ECSCI 25 31 O O2/12 VCC EC SCI. Generates an Embedded Controller

SCI interrupt to the chipset. This signal is

typically connected to one of the chipset GPI

inputs.

LDRQ 8 8 O OPCI VDD LPC DMA Request. Encoded Bus Master

request for LPC I/F.

LFRAME 9 9 I INPCI VDD LPC Frame. Low pulse indicates the beginning

of a new LPC cycle or the termination of a

broken cycle.

LPCPD 20 24 I INPCI VCC Power Down. Indicates that power will be shut

off on the LPC interface.

RESET1 17 19 I INPCI VCC Reset 1. A falling edge on this signal starts a

reset sequence of the PC87591x. For details,

see details in Section 3.2 on page 65.

RESET2 24/123 30/165 I INCS VDD Reset 2. A level low reset to the LPC interface

and Host Controlled Functions conﬁguration

registers and Shared Memory host registers.

For details, see Section 3.2 on page 65.

RESET2 is either assigned to one of two

optional pins or it is disabled, as deﬁned in the

protection words stored in the ﬂash memory.

See Section 2.4.1 on page 54 and

Section 4.16.6 on page 226 for the

conﬁguration of this signal.

PWUREQ 19 23 O O1/2 VCC Power-Up Request.

SERIRQ 7 7 I/O INPCI/OPCI VDD Serial IRQ. The interrupt requests are

serialized over a single pin, where each IRQ

level is delivered during a designated time slot.

SMI 18 22 I/O INTS/OD12 VCC System Management Interrupt.

2.0 Signal/Pin Description and Configuration (Continued)

Revision 1.07 49 www.national.com

PC87591E/S/L

2.2.8 Interrupt and Wake-Up Inputs (ICU and MIWU)

2.2.9 Power and Ground

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

EXWINT20

EXWINT21

EXWINT22

EXWINT23

EXWINT24

EXWINT40

EXWINT45

EXWINT46

128

172

176

IIN

TS VCC External Wake-up/Interrupt Inputs. Fed into

the Multi-Input Wake-up Unit (MIWU) for wake-

up or interrupt. Can be used as external

source for wake-up or interrupt. For details on

interrupt and wake-up event assignment, see

Table 17 on page 105.

PFAIL 123 165 I INCS VCC Power Fail. Non-maskable external interrupt

source. This assigned interrupt is non-

maskable only after being enabled by software

after reset.

SWIN 4 2 I INCS VCC Power Switch Input. Indicates a user request

to turn the power on or off. This signal is

connected to the Multi-Input Wake-up Unit

(MIWU) for wake-up of the core domain and

interrupt generation to the core for handling.

For details on interrupt and wake-up event

assignment, see Table 17 on page 105.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

AGND 72 96 I GND Analog Ground. Used as ground for the Analog

to Digital Converter (ADC) and the Digital to

Analog Converter (DAC).

AVCC 71 95 I PWR Analog 3.3V Power supply. Used as power

supply for the Analog to Digital Converter (ADC)

and the Digital to Analog Converter (DAC).

GND 15, 36,

90,

101,

117

17, 35,

46,122,

137,

159,167

I GND Ground. Serves for both on-chip logic, output

drivers and back-up battery circuit. See “Power

Connection and Layout Guidelines” on page 63

for details on connections with AGND.

VBAT 119 161 I INULR Battery Power Supply. Provides battery backup

to the Mobile System Wake-Up Control registers,

to the RTC and to the 32 KHz crystal oscillator

when VCC is lost. The pin is connected to the

internal logic through a series resistor for UL

protection.

VCC 35,

91,100,

115

34, 45,

123,136,

157,166

I PWR Standby Digital 3.3V Power Supply. Used for

all core-domain digital logic and all associated

I/O pins.

VDD 14 16 I PWR Digital 3.3V Power Supply. Serves as power

supply for the LPC interface and some of the

host-controlled functions.

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 50 Revision1.07

PC87591E/S/L

2.2.10 PS/2 Interface

2.2.11 Strap Configuration

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

PSCLK4-1 88, 86,

84, 82 118,

116,

114,

110

I/O INT/O2/12 VCC PS/2 Channel 1 through 4 Clock signal.

PSDAT4-1 89, 87,

85, 83 119,

117,

115,

111

I/O INT/O2/12 VCC PS/2 Channel 1 through 4 Data signal.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

BADDR1-0 95-94 127-126 I INCS VCC I/O Base Address. Sampled at VCC Power-Up

reset to determine the base address of the

conﬁguration Index-Data register pair as follows:

No pull-up resistor: 2E16-2F16

10 KΩexternal pull-up

resistor on BADDR0:4E16-4F16

10 KΩexternal pull-up

resistor on BADDR1:Core deﬁned

ENV1-0 93-92 125-124 I INCS VCC Environment Select 1 and 0. Sampled at VCC

Power-Up reset to determine the device

operation environment, either IRE, OBD or DEV.

Each pin is pulled to 0 (set environment to IRE =

00) by an internal resistor or set to 1 by an

external 10 KΩpull-up resistor.

For further details refer to Section 2.3 on

page 53.

SHBM 97 131 I INCS VCC Shared Host BIOS Memory. Sampled at VCC

Power-Up reset to determine the state of the

shared Host BIOS memory. Pulled to 0 (disables

the shared host BIOS memory) by an internal

resistor or set to 1 by an external 10 KΩpull-up

resistor to enable the shared BIOS mode.

TRIS 96 128 I INCS VCC TRI-STATE. Forces the device to ﬂoat all its

output and I/O pins (except for DAC outputs and

32KX2) if an external pull-up resistor is

connected. Sampled at VCC Power-Up reset.

2.0 Signal/Pin Description and Configuration (Continued)

Revision 1.07 51 www.national.com

PC87591E/S/L

2.2.12 Mobile System Wake-Up Control (MSWC)

2.2.13 Timers and PWM

2.2.14 Universal Synchronous/Asynchronous Receiver/Transmitter (USART)

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

RING 123 165 I INCS VCC Telephone Line Ring. Detection of a pulse

train on this pin is a wake-up event that can

activate the power-up request (PWUREQ). The

pin has a Schmitt Trigger input buffer, powered

by VCC.

RI1 22 26 I INTS VCC Ring Indicator. When low, indicates that a

telephone ring signal has been received by the

modem. Ring signals are monitored during

power-off for wake-up event detection.

RI2 23 29

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

TA2 1 175 I/O INT, O1/2 VCC Timer Pin A for Timers 2 and 1.

TA1 127 171

TB2 2 176 I INTVCC Timer Pin B for Timers 2 and 1.

TB1 128 172

PWM7-0 33-26 43,

40-36,

32-33

3/6 VCC PWM Output 7-0.

Signal 128-Pin

LQFP 176-Pin

LQFP I/O Buffer

Type Power

Well Description

UTXD 114 154 O O2/4 VCC USART Transmit Data.

URXD 113 153 I INTVCC USART Receive Data.

USCLK 120 162 I/O INCS/O2/4 VCC USART Serial Clock. May be used as input or

output when the USART is conﬁgured to

operate in its synchronous mode of operation.

2.0 Signal/Pin Description and Configuration (Continued)

www.national.com 52 Revision1.07

PC87591E/S/L

2.2.15 Internal Pull-Up and Pull-Down Resistors

The signals listed in Table 5 can optionally support internal pull-up (PU) and/or pull-down (PD) resistors. See Section 7.3 on

page 377 for the values of each resistor type.

Table 5. Internal Pull-Up and Pull-Down Resistors

Signal 128-Pin

LQFP 176-Pin

LQFP Type Comments

ACCESS.bus (ACB)

SCL2-1 125,

121 169,

163 PU80 Programmable

SDA2-1 126,

122 170,

164 PU80 Programmable

General-Purpose I/O (GPIO) Ports

IOPA7-0 33-26 43, 40-36,

33-32 PU80 Programmable

IOPB7-0 123, 6-5,

122,121,120,

114-113

165, 6-5,

164-163,

120,114-113

PU80 Programmable

IOPC7-0 3-1,128-125 3,176-175,

172-169 PU80 Programmable

IOPD7-4 N/A 55-54, 42-

41 PU80 Programmable

IOPD3-0 25-21 31-30, 29,

IOPE7,6,4 21-20, 4 25-24, 2 PU80 Programmable

IOPF7-0 89-82 119-114,

111-110 PU80 Programmable

Internal Keyboard Scan (KBC)

KBSIN7-0 60-53 80-77, 74-

71 PU80 Programmable

PS/2 Interface

PSCLK4-1 88, 86,

84, 82 118,116,

114,110 PU80 Programmable

PSDAT4-1 89, 87,

85, 83 119,117,

115,111 PU80 Programmable

Strap Conﬁguration

BADDR1-0 95-94 127-126 PD80 Strap1

1. Active only during VCC Power-Up reset.

ENV1-0 93-92 125-124 PD80 Strap1

TRIS 96 128 PD80 Strap1

SHBM 97 131 PD80 Strap1

2.0 Signal/Pin Description and Configuration (Continued)

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PC87591E/S/L

2.3 STRAP PINS

During VCC Power-Up reset, the ENV(0-1), TRIS, SHBM and BADDR strap input signals are sampled. Internal pull-down

resistors set these signals to 0. These resistors are active only during VCC Power-Up reset. An external 10 KΩresistor con-

nected to VCC may be used to set them to 1.

Setting the Environment

ENV0 and ENV1 determine the operating environment. Table 6 shows the settings allowed. Pulling both ENV0 and ENV1

to 1 produces unpredictable results. In IRE and OBD environments, the TRIS strap input may be used for floating all the

device signals. In other cases it should be kept low.

Figures 1 on page 24, 3 on page 31 and 4 on page 32 demonstrate how to use the ENV0-1 signals to configure the

PC87591x for IRE, OBD and DEV environments, respectively.

Other Strap Pin Settings

Table 7 provides brief descriptions of other strap inputs. For details on SHBM and TRIS, see Section 5.3 on page 297 and

Section 4.20.4 on page 272, respectively.

System Load on Strap Pins

The loads on the strap pins should not cause the voltage on them to drop below VIH when the pins should be high (1), or to

rise above VIL when they should be low (0). See Section 7.3.2 on page 377.

If the load caused by the system on the strap pins exceeds 10 µA, use either an external pull-down resistor to keep the pin

at 0 or a pull-up resistor with lower resistance to keep the pin at 1.

To reduce power consumption, in Idle mode, pins with strap inputs on them and a signal function other than GPIO are put

in TRI-STATE or drive the strap-pin value. For pins with strap inputs that function as GPIO, it is recommended that the ap-

plication drive the strap value as output to the value defined by the strap pin. For pins with strap and address line function-

ality, when the address configuration is enabled, the signal is driven by the hardware to its strap value on reset.

Table 6. Environment Pin Settings

Environment ENV0 ENV1 TRIS

IRE 0 0 01

1. When set to 1, the PC87591x is put in TRI-STATE

mode.

OBD 0 1 01

DEV 1 0 0

PROG 1 1 0

Table 7. Other Strap Pin Settings

Strap Pin Internal Pull-Down (0) External Pull-Up (1)

BADDR1-0 SuperI/O Conﬁguration Base Address see Table 47 on page 335

SHBM Disables shared memory with host BIOS Enables shared memory with host BIOS

TRIS Normal operation While in IRE and OBD environments, causes PC87591x to

ﬂoat its output and I/O signals for system test purposes

and clip-on ISE use

2.0 Signal/Pin Description and Configuration (Continued)

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PC87591E/S/L

Strap Pin Status Register (STRPST)

The STRPST register is a byte-wide, read-only register. It enables the software to read the value set to strap pins during

Power-Up reset. STRPST bits provide the value of their respective strap input. See Table 7 for bit details.

Location: 00 FF1216

Type: RO

Reset Value: According to external straps

2.4 ALTERNATE FUNCTIONS

2.4.1 GPIO with Alternate Functions

The PC87591x uses the GPIO port pins to multiplex functions, thereby maximizing the device’s flexibility. Table 8 lists all the

pins with such alternate functions and summarizes their selection criteria. To select alternate pin functions, strap inputs flash

memory and configuration registers are used as follows:

●The ports’ Alternate Function Control register controls the IOPA, IOPB, IOPC, IOPD, IOPE and IOPF pins. Each of

the ports’ pins may be used as a GPIO port or its alternate function, based on the setting of the corresponding bit in

PxALT register.

●The environment setting and MCFG bits control port IOPH, IOPI, IOPJ, IOPK, IOPL and IOPM pins. In IRE and OBD

environments, these pins may function either as GPIO or their alternate function (as indicated in the table). In DEV

environment, they all function as their alternate functions.

●Interrupts may be enabled together with the use of the pin as input or with its alternate function when the alternate

function is an input. Enabling the interrupt input is done via the port’s alternate function or the respective bit in EICFG

●Strap inputs and their associated internal pull-down resistor function during VCC Power-Up reset.

●The Protection Word in the ﬂash conﬁgures the use of RESET2 input.

When a pin is used as GPIO and not as its alternate function, disable the alternate function in the relevant module’s register.

Note: In Table 8, the PKG column shows pins available in both 128- and 176-pin packages and pins available only in 176-

pin packages.

Bit 76543210

Name Reserved BADDR1 BADDR0 SHBM

Reset

Table 8. Alternate Function Selection

PKG GPIO Alternate Function 1 Alternate Function 2

128/176 Name Type Module Signal Name Select Module Signal Name Select

128/176 IOPA0 I/O PWM PWM0 PAALT.0

128/176 IOPA1 I/O PWM1 PAALT.1

128/176 IOPA2 I/O PWM2 PAALT.2

128/176 IOPA3 I/O PWM3 PAALT.3

128/176 IOPA4 I/O PWM4 PAALT.4

128/176 IOPA5 I/O PWM5 PAALT.5

128/176 IOPA6 I/O PWM6 PAALT.6

128/176 IOPA7 I/O PWM7 PAALT.7

128/176 IOPB0 I/O USART URXD PBALT.0

128/176 IOPB1 I/O UTXD PBALT.1

128/176 IOPB2 I/O USCLK PBALT.2

128/176 IOPB3 I/O ACCESS.bus SCL1 PBALT.3

128/176 IOPB4 I/O SDA1 PBALT.4

2.0 Signal/Pin Description and Configuration (Continued)

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128/176 IOPB5 I/O GA20 and

KBRST (GA20) PBALT.5=01

128/176 IOPB6 I/O KBRST PBALT.6

128/176 IOPB7 I/O MSWC RING PBALT.7 ICU PFAIL/

RESET22PBALT.7/

REST2EN=01

128/176 IOPC1 I/O ACCESS.bus SCL2 PCALT.1

128/176 IOPC2 I/O SDA2 PCALT.2

128/176 IOPC3 I/O Timers TA1 PCALT.3

128/176 IOPC4 I/O TB1 PCALT.4 MIWU EXWINT22 PCALT.4

128/176 IOPC5 I/O TA2 PCALT.5

128/176 IOPC6 I/O TB2 PCALT.6 MIWU EXWNT23 PCALT.6

128/176 IOPC7 I/O Clocks CLKOUT PCALT.7 &

MCFG.CLKOM

128/176 IOPD0 I/O MSWC RI1 PDALT.0 MIWU EXWINT20 PDALT.0

128/176 IOPD1 I/O RI2 PDALT.1 EXWINT21 PDALT.1

128/176 IOPD2 I/O RESET2 RST2EN=10 EXWINT24 PDALT.2

128/176 IOPD3 I/O Host I/F ECSCI PDALT.3

128/176 IOPE0 I ADC Voltage AD4 PEALT.0

128/176 IOPE1 I AD5 PEALT.1

128/176 IOPE2 I AD6 PEALT.2

128/176 IOPE3 I AD7 PEALT.3

128/176 IOPE4 I MIWU SWIN PEALT.4

128/176 IOPE5 I MIWU EXWINT40 PEALT.5

128/176 IOPE6 I LPC Interface LPCPD PEALT.6 EXWINT45 EICFG.

EXWINT45

128/176 IOPE7 I CLKRUN PEALT.7 EXWINT46 EICFG.

EXWINT46

128/176 IOPF0 I/O PS2 Interface PSCLK1 PFALT.0

128/176 IOPF1 I/O PSDAT1 PFALT.1

128/176 IOPF2 I/O PSCLK2 PFALT.2

128/176 IOPF3 I/O PSDAT2 PFALT.3

128/176 IOPF4 I/O PSCLK3 PFALT.4

128/176 IOPF5 I/O PSDAT3 PFALT.5

128/176 IOPF6 I/O PSCLK4 PFALT.6

128/176 IOPF7 I/O PSDAT4 PFALT.7

Table 8. Alternate Function Selection (Continued)

PKG GPIO Alternate Function 1 Alternate Function 2

128/176 Name Type Module Signal Name Select Module Signal Name Select

2.0 Signal/Pin Description and Configuration (Continued)

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128/176 IOPH0 I/O Core BIU A0 DEV Env or

MCFG.

ENEIO=1

or MCFG.

ENEMEM=1

Straps ENV0 Power-up

128/176 IOPH1 I/O A1 ENV1

128/176 IOPH2 I/O A2 BADDR0

128/176 IOPH3 I/O A3 BADDR1

128/176 IOPH4 I/O A4 TRIS

128/176 IOPH5 I/O A5 SHBM

128/176 IOPH6 I/O A6

128/176 IOPH7 I/O A7

128/176 IOPI0 I/O D0

128/176 IOPI1 I/O D1

128/176 IOPI2 I/O D2

128/176 IOPI3 I/O D3

128/176 IOPI4 I/O D4

128/176 IOPI5 I/O D5

128/176 IOPI6 I/O D6

128/176 IOPI7 I/O D7

128/176 IOPJ0 I/O RD

128/176 IOPJ1 I/O WR0

176 IOPJ2 I/O Development

System

Observability

BST0 DEV Env.

176 IOPJ3 I/O BST1

176 IOPJ4 I/O BST2

176 IOPJ5 I/O PFS

176 IOPJ6 I/O PLI

176 IOPJ7 I/O BRKL_RSTO

Table 8. Alternate Function Selection (Continued)

PKG GPIO Alternate Function 1 Alternate Function 2

128/176 Name Type Module Signal Name Select Module Signal Name Select

2.0 Signal/Pin Description and Configuration (Continued)

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PC87591E/S/L

176 IOPK0 I/O Core BIU A8 DEV Env. or

MCFG.

ENEMEM=1

176 IOPK1 I/O A9

176 IOPK2 I/O A10

176 IOPK3 I/O A11

176 IOPK4 I/O A12

176 IOPK5 I/O A13_BE0

176 IOPK6 I/O A14_BE1

176 IOPK7 I/O A15_CBRD

176 IOPL0 I/O A16

176 IOPL1 I/O A17

176 IOPL2 I/O A18

176 IOPL3 I/O A19

176 IOPL4 I/O WR1 DEV Env. or

(MCFG.

ENEMEM=1

and MCFG.

EXMEM16=1)

176 IOPM0 I/O D8

176 IOPM1 I/O D9

176 IOPM2 I/O D10

176 IOPM3 I/O D11

176 IOPM4 I/O D12

176 IOPM5 I/O D13

176 IOPM6 I/O D14

176 IOPM7 I/O D15

128/176 ADC Voltage AD9 ADCCNF. REM-

DEN=0 ADC Temp DN ADCCNF.

REMDEN=1

128/176 AD8 DP

1. GA20 is implemented using the GPIO.

2. RESET2 use is orthogonal to the other alternate functions and is determined by the setting in the on-chip ﬂash

Protection Word (see Section 4.16.6 on page 226), although it is recommended to use it in conjunction with an

interrupt on the same pin. See “Using RESET2 Input” on page 67.

Table 8. Alternate Function Selection (Continued)

PKG GPIO Alternate Function 1 Alternate Function 2

128/176 Name Type Module Signal Name Select Module Signal Name Select

2.0 Signal/Pin Description and Configuration (Continued)

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PC87591E/S/L

2.4.2 System Configuration Registers

For a summary of the abbreviations used for Register Type, see Section 2 on page 34.

Module Conﬁguration Register (MCFG)

The MCFG register is a read/write, byte-wide register. It is used for global system configuration and setup.

Write operations to the MCFG register should write zeros to all reserved bits. On reset, non-reserved bits of MCFG are

cleared to 0. MCFG can be written in Active mode only. Its contents is preserved in Idle mode.

In IRE and OBD environments, all MCFG fields should be used to designate associated pins as GPIO ports or their alternate

functions. In DEV environment, the pins are always allocated for development system use. The I/O ports functionality can

be implemented using off-chip logic.

To guarantee binary and cycle-by-cycle compatibility among the different environments, define the MCFG fields as required

for IRE and OBD even when in DEV environment, and use the I/O Expansion protocol to build an off-chip implementation

of the I/O ports when they are used by the application.

ADBs or ISE systems use the MCFG Shadow (MCFGSH, write only) register to select the functionality of the signal that

reaches the user’s application.

All write operations to the MCFG must be immediately followed by a write to the MCFG Shadow (MCFGSH) register. This

MCFG is loaded with either 0016 or 8016 on reset. See the description of GTMON for behavior of bit 7 during reset.

Software should load MCFGSH with the MCFG register’s value after reset.

The format of MCFG (and MCFGSH) is as follows:

MCFG Location: 00 FF1016

MCFGSH Location: 00 FBFE16

Type: R/W

Mnemonic Register Name Type

MCFG Module Conﬁguration Register R/W

EICFG External Interrupts Conﬁguration Register R/W

IOEE1 and

IOEE2 Input to Output Echo Enable Register 1 and 2 R/W

Bit 76543210

Name GTMON Reserved CLKOM EXMEM16 ENEMEM ENEIO

Reset See text 0000000

Bit Description

0ENEIO (Enable Expansion I/O). Enables the use of the I/O Expansion protocol for expanding the amount of

GPIO pins available to the application. In IRE and OBD environments, when ENEIO is cleared, the associated

pins are used as GPIO signals. When set, enables the use of BIU I/O Zone (SELIO) for the interface with off-

chip logic. Use the BIU I/O Zone conﬁguration to select the access parameters to the I/O Expansion logic and

its bus width.

1ENEMEM (Enable Expansion Memory). Enables the use of the Expansion memory for expanding the amount

of memory available to the application to more than what is provided on chip. When cleared, the associated pins

are used as GPIO signals. When set, enables the use of BIU Zone 0 (SEL0) and the associated address and

data lines for the interface with ﬂash or SRAM devices. Use BIU Zone 0 conﬁguration to select the access

parameters to the Expansion memory and its width.

Set this bit in the 176-pin package only.

2.0 Signal/Pin Description and Configuration (Continued)

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PC87591E/S/L

External Interrupts Conﬁguration Register (EICFG)

The EICFG register is a read/write, byte-wide register. It enables the use of some of the external interrupts. The EICFG bits

have impact only when the pin is configured to its GPIO function. EICFG is cleared (0016) on reset.

Note that some of the pins that have an external interrupt (not controlled by the EICFG register) have an alternate function

that is an input. When a pin’s alternate function is selected, its interrupt function is also enabled.

The format of EICFG is as follows:

Location: 00 FF0016

Type: R/W

2.4.3 GPIO with Echo Configuration

Some of GPIO pins may be paired to generate an input to output echoing with software masking. The input GPIO are input

ports (Px or Py) with a wake-up function. The output ports are a Px type enhanced with the echo mechanism, as described

in Section 4.5.2 on page 114. The input echoing is enabled only when the respective Echo Enable bit in IOEE1-2 registers

is set. The input port should be configured to enable the interrupt function.

2EXMEM16 (16-bit-Wide Expansion Memory). Enables the use of the 16-bit-wide Expansion memory, when the

ENEMEM is set. The bus width indicated in this register should be the same as the bus width deﬁned in Zone

0 of the BIU (SEL0).

0: The External Memory to be eight bits wide

1: Enables the use of a 16-bit-wide External Memory

4-3 CLKOM (Clock Out Mode). Selects the mode of operation of the CLKOUT signal. This ﬁeld is in effect only

when this signal is set for output.

Bits

4 3 Description

0 0: Reserved (default)

0 1: CLK - a clock at the core frequency is driven out

1 0: 32.768 KHz clock output

1 1: Reserved

6-4 Reserved.

7GTMON (Go-to Target Monitor Set Flag). This bit is set to indicate that the code should jump to the beginning

of the Target Monitor (TMON). The reset routine of the application should check this bit and behave accordingly.

Once cleared, this bit can not be set by software.

Bit 76543210

Name Reserved EXWINT46 EXWINT45

Reset 00000000

Bit Description

0EXWINT45 (Enable EXWINT45).

0: EXWINT45 input is blocked (disabled) while not being read as a GPIO.

1: EXWINT45 input is open; this enables the detection of changes on the input to trigger interrupts.

1EXWINT46 (Enable EXWINT46).

0: EXWINT46 input is blocked (disabled) while not being read as a GPIO.

1: EXWINT46 input is open; this enables the detection of changes on the input to trigger interrupts.

7-2 Reserved.

Bit Description

2.0 Signal/Pin Description and Configuration (Continued)

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Input to Output Echo Enable Register 1 and 2 (IOEE1 and IOEE2)

The IOEE1 and IOEE2 registers are read/write, byte-wide registers. They enable the echoing of some of the General-Pur-

pose Input ports, equipped with wake-up, to a specified output. The IOEE bits have an impact only when the output GPIO

is configured to its GPIO function. IOEE1 and IOEE2 are cleared (0016) on reset.

The format of IOEE1 is:

IOEE1 Location: 00 FF0216

Type: R/W

Table 9. GPIO Echo Functions Routing and Echo Enable Bit Assignments

Output Port Echo Enable Bit Input Port

IOPA0 EEPA0 bit in IOEE1 register IOPC4/EXWINT22

IOPA1 EEPA1 bit in IOEE1 register IOPE6/LPCPD/EXWINT45

IOPA2 EEPA2 bit in IOEE1 register IOPE7/CLKRUN/EXWINT46

IOPA3 EEPA3 bit in IOEE1 register IOPF6/PSCLK4

IOPA4 EEPA4 bit in IOEE1 register IOPF7/PSDAT4

IOPC0 EEPC0 bit in IOEE2 register IOPE4/SWIN

IOPB0 EEPB0 bit in IOEE2 register IOPD0/EXWINT20

IOPB1 EEPB1 bit in IOEE2 register IOPD1/EXWINT21

IOPB2 EEPB2 bit in IOEE2 register IOPC6/EXWINT23

IOPD3 EEPD3 bit in IOEE2 register IOPD2/EXWINT24

Bit 76543210

Name Reserved EEPA4 EEPA3 EEPA2 EEPA1 EEPA0

Reset 00000000

Bit Description

0EEPA0.

0: Echo Disabled

1: Echo Enabled

1EEPA1.

0: Echo Disabled

1: Echo Enabled

2EEPA2.

0: Echo Disabled

1: Echo Enabled

3EEPA3.

0: Echo Disabled

1: Echo Enabled

4EEPA4.

0: Echo Disabled

1: Echo Enabled

7-5 Reserved.

2.0 Signal/Pin Description and Configuration (Continued)

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The format of IOEE2 is:

IOEE2 Location: 00 FF0416

Type: R/W

See Table 9 on page 60 for the assignment of the Echo Enable bits to GPIO pairs.

Bit 76543210

Name Reserved EEPC0 EEPD3 EEPB2 EEPB1 EEPB0

Reset 00000000

Bit Description

0EEPB0.

0: Echo Disabled

1: Echo Enabled

1EEPB1.

0: Echo Disabled

1: Echo Enabled

2EEPB2.

0: Echo Disabled

1: Echo Enabled

3EEPD3.

0: Echo Disabled

1: Echo Enabled

4EEPC0.

7-5 Reserved.

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3.0 Power, Reset and Clocks

3.1 POWER

3.1.1 Power Planes

The PC87591x has four power planes (wells), as shown in Table 10.

Table 10. PC87591x Power Planes

For correct PC87591x operation, VCC must be applied whenever VDD is applied. Apply AVCC at the same time that VCC is

applied, protection is provided against rise-time differences only.

3.1.2 Power States

The PC87591x has three main power states:

●Battery Fail

Host Domain, Suspend, Analog and Battery Backed power planes are all powered off (i.e., in this case VDD,V

CC,

AVCC and VBAT are all inactive).

●Power Fail

Host Domain, Suspend and Analog power planes are powered off. Battery Backed power plane is powered on (i.e.,

in this case VDD,V

CC and AVCC are inactive; VBAT is active).

●Power Applied

Suspend, Analog and Battery Backed power planes are powered on, Host Domain power plane may be on or off (i.e.,

in this case VCC,AV

CC are active, VBAT and VDD may be active or inactive).

The Power Applied state has several sub-states, depending on the domain:

—The host domain has Host Power On and Host Power Off states, according to the VDD status;

—The core domain and host-core interface have Active and Idle states. For details, see Section 4.17 on page 235.

The following power states are illegal:

●Host domain on and Suspend and/or Analog off (i.e., VDD active and VCC and/or AVCC are inactive).

●Suspend on and Analog off (i.e., VCC active and AVCC inactive) and vice-versa.

Power Plane Description Power Pins Ground Pins

Host Domain Powers the LPC interface and host controlled

functions (except for RTC and MSWC) and

some external signals1

1. See the tables in Section 2.2.1 on page 42 to Section 2.2.13, speciﬁcally the Power Well

column, for how the PC87591x external interface signals are assigned to various power

planes.

VDD GND

Suspend Powers the core domain, the host-core interface,

the MSWC and their external signals1VCC GND

Analog Powers some internal analog circuits and their

external signals1AVCC AGND

Battery Backed

Powers the RTC, some MSWC registers, the

32.768 KHz clock/crystal oscillator signals and

some other storage elements that should be

preserved at all times1VPP2

2. VPP is an internal power signal derived from VCC or VBAT. VPP is taken from VCC if it is

greater than the minimum value defined; otherwise, VBAT is used as the VPP source. For

more details on the switching between them, refer to Section 6.2.9 on page 360.

GND

3.0 Power, Reset and Clocks (Continued)

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The following table summarizes the power states described in relation with the PC87591x power planes.

Figure 10 shows the power state transitions.

Figure 10. Power State Transitions

3.1.3 Power Connection and Layout Guidelines

The PC87591x requires a power supply voltage of 3.3V ±10% for all the digital supplies (VCC and VDD). The analog power

supply requires a voltage of 3.3V ±10% or 3.3V ±5%. A 3.3V ±5% analog supply is recommended since it improves the

accuracy of measuring input voltage values close to the full-scale (see Section 7.4.1 on page 378).

Table 11. PC87591x Power States and Related Power Planes

Power State Host Domain

(VDD)Suspend

(VCC)Analog

(AVCC)

Battery

Backed

(VPP)VBAT

Battery Fail - - - - -

Power Fail - - - + +

Power Applied

Active and Idle x + + + x

Host Power Off - + + + x

Host Power On + + + + x

Illegal1

1. Operation is not guaranteed.

+--xx

x+-xx

x-+xx

VBAT Off and VCC Off (VPP Off)

Battery Fail

Power Fail

Host

Power Off

Host

Power On

Active

Idle

VBAT On (VPP On)

and VCC Off

VCC On and

VCC On

VCC On and

VDD Off

VDD Off VDD On

Hardware

Event

VCC On and

VDD On

VCC On

VDD On

Power Applied

(VCC On)

VBAT On (VPP On)

and VCC Off

Core DomainHost Domain

Active

with WAIT

Software

Controlled

Hardware

Event

Software

Controlled

VDD Off

3.0 Power, Reset and Clocks (Continued)

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Both AVCC and VCC should be applied for correct operation; and although the PC87591x is protected against damage if op-

erated with only one of them (AVCC or VCC), the ADC and DAC modules do not function correctly in such a case and may

cause current leakage. Therefore, ADC and DAC modules should be left at their reset condition (disabled) or disabled by

firmware until AVCC is within the limits specified above. In addition, the AVCC is internally isolated from VCC to enable AVCC

to be externally filtered or driven by a low-noise power supply.

ThePC87591x is designed to operate with a Lithium backup battery that supplies voltage up to 3.6V. The PC87591x includes

an internal current-limiting resistor on the VBAT input as required to meet UL regulations.

VDD,V

CC and VBAT use a common ground return, named digital ground and marked GND. The analog circuits supplied by

AVCC use a separate ground return, named analog ground and marked AGND. This ensures effective isolation of the analog

modules from noise caused by the digital modules.

The following directives are recommended for the PC87591x power and ground connections (see Figure 11 for the power

supply connections):

Ground Connection

Use two ground planes, one for the digital signals (GND) and one for the analog signals (AGND). The following ground con-

nections should also be made:

●The analog ground plane (AGND) should be connected at only one point to the digital ground plane (GND). This point

should be located physically near the PC87591x.

●The analog ground return pin of the PC87591x (AGND) should be connected to the analog ground plane.

●The decoupling capacitors of the analog supply (AVCC) pin should be connected to the analog ground plane as close

as possible to the AGND pin.

●The ground reference of the voltage input signals to the ADC module (VIN0-9 in Figure 11) should be connected to

the AGND plane close to the PC87591x.

●The ground reference of the voltage output signals from the DAC module (VOUT0-3 in Figure 11) should be connected

to the AGND plane close to the PC87591x.

●All GND pins of the PC87591x must be connected to the GND plane.

●The decoupling capacitors of the Suspend digital supply (VCC) pin should be located near each VCC-GND pin pair;

one side of each capacitor should be connected to the ground plane.

●The ground reference of the voltage input signals to the ACM module (KBVIN0-7 in Figure 11) should be connected

to the GND plane close to the PC87591x.

●The decoupling capacitors of the Host digital supply (VDD) pin should be located near the VDD-GND pair; one side of

each capacitor should be connected to the ground plane.

●The ground return and the decoupling capacitor of the backup battery supply (VBAT) pin should be located near the

PC87591x; one of the capacitor’s sides should be connected to the ground plane.

Note that low-impedance ground layers improve noise isolation and reduce ground bounce problems.

Power Connection

All PC87591x supply pins must be connected to the appropriate power plane, and decoupling capacitors must be used as

recommended below.

The analog supply pin, AVCC, should be connected to a low-noise power supply that has the same voltage as the digital

supply (3.3V). If the AVCC pin is connected to the same power supply as the VCC pin, it is recommended to use an external

LC or RC filter for the AVCC pin. An example of an LC filter [L1and (C1+C2)] is shown in Figure 11. An RC filter is obtained

by replacing L1 (in Figure 11) with a 10Ω resistor (not shown in the figure).

Decoupling Capacitors

The following decoupling capacitors should be used to reduce power supply deeps, ground bounce and EMI (refer to

Figure 11 for the position of capacitors, e.g., C1, C2, etc.):

●Suspend digital supply (VCC): Place one 0.1 µF capacitor (C3) on each VCC-GND pin pair as close as possible to the

pin pair. Also, place one 10−47 µFC

4tantalum capacitor on the common net as close as possible to the chip.

●Host digital supply (VDD): Place one 0.1 µF capacitor (C5) on the VDD-GND pin pair as close as possible to the pin

pair. Also, place one 10-47 µF tantalum capacitor (C6) on the common net as close as possible to the chip.

●Backup battery (VBAT): Place one 0.1 µF capacitor (C7) on the VBAT pin as close as possible to the pin.

●Analog supply (AVCC): Place a 0.1 µF capacitor (C2) and a 10-47 µF tantalum capacitor (C1) on the AVCC pin as

close as possible to the pin.

3.0 Power, Reset and Clocks (Continued)

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PC87591E/S/L

3.2 RESET SOURCES AND TYPES

The PC87591x has several input reset types:

●VPP Power-Up reset (for VPP supplied functions only)

Activated when either VCC or VBAT is powered up after both have been off.

●VCC Power-Up reset

Activated when VCC is powered up.

●Warm reset

Activated on RESET1 input falling edge.

●WATCHDOG and Debugger Interface resets:

—WATCHDOG reset

Activated on request from the TWD module (WATCHDOG signal is asserted); see Section 4.10 on page 164.

—Debugger Interface reset

Activated on request from the Debugger Interface module used during debug and ﬂash updates; see Section 4.19

on page 248.

●Host Domain reset

This is divided into two sub-groups: Host Domain Hardware and Host Domain Software reset. Combinations consist-

ing of the ﬂowing events are used to trigger these reset operations:

—RESET1 active

—When VDD is active, RESET2 is active

—On VDD power-up

—A Software reset triggered by a write of 1 to bit 1 of SIOCF1 register in the SuperI/O Conﬁguration registers; see

Section 6.1.8 on page 343

Unless otherwise noted, reset references throughout the PC87591x modules default to the following types:

●For VPP retained functions: VPP Power-Up reset

●For core domain functions and host-core interface functions: VCC Power-Up reset, Warm reset, WATCHDOG reset,

Debugger Interface reset and Software reset

●For host domain functions: Host Domain reset

VCC

GND

Digital Ground Plane

Analog

AVCC

C3 0.1

0.1 AGND

Analog Ground Plane

Power

AD0

AD9

VIN0

VIN9

VIN

µF

µFµF

10-100 µH

(3.3V)

DA0

DA3

VOUT0

VOUT3

Suspend

Digital

Power

(3.3V)

VDD C5

0.1

µFµF

BAT

VBAT

(3.3V)

Digital

Power

Host

Backup

Power

0.1

µF

PC87591x

Figure 11. PC87591x Power Supply Connection

KBVIN0

KBVIN7 KBVIN

KBSIN0

KBSIN7

3.0 Power, Reset and Clocks (Continued)

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PC87591E/S/L

In DEV environment, the PC87591x outputs to the BRKL_RSTO signal an indication that a reset occurred at the core

domain. See Section 4.20.3 on page 272 for the implementation and usage of RSTO.

The following sections detail the sources and effects of the various resets on the PC87591x, per reset type.

3.2.1 VPP Power-Up Reset

VPP is an internal power signal derived from VCC and VBAT.V

PP Power-Up reset is generated by an internal circuit that de-

tects the status of the VPP power. VPP Power-Up reset signal is active from the rising of VPP until the VPP power is detected

as “good” (i.e., VPP is above VBATDTC). When active, this signal resets all registers whose values are retained by VPP.

For more details, see Section 6.2.9 on page 360.

3.2.2 VCC Power-Up Reset

VCC Power-Up reset is generated by an internal circuit. The PC87591x performs a VCC Power-Up reset when VCC power is

applied. This reset is completed tIRST after the internal clocks have stabilized (see Section 7.6.2 on page 384).

If the 32 KHz crystal is disabled before VCC power-up, external devices should wait at least t32KOSC before accessing the

PC87591x. Any host processor access during this time results in:

●The host processor is stalled (by driving a “Long WAIT sync” response on the LPC bus) until after the reset process

is completed and the bus request can be performed.

●If HRAPU bit in MSWCTL1 register is set (1), the host processor is reset by asserting KBRST until the internal reset

is completed.

On VCC Power-Up reset, the PC87591x responds as follows:

●Enables the 32 KHz crystal, if it is disabled.

●Resets the High-Frequency Clock Generator (HFCG) to its default frequency.

●Loads default values to all registers whose values are retained by VCC.

●Puts pins with strap options into TRI-STATE and enables the internal pull-downs on the strap pins.

●Samples the values of the strap pins.

●Resets the TAP controller of the Debugger Interface module.

●Resets the MSWC, excluding those MSWC registers whose values are retained by VPP

●Resets Port PC0.

●Carries out all the Warm reset actions (see below).

3.2.3 WATCHDOG Reset and Debugger Interface Reset

The PC87591x generates a WATCHDOG reset on request from the TWD module (i.e., a WATCHDOG signal is asserted).

It generates a Debugger Interface reset on request from the Debugger Interface module (reset command). During these re-

sets, the PC87591x performs the VCC Power-Up reset actions, with the following exceptions:

●The PC87591x does not sample the value of any strap pin; instead, it maintains the conﬁguration determined by the

strap pins at VCC Power-Up reset.

●It does not reset the TAP controller.

●On Debugger I/F, reset PC0 is not reset (it is reset on WATCHDOG reset).

●It resets the HFCG to its default frequency.

●Some MSWC registers do not reset on WATCHDOG or Debugger I/F reset.

The reset periods are identical to the VCC Power-Up reset period.

3.2.4 Warm Reset

Warm reset is activated on the falling edge of RESET1 input. If Warm reset and VCC Power-Up reset occur at the same time,

VCC power-up takes precedence.

3.0 Power, Reset and Clocks (Continued)

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PC87591E/S/L

During a Warm reset, the PC87591x responds as follows:

●Terminates core executed instructions

●Discards results not yet written to memory

●Eliminates any pending core interrupts and traps

●Clears the internal latch for the core domain’s edge-sensitive external interrupt

●Deactivates the external bus control signals WR(0-1), SEL(0-1), SELIO, RD and BST(0-2)

●Puts the address A(0-19) and data D(0-15) buses in TRI-STATE

●Switches to core domain’s Active mode

●Loads default values into registers, with the exception of:

—The Mobile System Wake-Up Control (MSWC) and RTC registers retained by VPP

—Some registers that are speciﬁcally noted to be cleared only by other events

●Resets the Debugger interface, except for TAP controller

During Warm reset, strap pins are not sampled and the configuration determined at VCC power-up is unaffected by subse-

quent Warm resets.

The PC87591x core domain and some parts of the host-core interface functions can operate when RESET1 is still asserted

(low). Some parts of the Host Domain Functions that are reset by the Host Domain reset (see following section) are kept

reset as long as RESET1 is asserted.

3.2.5 Host Domain Reset

Using RESET2 Input

The RESET2 input signal is enabled as an alternate function on one of two pins. The Protection Word in the flash memory

is used to define whether the RESET2 input is enabled and, if so, on which of the two pins. See Section 4.16.6 on page 226

for details on RESET2 input configuration.

Note that enabling RESET2 input on either of the signals causes that pin to be used as an input GPIO with an interrupt input

associated with it. It is recommended to use this interrupt function to interrupt the core when a RESET2 event occurs and

to use the interrupt routing to stop activities and resume default values to some system elements not directly reset by the

event.

Host Domain Reset Actions

The reset actions on the host domain are broken into two categories that depend on the reset event source; some of the

actions may happen for both these reset source types and thus are named Host Domain Rest.

Host Domain Hardware Reset: While RESET1 is active, RESET2 is also active if VDD is on or during VDD power-up.

Host Domain Hardware reset performs the following actions:

●It brings the LPC interface state machine to its inactive state.

●It resets all SuperI/O conﬁguration registers except for those that are battery-backed (see Section 6.1.8 on page 343).

●It resets Shared Memory Host Controlled registers

Host Domain Software Reset: This reset is triggered by a write of 1 to bit 1 in SIOCF1 register in the SuperI/O Configura-

tion registers.

Host Domain Software reset performs the following actions:

●It resets all SuperI/O conﬁguration registers except those noted to be protected from software reset (i.e., bits that are

locked from write accesses).

●It resets Mobile System Wake-Up Control (MSWC) bits and RTC bits marked to be reset by software.

Note that lock bits and memory protect bits are not reset by software reset; instead, they require a hardware reset to unlock

them; this requirement protects these bits from any faulty or malicious software.

For more details, see Section 6.1.3 on page 341.

Host Domain Reset: This term is used when a bit is reset by either a Host Domain Hardware reset or Host Domain Soft-

ware reset.

3.0 Power, Reset and Clocks (Continued)

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PC87591E/S/L

3.3 CLOCK DOMAINS

The PC87591x has three clock domains, as shown in Table 12.

Core Domain Clock

The core clock is sourced by the HFCG. The following section gives an overview of the clock domain.

On VCC Power-Up reset, the HFCG is set to generate a 4 MHz clock. The HFCG frequency can be modified by core firm-

ware. See Section 4.18 on page 239.

On WATCHDOG reset (or Debugger interface reset), the HFCG is reset.

LPC Clock

The LPC interface is driven by the LCLK input. LCLK frequency can be up to 33 MHz. The clock CLKRUN signal may be

used as part of a power management scheme that slows the clock down; see “CLKRUN Functionality” on page 343.

RTC (32 KHz) Clock

The RTC clock is the reference for the generation of all other clocks in the PC87591x. The clock is enabled at VCC power-

up and is kept active while VPP is active. Keeping the RTC clock active significantly reduces the PC87591x wake-up time.

The RTC clock is used for time keeping in the RTC; it is also fed into the Power Management Controller (PMC), which pro-

vides the clock to other functions (such as TWD and ACM) that are active at all times (including Idle).

Table 12. PC87591x Clock Domains

Clock Domain Frequency Source Usage

Core See Section 4.18

on page 239 HFCG Core domain and host-core interface

LPC Up to 33 MHz LPC clock input LPC bus interface

RTC 32 KHz Clock input or on-chip oscillator1

1. See Section 6.2.3 on page 356 and Section 6.2.4 on page 357.

RTC, HFCG, TWD, PMC, ACM

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PC87591E/S/L

4.0 Embedded Controller Modules

4.1 BUS INTERFACE UNIT (BIU)

The BIU directly interfaces with a wide variety of devices, including ROM, SRAM and flash memory devices and I/O devices.

It interfaces via address, data and control buses without the need for external glue logic.

The BIU also defines the access time to the on-chip flash Main block to provide cycle-by-cycle compatibility between envi-

ronments; see Section 1.4 on page 29 and “Accessing Base Memory” on page 35. To optimize access time to the on-chip

Base Memory, the Base Memory is split into Fast and Slow Zones. These zones are associated with Zone 1 and Zone 2 of

the BIU, respectively. The SEL1 output signal of the PC87591x is the logical AND of the two SELi outputs of Zones 1 and 2.

4.1.1 Features

●Four address zones for static devices (SRAM, ROM, ﬂash, I/O).

●Basic bus cycle: two clock cycles.

●Conﬁgurable fast read bus cycles with 1-cycle read duration.

●Wait states: conﬁgurable between zero and seven clock cycles.

●Hold cycles: conﬁgurable between zero and three clock cycles.

●I/O expansion support.

●Conﬁgurable burst on read.

●Burst read: one clock cycle.

●Conﬁgurable early write or late write.

●Bus width: conﬁgurable per zone - 16-bit or 8-bit.

4.1.2 Functional Description

Interface

The BIU interfaces between:

●Internal core bus

●External static memory

●Off-chip I/O (memory-mapped) devices

The BIU performs the following functions:

●Distinguishes between four static memory zones

●Selects the relevant conﬁgured parameters of the accessed zone (e.g., the number of wait states)

●Issues the appropriate bus cycle to access the zone

Each memory zone has a different address range and a set of parameters that define access to this zone. The set of pa-

rameters is software configurable.

Static Memory and I/O Support

The BIU accesses static memory devices (ROM, SRAM, flash and I/O devices) using static read and write bus cycles. The

BIU can be configured to extend the bus cycles with wait cycles.

The BIU supports burst read bus cycles if the accessed zone is configured as burstable. (A burst-read bus cycle is an ex-

tension of the basic-read bus cycle in which additional data is accessed. A burst access usually requires only one clock cycle

per additional data item. It may be extended by up to two clock cycles per additional data item.)

To support both I/O and static memory devices that require long hold times at the end of the access, the BIU can be config-

ured to add up to three Thold clock cycles at the end of the bus cycle. In addition, the BIU can be configured to insert a Tidle

clock cycle between two consecutive accesses to different zones.

Byte Access

The internal core bus is 16-bits wide and supports byte and word transactions.

The BIU issues the appropriate bus cycle to access the right bytes, according to the core bus transaction and the memory de-

vice bus width. Table 13 and Table 14 summarize the details:

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PC87591E/S/L

Table 13. Bus Cycles of a 16-Bit Data Bus

Table 14. Bus Cycles of an 8-Bit Data Bus

On write cycles of a single byte, the remaining eight bits of the bus are floating.

On read cycles of a single byte, the remaining eight bits of the bus are ignored. There is no need for external pull-up resistors.

Clock and Bus Cycles

There are two types of bus cycles: data transfer and non-data transfer. Data transfer bus cycles cause transfer of data from

or to the memory device. Non-data transfer bus cycles (described in Section 4.1.9 on page 81) are used for observability of

internal bus transactions and do not involve data transfer from or to external devices.

There are four types of data transfer bus cycles:

●Early write

●Late write

●Normal read

●Fast read

The BIU uses EWR configuration bit in BCFG register to select the early or late write data transfer bus cycle. It uses FRE in

SZCFGn register (where “n” refers to zone 0, 1 or 2) to select normal read or fast read data transfer bus cycles.

The basic late write bus cycle takes two clock cycles. The basic early write bus cycle takes three clock cycles. When the BIU

uses the early write bus cycle, the RD signal is not required for interfacing with the memory device (with the exception of

flash). On reset, the early write bus cycle is configured.

The basic normal read bus cycle takes two clock cycles. Fast read bus cycle always takes one clock cycle. On reset, the

normal read bus cycle is configured.

Notes:

1. In the descriptions that follow, the “n” in SELn signal refers to two of the three available BIU select signals (numbered 0

or 1, corresponding to zone 0 or zone 1 respectively). The third signal is labelled SELIO.

2. For all timing diagrams, the value of BST0-2 depends on the type of core bus transaction.

3. In the following paragraphs, SZCFGn refers to three of the four BIU zone configuration registers (n = 0, 1 or 2) - the fourth

configuration register is labelled IOCFG.

Number of

Bytes Transferred Core

Bus Bytes Address (LSB) Data Bus Pins

1 B0 0 0-7

1 B1 1 8-15

2 B1 B0 0 0-15

2 B1 1 8-15

B0 Then 0 0-7

Number of

Bytes Transferred Core

Bus Bytes Address (LSB) Data Bus Pins

1 B0 0 0-7

1 B1 1 0-7

2 B0 0 0-7

B1 Then 1 0-71

1. Burst bus cycle, if burstable; otherwise, the core transaction is

broken into “basic” bus cycles.

2 B1 1 0-7

B0 Then 0 0-7

4.0 Embedded Controller Modules (Continued)

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PC87591E/S/L

4.1.3 Clock Cycles

Basic Bus Cycle

A basic bus cycle comprises one to three clock cycles (depending on the type of bus cycle). Adding extra wait or hold clock

cycles extends the data transfer bus cycles. Every data transfer bus cycle has the T1 and T2 clock cycles, with the exception

of the fast read bus cycle, which has only one clock cycle (T1-2).

Tidle Cycle Clock cycles that are not used for bus cycles are called Idle clock cycles (Tidle). Tidle cycles are added when the

BIU does not need to generate a bus transaction or as specifically configured pauses between two consecutive transactions.

When more than one Tidle cycle is requested as a pause, the Tidle cycles overlap and only one Tidle cycle is added.

Tidle clock cycles can be inserted between two consecutive accesses in different zones (to allow long hold times or buffer

disable times). To do this, either program IPRE and/or IPST in SZCFGn register (or IPST in IOCFG register); see Figure 18

on page 77.

Tidle clock cycles are also added between an early write and a read bus cycle, and between a late write and a fast read bus

cycle; see Figure 23 on page 80.

T1 Cycle Every bus cycle starts with T1. In this clock cycle, the address of the selected device (either external or internal)

is set on the address pins. Write bus cycles never drive data during T1.

T2 Cycle The read T2 bus cycles always sample the data at the end of T2.

The write T2 bus cycles always drive data during T2. If no Thold clock cycles follow, the data bus is put in TRI-STATE after

the T2 cycle.

T1-2 Cycle The fast read T1-2 bus cycle is a one-cycle read transaction.

At the start of the clock cycle, the address of the selected device is set on the address pins, and the SELn and RD signals

are activated. At the end of the clock cycle, the BIU samples the data.

T3 Cycle Early write bus cycles always have the T3 clock cycle. No other bus cycles have this clock cycle.

At the start of this clock cycle, SELn (or SELIO) is deactivated; then WR0-1 is deactivated. The address and data remains

valid until T3 is completed. If no Thold clock cycles follow, the data bus is put in TRI-STATE after the T3 cycle.

Optional Clock Cycles

The following clock cycles are optional in a data transfer bus cycle:

●TIW (Internal Wait)

●T2B (T2 burst)

●TBW (Burst Wait)

●Thold

TIW Cycle Extend the basic data transfer bus cycle by adding wait clock cycles. To do this, program WAIT in SZCFGn reg-

ister (or IOCFG register) with the required additional wait clock cycles. Wait clock cycles generated by this action are named

TIW (internal wait). TIW cycles are added after T1 and followed by T2 cycles. Data is always driven during wait clock cycles

of a write bus cycle.

T2B Cycle Data of read burst bus cycles is sampled at the end of T2B. If the TBW cycle is not configured, the address is

changed at the start of T2B. Write bus cycles do not have this clock cycle.

TBW Cycle A burst bus cycle can be extended by one wait clock cycle, named TBW. This is done according to WBR in

SZCFGn register. The address is changed at the start of TBW. Write bus cycles do not have this clock cycle.

Thold Cycle Hold cycles are added after T2 or T2B (if there is a burst bus cycle) or T3 (according to HOLD in SZCFGn or

IOCFG register); the address and data (during a write bus cycle) are always valid during these cycles. The data bus is put

in TRI-STATE after the last Thold.

Other Clock Cycles

Special Tidle Cycle During Tidle cycles, one of the SEL0-1 signals and the RD signal may be activated for one clock cycle.

This happens due to special activity on the internal core bus. To avoid contention on the memory bus, it is guaranteed that

this clock cycle is followed by a sufficient number of Tidle cycles before the next T1 cycle is performed.

The number of Tidle cycles that follows is at least the number required by the selected zone as configured in HOLD field in

SZCFGn register.

4.0 Embedded Controller Modules (Continued)

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PC87591E/S/L

Burst Read Cycles A read bus cycle consisting of the basic bus cycle plus additional clock cycles called “burst bus cycles”.

The burst bus cycles occur if the bus is burstable (BRE in SZCFGn register is 1), the configured bus width is eight bits and

the core attempts to read a word. When the bus is not burstable (BRE in SZCFGn register is 0), the BIU issues two separate

read bus cycles. Write bus cycles are never burstable, and the BIU always issues two separate write bus cycles.

Control Signals

The write bus cycles use byte write qualifiers on WR0-1 pins:

●They access an 8-bit wide memory on D0-7 data lines.

One byte is accessed on basic bus cycles. Only the WR0 pin is used as the byte write qualiﬁer.

●They access a 16-bit wide memory on D0-15 data lines.

Either one or two bytes are accessed on basic bus cycles. The WR0 pin is used as an even byte (D0-7) write qualiﬁer

and WR1 pin is used as an odd byte (D8-15) write qualiﬁer.

4.1.4 Early Write Bus Cycle

If EWR in BCFG register is 1, the BIU uses early write bus cycles. This allows removal of the RD signal from the memory

device interface. The basic early write bus cycle takes three clock cycles.

The cycle starts at T1; at this point, the data bus is in TRI-STATE, the address is placed on the address bus and RD is in-

active. indicating that this is a write bus cycle. Then, WR0-1 are activated.

At the first TIW or T2 (when there are no TIW cycles), the data is placed on the data bus and the SELn (or SELIO) is acti-

vated. The bus transaction is terminated at T3; at this point, SELn (or SELIO) becomes inactive. Then WR0-1 become in-

active and the data bus is put in TRI-STATE. The address remains valid until T3 is complete.

Thold clock cycles may follow T3, according to HOLD in SZCFGn or IOCFG registers (may be 0). The address and data re-

main valid until the end of the last Thold cycle. The data is put in TRI-STATE in the clock cycle after the last Thold or T3 (if no

Thold cycle is configured); see Figures 12, 13 and 14.

If a read bus cycle immediately follows an Early Write bus cycle, an idle cycle is added between the two.

4.0 Embedded Controller Modules (Continued)

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HOLD field in SZCFGn reg. ≠ 0

WAIT field in SZCFGn reg. ≠ 0

SELn: inactive, WR0-1: inactive;

if HOLD field in SZCFGn reg. = 0 data put in TRI-STATE.

WAIT field in SZCFGn reg. = 0

Hold cycles completed

Address placed on A0-19,

WR0-1: activated

Data placed

on D0-15,

SELn: active Internal waits completed

HOLD in SZCFGn reg. = 0

Address on A0-19 invalid/changed

Data put in TRI-STATE

Data placed on D0-15,

SELn: active

Internal waits corresponding to Wait field in SZCFGn register.

Thold Hold cycles according to HOLD field

in SZCFGn reg.

TIW

end

begin

Note: References to SZCFGn also apply to the IOCFG register.

References to SELn also apply to the SELIO signal.

Figure 12. Early Write Bus Cycle

4.0 Embedded Controller Modules (Continued)

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PC87591E/S/L

4.1.5 Late Write Bus Cycle

If EWR in BCFG register is 0, the BIU uses the late write bus cycle. The basic late write bus cycle takes two clock cycles.

This write bus cycle requires the RD signal in the memory device interface.

A write bus cycle starts at T1. When the data bus is in TRI-STATE, the address is placed on the address bus and SELn (or

SELIO) is activated. Next, WR0-1 are activated. RD is inactive to indicate this is a write transaction.

CLK

A0-19

SELx

SELy

WR0-1

D0-15

Normal Read Early Write Read,

T1 T2 T1 T2 T1 T2

All Other Zones

In In

BST0-2 (Note)

(x ≠y)

(y ≠x)

Out

Figure 13. Early Write Following Normal Read with 0 Wait

Bus State

CLK

A0-19

SELn

WR0-1

D0-15

T1 TIW T2 T3 THold

Out

BST0-2

Figure 14. Early Write Bus Cycle with 1 Internal Wait and 1 Hold

Bus State

4.0 Embedded Controller Modules (Continued)

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PC87591E/S/L

At the first TIW or T2 (when there are no TIW cycles), the data is placed on the data bus. The bus cycle is completed at T2;

at this point, WR0-1 are deactivated. The address and data remain valid until T2 is completed.

After T2, the number of Thold cycles specified by HOLD in SZCFGn register (may be 0) is added to the transaction. When

Thold cycles are added, the address and data remain valid until the end of the last Thold cycle. SELn (or SELIO) is deactivated

on the first Thold cycle. When no Thold cycles are specified, SELn (or SELIO) is deactivated in the clock cycle after T2 unless

another read or write from the same zone follows. The data is put in TRI-STATE in the clock cycle after the last Thold or T2

(if no Thold cycle is configured); see Figures 15, 16 and 17.

Hold cycles

according to

HOLD in

SZCFGn reg.

HOLD field in SZCFGn reg. ≠ 0

WAIT field in SZCFGn reg. ≠ 0 WAIT field in SZCFGn reg. = 0

First Thold;

SELn: inactive.

Hold cycles completed

Address placed on A0-19;

SELn: activated;

WR0-1: activated.

Data placed

on D0-15

Internal waits completed

HOLD field in SZCFGn reg. = 0

Address on A0-19 invalid/changed;

Data put in TRI-STATE;

SELn: inactive.

Data placed on D0-15;

WR0-1: inactive.

Internal waits corresponding to WAIT field in SZCFGn register

Thold

end

begin

Note: References to SZCFGn also apply to the IOCFG register.

References to SELn also apply to the SELIO signal.

TIW

Figure 15. Late Write Bus Cycle

4.0 Embedded Controller Modules (Continued)

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PC87591E/S/L

4.1.6 Normal Read Bus Cycle

A read bus cycle starts at T1; at this point, the address is placed on the address bus, SELn (or SELIO) is activated and

WR0-1 are inactive, indicating that this is a read bus cycle. The RD signal is activated on the first TIW or T2 (when there are

no TIW cycles).

At the end of T2, the BIU samples the data on D0-7 or D0-15, according to BW signal in SZCFGn register. After T2, the

number of Thold cycles specified by HOLD in SZCFGn register (may be 0) is added. SELn and RD are deactivated on the

first Thold cycle. The address remains valid until the end of the last Thold cycle.

CLK

A0-19

SEL0-1,

D0-15

WR0-1

Normal Read Late Write Normal Read

T1 T2 T1 T2 T1 T2

Bus State

In Out In

BST0-2

SELIO

Figure 16. Late Write Bus Cycle Between Normal Read Bus Cycles with 0 Wait

CLK

A0-19

SELn

D0-15

WR0-1

Bus State T1 TIW T2 Thold

BST0-2

Figure 17. Late Write Bus Cycle with 1 Internal Wait and 1 Hold

Out

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When no Thold cycles are specified, SELn is deactivated in the clock cycle that follows T2, unless another read from the

same zone follows. The RD signal is always deactivated in the clock cycle following T2; see Figures 18, 19 and 20.

A burst bus cycle supplements the basic read bus cycle if the core attempts to access more bytes (i.e., a word) than the

configured bus width (and BRE in SZCFGn register is set to 1). The burst bus cycle (T2B) follows T2 before the Thold cycles

(if configured). A wait clock cycle (TBW) is added between T2 and T2B if WBR in SZCFGn register is set to 1.

The address of the burst bus cycle is changed on TBW (if configured) or T2B (if no TBW). At the end of T2B, data is sampled.

The RD signal is activated during the burst bus cycle and is deactivated in the clock cycle following T2B; see Figures 21 and

22.

CLK

A0-19

SELx

SELy

WR0-1

D0-15

Normal Read

T1 T2 TIdle T1 T2

In In

(x ≠y)

(y ≠x)

BST0-2

Figure 18. Two Basic Normal Read Bus Cycles with Idle In Between (IPST Bit in SZCFGy Register = 1,

IPRE Bit in SZCFGx Register = 1)

Bus State

CLK

A0-19

SELn

D0-15

WR0-1

Bus State T1 TIW TIW T2 THold

BST0-2

Figure 19. Normal Read Bus Cycle with 2 Internal Waits and 1 Hold

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Other SZCFGn

configuration

HOLD field in SZCFGn reg. = 0

HOLD field in SZCFGn reg. ≠ 0

WAIT field in SZCFGn reg. ≠ 0 WAIT field in SZCFGn reg. = 0

Address placed on A0-19;

SELn: activated.

RD: active

Address on A0-19 invalid/changed;

SELn and RD: inactive.

RD: active;

End of T2: Data is sampled.

Internal waits corresponding to WAIT field in SZCFGn register.

TIW

TBW

begin

Hold cycles completed

Thold

T2B

end

{BW = 1 or BRE = 0

or core attempts to read a byte}

BW = 0; {WBR,BRE} = 11;

Core attempts to read a word

Next address on A0-19;

End of T2B: Data sampled.

Hold cycles according

to HOLD field in SZCFGn reg.

First Thold: SELn

and RD are deactivated

In SZCFGn reg.: {BW,WBR,BRE} = 001

Core attempts to read a word

Figure 20. Normal Read Bus Cycle

Note: References to SZCFGn also apply to the IOCFG register.

References to SELn also apply to the SELIO signal.

TBW and T2B states do not exist in bus cycles of the IO zone.

Internal waits completed

In SZCFGn reg.: HOLD ≠ 0

Next address

on A0-19

In SZCFGn reg.:

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4.1.7 Fast Read Bus Cycle

When FRE bit in SZCFGn register is 1, the fast read bus cycle is enabled for zone n. The fast read bus cycle takes one clock

cycle.

At the start of the T1-2 clock cycle, the address is placed on the address bus, and SELn and RD are activated. WR0-1 are

inactive, indicating a read bus cycle. At the end of the clock cycle, the BIU samples the data. SELn and RD are deactivated

in the following clock cycle, unless another read from the same zone follows. If a write to the same zone follows and late

write is configured, SELn remains activated. The address remains valid until the start of the clock cycle after the T1-2 clock

cycle.

CLK

A0-19

SELn

D0-7

WR0-1

Bus State T1 T2 T2B

In In

BST0-2

Figure 21. Normal Read Bus Cycle with 0 Wait on Burst

CLK

A0-19

WR0-1

D0-7

T1 TIW TIW T2 TBW

SELn

T2B

BST0-2

Figure 22. Normal Read Bus Cycle with 2 Internal Waits and 1 Wait on Burst

Bus State

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The fast read bus cycle cannot be extended by adding wait cycles (WAIT field in SZCFGn register is ignored during this bus

cycle). Additionally, hold cycles cannot be added (HOLD field in SZCFGn register is also ignored). When a write bus cycle

immediately precedes, in sequence, a fast read bus cycle, an idle clock cycle is forced between the two; see Figure 23.

Note that when the core attempts to access more bytes than the configured bus width (i.e., a word), the transaction is broken

up into “basic” (T1-2) bus cycles.

4.1.8 I/O Expansion Bus Cycles

The I/O expansion bus cycles support the implementation of on-chip I/O port functionality (when the pins of the on-chip I/O

ports are used to support DEV environments) and/or additional ports, using off-chip external logic.

I/O expansion bus cycles access the off-chip I/O device using the following signals:

●SELIO.

●Address lines A0-7.

●The RD and WR0-1 signals may be used.

The design minimizes the off-chip logic required to implement the I/O ports. It is costly to implement a port with pins individ-

ually configured for input or output. Implementing ports for input only or output only reduces expenses.

I/O expansion bus cycle is not generated during an access to a port register if one of the following conditions occurs:

●A port pin is available on-chip.

●All port pins are inputs and the port is being written.

CLK

A0-19

SELx

SELy

WR0-1

D0-15

Fast Late Write Fast

TIdle T1-2 T1 T2 T1-2 T1

Read Read

TIdle

In Out In

BST0-2

(x ≠y)

(y ≠x)

Idle

Cycle

Figure 23. Fast Read Bus Cycle

Bus State

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I/O Expansion Read/Write Bus Cycle

These cycles are always preceded by a Tidle clock cycle (see Figure 24). The I/O zone is not burstable.

I/O Expansion Example

Figure 25 shows an example of how two ports can be implemented off-chip, using I/O expansion. This example implements

two 8-bit ports by connecting the SELIO, RD and WR0 pins to the latch/buffer controls.

4.1.9 Development Support

The BIU provides the following support for development systems.

Bus Status Signals

The Bus Status BST0-2 signals indicate whether a transaction on the core bus was issued; they also indicate the transaction

type; see Table 41 on page 273.

CLK

A0-19

SELIO

WR0-1

D0-15

Read Write

TIdle T1 T2 TIdle T2 T3T1

In Out

BST0-2

Figure 24. I/O Expansion Bus Cycles (EWR bit in BCFG Register = 1)

Bus State

SELIO174x377

74x541

OE1

OE2

WR01

CP 8-Bit

8-Bit

Buffer

Figure 25. Example of an Implementation of Two Ports Using I/O Expansion

D0-7 Latch

PC87591x

1. This routing is for late write. If early write, SELIO is routed

to CP and WR0 to CE. All other routing is unchanged.

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Core Bus Monitoring

The core bus monitoring cycle is a non-data transfer bus cycle. It takes a single clock cycle - T1. On this cycle:

●The address pins display the address of the internal device accessed on the core bus.

●CBRD indicates the direction of the access (read or write).

●BE0-1 indicate which data bus bytes are accessed (lower or upper).

●BST0-2 display the core bus status.

The core bus monitoring cycle, as shown in Figure 26, is generated only when bit 1 (OBR) in BCFG register is 1.

CLK

A0-12,

SEL0-1

WR0-1

D0-15

BST0-2

SELIO

A16-19

CBRD

BE0-1

Figure 26. Core Bus Monitoring Bus Cycle

Bus State

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4.1.10 BIU Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

BIU Register Map

BIU Conﬁguration Register (BCFG)

The BCFG register controls the configuration of common features to all zones. On reset, this register is initialized to 0716.

Location: Index 00 F98016

Type: R/W

Mnemonic Register Name Type

BCFG BIU Conﬁguration R/W

IOCFG I/O Zone Conﬁguration R/W

SZCFGn Static Zone Conﬁguration R/W

Bit 76543210

Name Reserved ISTL OBR EWR

Reset 00000111

Bit Description

0EWR (Early Write).

0: Late write

1: Early write

1OBR (Observability). Determines if the address and status of internal accesses are observable.

0: Not observable (no toggle of external buses)

1: Observable (external buses toggle)

2ISTL (Internal Stall). Determines if the internal bus is stalled while the BIU is busy.

0: Internal bus activity not stalled when BIU is busy

1: Stall internal bus activity when the external bus is busy

7-3 Reserved.

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I/O Zone Conﬁguration Register (IOCFG)

The IOCFG register controls the configuration of the I/O zone. On reset, it is initialized to 069F16.

Location: 00 F98216

Type: R/W

Bit 1514131211109876543210

Name Reserved IPST Res BW Reserved HOLD WAIT

Reset 0000011010011111

Bit Description

2-0 WAIT. Number of TIW clock cycles that extend the bus cycle.

Bits

2 1 0 Number

0 0 0: None

0 0 1: One

0 1 0: Two

0 1 1: Three

1 0 0: Four

1 0 1: Five

1 1 0: Six

1 1 1: Seven

4-3 HOLD. Number of Thold clock cycles.

Bits

4 3 Number

0 0: None

0 1: One

1 0: Two

1 1: Three

6-5 Reserved.

7Bus Width. Sets the external bus width used for the I/O zone. It is initialized during reset to its default value.

0: 8-bit bus

1: 16-bit bus (default)

8Reserved.

9IPST (Idle After Bus Cycle). Determines if an idle cycle follows the current bus cycle when the next bus cycle

is in a different zone.

0: No idle cycle inserted

1: Idle cycle inserted

15-10 Reserved.

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Static Zone Conﬁguration Register (SZCFGn)

The SZCFGn register (where n = 0, 1 or 2) controls the configuration of zone n. On reset, SZCFGn is initialized to 069F16.

Location: Zone 0 - 00 F98416

Zone 1 - 00 F98616

Zone 2 - 00 F98816

Type: R/W

Bit 1514131211109876543210

Name Reserved FRE IPRE IPST Res BW WBR BRE HOLD WAIT

Reset 0000011010011111

Bit Description

2-0 WAIT. Number of TIW clock cycles that extend the bus cycle. Ignored when bit 11 (FRE) of this register is set

to 1.

Bits

2 1 0 Number

0 0 0: None

0 0 1: One

0 1 0: Two

0 1 1: Three

1 0 0: Four

1 0 1: Five

1 1 0: Six

1 1 1: Seven

4-3 HOLD. Number of Thold clock cycles.

Bits

4 3 Number

0 0: None

0 1: One

1 0: Two

1 1: Three

5BRE (Burst Read Enable). Ignored when bit 11 (FRE) of this register is set to 1.

0: Disabled

1: Enabled

6WBR (Wait on Burst Read). Determines if a wait state (TBW) is added on a burst read transaction.

0: No TBW

1: TBW

7BW (Bus Width). Sets the external bus width used for the I/O zone. It is initialized during reset to its default

value.

0: 8-bit bus

1: 16-bit bus (default)

8Reserved.

9IPST (Idle After Bus Cycle). Determines if an idle cycle follows the current bus cycle when the next bus cycle

is in a different zone.

0: No idle cycle inserted

1: Idle cycle inserted

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4.1.11 Usage Hints

The following usage hints help configure the BIU to maximize PC87591x performance and avoid contention on the data bus.

1. In IRE environment, access time to the internal flash can use zero wait and zero hold cycles or fast reads depending on

the CLK frequency set for the core and its peripherals (see “Flash Read, Write and Erase Time” on page 222).

Flash sections 0 and 1 (fast zone) and Section 2 (slow zone) can use a fast read bus cycle through the operation fre-

quency of the PC87591x; therefore, program SZCFG1 fields to be: WAIT=000, HOLD=00, BRE=0, WBE=0, BW=1,

FRE=1.

When Section 2 (slow zone) can operate with a fast read bus cycle, program SZCFG2 fields to be: WAIT=000,

HOLD=00, BRE=0, WBE=0, BW=1, FRE=1.

When Section 2 (slow zone) needs to operate with normal read and zero wait, program SZCFG2 fields to be: WAIT =000,

HOLD=00, BRE=0, WBE=0, BW=1, FRE=0.

2. To avoid contention on the data bus when a read bus cycle (no Thold clock cycles) in one zone is followed by a read bus

cycle in another zone, program IPST and IPRE in the different memory (I/O) zones as follows:

10 IPRE (Idle Before Bus Cycle). Inserts an idle cycle before the current bus cycle when this bus cycle is in a new

zone.

0: No idle cycle inserted

1: Idle cycle inserted

11 FRE (Fast Read Enable).

0: Disabled - Normal read bus cycle takes at least two clock cycles

1: Enabled - Normal read bus cycle takes one clock cycle

15-12 Reserved.

Zone IPRE IPST

Zone 0 0 0

Zone 1 1 0

Zone 2 0/11

1. Set IPRE when the zone is con-

ﬁgured for fast read.

Zone I/O 12

2. An IPRE is forced always for

Zone I/O.

Bit Description

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4.2 DMA CONTROLLER (DMAC)

The DMAC transfers blocks of data between memory and I/O devices along four independent channels, with minimal inter-

vention by the core. The source and destination addresses and the block size to be transferred may be defined for each of

the channels.

4.2.1 Features

●Four Independent Direct Memory Access (DMA) channels.

●Direct (ﬂy-by) and indirect (memory-to-memory) transfer types.

●Single-buffer, double-buffer and auto initialize operation modes.

●Fixed address (I/O device) or updated (memory device).

●Address update (increment or decrement) independent of the number of transferred bytes.

●Interrupt line for each channel.

●Programmable bus policy for each channel: continuous or intermittent use of the bus.

●Software DMA request for each channel.

●Maximum throughput in direct (ﬂy-by) transfer:

—Intermittent:Every three clock cycles.

—Continuous:On internal core bus - every clock cycle.

—Otherwise:Every two clock cycles.

●Maximum throughput in indirect (memory-to-memory) transfer:

—Intermittent:Every ﬁve clock cycles.

—Continuous:On internal core bus - every two clock cycles.

—Otherwise:Every four clock cycles.

4.2.2 Functional Description

When transferring blocks of data using the DMAC, the source and destination addresses, as well as the block size and type

of operation, are set up in advance by programing the appropriate control registers. Actual data transfers are handled by the

DMAC channel in response to DMA transfer requests. On receiving a DMA transfer request (DMRQn), if the channel is en-

abled, the DMAC performs the following operations:

1. Acquires control of the core bus according to the DMAC priority on the core bus.

2. Determines priority among the DMAC channels, one clock cycle before T1 of the DMAC transfer cycle. (T1 is the first

clock cycle of the bus cycle.) Priority among the DMAC channels is fixed in descending order, with Channel 0 receiving

the highest priority.

3. Executes data transfer bus cycle(s) according to the values stored in the control registers of the channel being serviced

and according to the accessed memory address. It acknowledges the request during the bus cycle that accesses the

requesting device.

4. If the transfer of a block is terminated, the DMAC does the following:

—Updates the termination ﬂags.

—Generates an interrupt if enabled.

—Goes to step 6.

5. If DMRQn is still active and the Bus Policy is “continuous”, returns to step 3.

6. Relinquishes the internal core bus.

Each DMAC channel can be programed for direct (fly-by) or indirect (memory-to-memory) data transfer. Once a DMAC

transfer cycle is in process, the next transfer request is sampled when the DMAC acknowledge is deactivated and subse-

quently, on the rising edge of each clock cycle.

The configuration of either address freeze or address update (increment or decrement) is independent of the number of

transferred bytes, transfer direction or number of bytes in each DMAC transfer cycle. All these can be configured for each

channel by programing the appropriate control registers.

Each DMAC channel has eight control registers. DMAC channels are described hereafter with the suffix “n”, where n repre-

sents the channel number in the register name (n = 0 to 3).

4.2.3 Channel Assignment in PC87591x

Table 15 shows the assignment of the DMA channels to different tasks in the PC87591x. If a channel is used for memory

block transfers, other resources must be disabled.

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Table 15. DMA Channel Assignment

4.2.4 Transfer Types

The DMAC uses two data transfer modes, direct (fly-by)and indirect (memory-to-memory).The choice of mode depends on

the correlation between the source and destination bus lengths, the required bus performance and the peripheral structure

(as indicated in Table 15).

Direct (Fly-By) Transfers

Figure 27. DMAC Direct Bus Cycle Followed by a Core Bus Cycle

In Direct mode, each data item is transferred using a single bus cycle without reading the data into the DMAC. It provides

the fastest transfer rate, but it requires identical source and destination bus widths.

Data transfer cannot occur between two memory elements. One of the elements must be the I/O device that requested the

DMA transfer. This device is referred to as the implied I/O device. The other element can be either memory or another I/O

device and is referred to as the addressed I/O device.

The appropriate DMA acknowledge signal for each channel is asserted during the bus cycle.

If the bus policy is “intermittent”, maximum throughput is one transaction every three clock cycles. If bus policy is “continu-

ous”, maximum throughput on the internal core bus is one transaction every two clock cycles.

Since only one address is required in Direct mode, this address is taken from the corresponding ADCAn counter. The DMAC

Channel generates either a read or a write bus cycle according to the setting of DIR bit in DMACNTLn register.

When DIR bit is 0, a read bus cycle from the addressed device is performed, and the data is written to the implied I/O device.

When DIR bit is 1, a write bus cycle to the addressed device is performed, and the data is read from the implied I/O device.

The configuration of either address freeze or address update (increment or decrement) is independent of the number of

transferred bytes, transfer direction, or number of bytes in each DMAC transfer cycle. All these can be configured for each

channel by programing the appropriate control register.

The number of bytes transferred in each cycle is taken from TCS bit in DMACNTLn register. After the data item has been

transferred, the BLTCn counter is decremented by one. The ADCAn counter are updated according to INCAn field and ADA

bit in DMACNTLn register.

Channel Usage Mode Enable Control Interrupt

0 USART Receive Indirect USART registers DMA_INT0

1 USART Transmit Indirect USART registers DMA_INT1

2 Reserved Indirect

3 Reserved Indirect

CLK

DMRQi

ADDR

DMACKi

T1 T2 Tidle T1Bus State

ADCA

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Indirect (Memory-to-Memory) Transfers

Figure 28. Indirect Bus Cycle (DIR=0) - External Bus

Figure 29. Indirect Bus Cycle (DIR=1) - External Bus

In Indirect (Memory-to-Memory) mode, data transfers use two consecutive bus cycles. The data is first read into a temporary

register and subsequently written into the destination. This mode is slower than Direct (Fly-By) mode, but it provides support

for different source and destination bus widths.

Indirect mode also facilitates block transfers between two memory elements. Each element is an addressed device and can

be either memory or an I/O device.

The appropriate DMA acknowledge signal for each channel is asserted during the Device B bus cycle.

If the bus policy is “intermittent”, maximum, throughput is every five clock cycles. If the bus policy is “continuous”, maximum

throughput is every two clock cycles on the internal core bus (otherwise, it uses four clock cycles).

When DIR bit is 0, the first bus cycle reads data from the source using the ADCAn counter, and the second bus cycle writes

the data into the destination using the ADCBn counter. When DIR bit is 1, the first bus cycle reads data from the source

using the ADCBn counter, and the second bus cycle writes the data into the destination using the ADCAn counter.

The number of bytes transferred in each cycle is taken from TCS bit in DMACNTLn register. After the data item has been

transferred, the BLTCn counter is decremented by one. The ADCAn and ADCBn counters are updated according to INCAn,

INCBn, ADA and ADB fields in DMACNTLn register.

Note:

For transfer operations between two memory areas, see “Software DMA Request” on page 92.

CLK

DMRQi

ADDR

DMACKi

T1 T2 T1 T2Bus State

ADCA ADCB

Tidle

CLK

DMRQi

ADDR

DMACKi

T1 T2 T1 T2Bus State

ADCB ADCA

Tidle

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4.2.5 Bus Policy

Intermittent Operation Mode

Figure 30. DMAC Direct Bus Cycles in Intermittent Mode, DMRQ Asserted Constantly.

When BPC bit in DMACNTLn is 0, channel n is in Intermittent mode. In this mode, the DMAC channel relinquishes the bus

after each transaction, regardless of the state of its DMA request input. In this way, the DMAC gives the core (and other

DMA channels) a chance to use the bus, even if a DMA device needs the bus for multiple transfers.

Continuous Operation Mode

Figure 31. DMAC Direct Bus Cycles in Continuous Mode - External Bus

When BPC bit in DMACNTLn register is 1, channel n is in Continuous mode. In this mode, a DMAC channel uses the bus

continuously, as long as its request is active and BLTCn > 0. This allows the channel to utilize the full bandwidth of the bus.

The activity of this channel cannot be interrupted by any other internal bus master, including higher priority DMAC channels.

It is the system designer’s responsibility to limit the duration of the DMA request to prevent bus starvation.

CLK

DMRQi

ADDR

DMACKi

T1 T2 T1 T2 TidleBus State

ADCA ADCA

Tidle

Core Cycle Address

CLK

DMRQi

ADDR

DMACKi

T1 T2 T2 Tidle T1Bus State

ADCA

Core Cycle Address ADCA

Embedded Controller Modules (Continued)

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4.2.6 Operation Modes

The DMAC operates in three different block transfer modes - single transfer, double buffer and auto-initialize. Select the ap-

propriate mode according to the character of the block transfer.

Single Transfer Operation

This mode provides the simplest way to accomplish a single block data transfer.

Initialization

1. Write the two block transfer addresses and byte count into the corresponding ADCAn, ADCBn and BLTCn counters, re-

spectively. The BLTCn counter should be written last.

2. Program the OT bit for Non-Auto-Initialize mode, and clear EOVR bit in DMACNTLn register to 0. Clear to 0 VLD bit in

DMASTATn register.

3. Set CHEN bit in DMACNTLn register to 1; the channel activates and responds to DMAC transfer requests.

Termination

When the BLTCn counter reaches 0:

●The transfer operation terminates.

●TC bit in DMASTATn register is set to 1, and CHAC is cleared to 0.

●A level interrupt is generated (if enabled by ETC bit in DMACNTLn register).

Double Buffer Operation

This mode allows the software to set up the next block transfer specification while the current block transfer proceeds. This

mode is used for preparing the next buffer for use in a multi-buffer operation (e.g., the alternate buffer in a double-buffer

scheme).

Initialization

1. Write the two block transfer addresses and byte count into the ADCAn, ADCBn and BLTCn counters, respectively. The

BLTCn counter should be written last.

2. Program OT bit in DMACNTLn register for Non-Auto-Initialize mode.

3. Set CHEN bit in DMACNTLn register to 1; the channel activates and responds to DMAC transfer requests.

4. While the current block transfer proceeds, write the addresses and byte count for the next block into the ADRAn, ADRBn

and BLTRn registers. The BLTRn register should be written last.

Continuation / Termination

When the BLTCn counter reaches 0:

●TC bit in DMASTATn register is set to 1.

●A level interrupt is generated (if enabled by ETC bit in DMACNTLn register).

●The DMAC channel checks the value of VLD bit.

If VLD bit is 1:

●The channel copies the ADRAn, ADRBn and BLTRn values into ADCAn, ADCBn and BLTCn. The BLTCn counter

should be written last.

●Clears VLD bit to 0.

●Becomes ready to start the next block transfer (on the next DMA request).

If VLD bit is 0:

●The transfer operation terminates.

●The channel sets OVR bit in DMASTATn register to 1.

●Clears CHAC bit to 0.

●A level interrupt is generated (if enabled by EOVR bit in DMACNTLn register).

Note:

ADCB and ADRBn are used only in indirect (memory-to-memory)transfer. In Direct (Fly-By) mode, the DMAC does not use

them and therefore does not copy ADRBn into ADCBn.

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Auto-Initialize Operation

This mode allows the DMAC to continuously fill the same memory area without software intervention.

Initialization

1. Write the two block addresses and byte count into the ADCAn, ADCBn and BLTCn counters, respectively (the BLTCn

counter should be written last); also write them to the ADRAn, ADRBn and BLTRn registers, respectively (the BLTRn

counter should be written last).

2. Program OT bit in DMACNTLn register for Auto-Initialize mode.

3. Set CHEN bit in DMACNTLn register to 1; the channel activates and responds to DMAC transfer requests.

Continuation

When the BLTCn counter reaches 0:

●The contents of the ADRAn, ADRBn and BLTRn registers are copied to the ADCAn, ADCBn and BLTCn counters,

respectively. The BLTCn counter should be written last.

●The DMAC channel checks the value of TC bit.

If TC bit is 1:

●OVR bit in DMASTATn register is set to 1.

●A level interrupt is generated (if enabled by EOVR bit in DMACNTLn register).

●The operation is repeated.

If TC bit is 0:

●TC bit in DMASTATn register is set to 1.

●A level interrupt is generated (if enabled by ETC bit in DMACNTLn register).

●The operation is repeated.

4.2.7 Software DMA Request

In addition to the DMRQn signals, a DMA transfer request can also be initiated by software. The software DMA transfer re-

quest is used for memory-to-memory block copying (in indirect transfers).

When SWRQ bit in DMACNTLn register is 1, the corresponding DMA channel receives a DMA transfer request. When

SWRQ bit is 0, the software DMA transfer request of the corresponding channel is inactive.

For each channel, use the software DMA transfer request, only when the corresponding DMRQn signal is inactive.

4.2.8 DMAC Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

DMAC Register Map

Note:

Unless stated otherwise, bits 21 to 31 are reserved in each of the following registers. Double-word (32-bit) registers may be

accessed word-by-word (word aligned).

Mnemonic Register Name Type

ADCAn Device A Address Counter Register R/W

ADRAn Device A Address Register R/W

ADCBn Device B Address Counter Register R/W

ADRBn Device B Address Register R/W

BLTCn Block Length Counter Register R/W

BLTRn Block Length Register R/W

DMACNTLn DMA Control Register R/W

DMASTATn Status Register R/W

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Device A Address Counter Register (ADCAn)

A double-word, read/write register. Holds the current address of either the source data item or the destination location, ac-

cording to DIR bit in DMACNTLn register. ADCAn is updated after each transfer cycle by INCAn, INCBn, ADA and ADB in

DMACNTLn register.

Location: Channel 0 - 00 FA0016

Channel 1 - 00 FA2016

Channel 2 - 00 FA4016

Channel 3 - 00 FA6016

Type: R/W

Device A Address Register (ADRAn)

A double-word, read/write register. Holds the starting address of either the next source data block, or the next destination data

area, according to DIR bit in DMACNTLn register.

Location: Channel 0 - 00 FA0416

Channel 1 - 00 FA2416

Channel 2 - 00 FA4416

Channel 3 - 00 FA6416

Type: R/W

Device B Address Counter Register (ADCBn)

A double-word, read/write register. Holds the current address of either the source data item, or the destination location, ac-

cording to DIR bit in DMACNTLn register. ADCBn is updated after each transfer cycle by INCAn, INCBn, ADA and ADB in

DMACNTLn register. In Direct (Fly-By) mode, this register is not used.

Location: Channel 0 - 00 FA0816

Channel 1 - 00 FA2816

Channel 2 - 00 FA4816

Channel 3 - 00 FA6816

Type: R/W

Device B Address Register (ADRBn)

A double-word, read/write register. Holds the starting address of either the next source data block or the next destination

data area, according to DIR bit in DMACNTLn register. In Direct (Fly-By) mode, this register is not used.

Location: Channel 0 - 00 FA0C16

Channel 1 - 00 FA2C16

Channel 2 - 00 FA4C16

Channel 3 - 00 FA6C16

Type: R/W

Bit 313029282726252423222120191817161514131211109876543210

Name Device A Address Counter

Bit 313029282726252423222120191817161514131211109876543210

Name Device A Address

Bit 313029282726252423222120191817161514131211109876543210

Name Device B Address Counter

Bit 313029282726252423222120191817161514131211109876543210

Name Device B Address

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Block Length Counter Register (BLTCn)

A double-word, read/write register. Holds the current number of DMA transfers to be executed in the current block. BLTCn

is decremented by one after each transfer cycle. A DMA transfer may consist of one or two bytes according to TCS bit in

DMACNTLn register.

Location: Channel 0 - 00 FA1016

Channel 1 - 00 FA3016

Channel 2 - 00 FA5016

Channel 3 - 00 FA7016

Type: R/W

Note: Writing 0 to Block Length Counter field of BLTCn initializes the DMA for 221-1 transfers.

Block Length Register (BLTRn)

A double-word, read/write register. Holds the number of DMA transfers to be executed in the next block. Writing this register,

sets VLD bit in DMASTATn register to 1.

Location: Channel 0 - 00 FA1416

Channel 1 - 00 FA3416

Channel 2 - 00 FA5416

Channel 3 - 00 FA7416

Type: R/W

Note: writing 0 to Block Length field of BLTRn initializes the DMA for 221-1 transfers.

DMA Control Register (DMACNTLn)

A word-wide, read/write register that synchronizes the channel’s operation with the programing of the block transfer param-

eters. On reset, the implemented bits are initialized to 0.

The format of the DMACNTLn register is shown below.

Location: Channel 0 - 00 FA1C16

Channel 1 - 00 FA3C16

Channel 2 - 00 FA5C16

Channel 3 - 00 FA7C16

Type: R/W

Bit 313029282726252423222120191817161514131211109876543210

Name Reserved Block Length Counter

Bit 313029282726252423222120191817161514131211109876543210

Name Reserved Block Length

Bit 15 14 13 12 11 10 9 8

Name Reserved INCB ADB INCA ADA SWRQ

Reset 0000000

Bit 76543210

Name BPC OT DIR IND TCS EOVR ETC CHEN

Reset 00000000

Bit Description

0CHEN (Channel Enable). Must be set to enable DMA operation on this channel

0: Channel disabled

1: Channel enabled

If CHEN bit in DMACNTLn register is cleared in all channels, the DMA clock is disabled to preserve power.

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1ETC (Enable Interrupt on Terminal Count). Enables a level interrupt, when TC bit is set.

0: Interrupt masked

1: Interrupt enabled

2EOVR (Enable Interrupt on OVR). Enables a level interrupt, when OVR bit is set.

0: Interrupt masked

1: Interrupt enabled

3TCS (Transfer Cycle Size). Speciﬁes the number of bytes transferred in each DMA transfer cycle. In Direct

(Fly-By) mode, undeﬁned results occur if TCS is not equal to the addressed memory bus width.

0: Byte wide transfer

1: Word-wide (16-bit) transfer

4IND (Direct/Indirect Transfer). Transfer Type.

0: Direct (Fly-By)

1: Indirect (Memory-to-Memory)

5DIR (Transfer Direction). Speciﬁes the direction of the transfer relative to Device A.

0: Device A (pointed to by ADCAn) is the source. In Fly-By mode, a read transaction is initialized.

1: Device A (pointed to by ADCAn) is the destination. In Fly-By mode, a write transaction is initialized.

6OT(Operation Type).

0: Single-Buffer mode or Double-Buffer mode enabled

1: Auto-Initialize mode enabled

7BPC (Bus Policy Control). Intermittent (cycle stealing) or continuous (burst).

0: Intermittent operation. DMAC channel n relinquishes the bus after each transaction even if the request is still

asserted.

1: Continous operation. DMAC channel n uses the bus continuously as long as the request is asserted. This mode

can only be used for SW DMA requests (i.e., when SWRQ is set). On HW DMA requests, BPC must be set to 0.

8SWRQ (Software DMA Request).

0: Software DMA request is inactive

1: Software DMA request is active

9ADA (Device A Address Control). Enables Update of Device A Address.

0: ADCAn address unchanged

1: ADCAn address incremented or decremented, according to INCA field

11-10 INCA (Increment/Decrement ADCAn).

Bits

11 10 Description

0 0: Increment ADCAn register by 1

0 1: Increment ADCAn register by 2

1 0: Decrement ADCAn register by 1

1 1: Decrement ADCAn register by 2

12 ADB (Device B Address Control). Enables Update of Device B Address.

0: ADCBn address unchanged

1: ADCBn address incremented or decremented, according to INCB field

14-13 INCB (Increment/Decrement ADCBn).

Bits

14 13 Description

0 0: Increment ADCBn register by 1

0 1: Increment ADCBn register by 2

1 0: Decrement ADCBn register by 1

1 1: Decrement ADCBn register by 2

15 Reserved.

Bit Description

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DMA Status Register (DMASTATn)

A byte-wide, read with write 1 to clear register that holds the status information for the DMAC channel. On reset, the imple-

mented bits are initialized to 0. The reserved bits always return zero when read.

The format of the DMASTATn register is shown below.

Location: Channel 0 - 00 FA1E16

Channel 1 - 00 FA3E16

Channel 2 - 00 FA5E16

Channel 3 - 00 FA7E16

Type: R/W1C

Bit 76543210

Name Reserved VLD CHAC OVR TC

Reset 00000000

Bit Description

0TC1(Terminal Count). When set to 1, indicates that the transfer was completed by a terminal count condition

(BLTCn register reached 0).

1. The VLD, OVR and TC bits are sticky (once set by the occurrence of the speciﬁc condition, they remain set until

explicitly cleared by software). These bits can be cleared individually by writing a value into the DMASTATn reg-

ister with the bit positions to be cleared set to 1; writing 0 to these bits has no effect.

1OVR1(Channel Overrun).

•In double buffered operation (OT bit in DMACNTLn register is 0):

OVR is set to 1 when the present transfer is completed (BLTC = 0), but the parameters for the next transfer

(address and block length) are not valid.

•In auto initialize operation: (OT bit in DMACNTLn register is 1)

OVR is set to 1 when the present transfer is completed (BLTC = 0), but TC bit is still set to 1 (e.g., the software

did not serve the last interrupt).

•In single buffer operation:

This bit is ignored.

2CHAC (Channel Active). Continuously reﬂects the active or inactive status of the channel and is therefore read

only. Data written to CHAC bit is ignored.

0: Indicates that the channel is inactive

1: Indicates that the channel is active (CHEN bit in DMACNTLn register is 1 and BLTC > 0)

3VLD1(Transfer Parameters Valid). Speciﬁes whether the transfer parameters for the next block to be

transferred are valid.

Writing to the BLTRn register sets this bit to 1.

It is cleared to 0 in the following cases:

•The present transfer is completed, and the ADRAn, ADRBn (Indirect mode only) and BLTR registers are copied

to the ADCAn, ADCBn (Indirect mode only) and BLTCn registers, respectively.

•Writing 1 to VLD bit; (writing zero has no effect).

7-4 Reserved.

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4.2.9 Usage Hints

●Do not write to ADCAn, ADCBn or BLTCn and do not change the value of TCS, IND, DIR, OT, ADA, INCA, ADB and

INCB ﬁelds of DMACNTLn register while the associated channel is active (CHAC bit in DMASTATn register is 1).

When initializing these registers, write to BLTCn register last, since writing to BLTCn register activates the channel

immediately (if CHEN bit in DMACNTLn register is set to 1).

●The ADRAn, ADRBn and BLTRn registers store transfer parameters (source address, destination address and block

length) for the next data block to be transferred, for either Auto-Initialize or Double-Buffer modes of operation. When

initializing these registers, write the BLTRn register last, since this validates the next block’s parameters (VLD bit in

DMASTATn register is set to 1).

●The TCS bit in DMACNTLn register is programed according to the bus width of the devices. It determines how many

bytes are transferred in each DMA bus cycle.

●The DMAC does not support non-aligned transfers. The values written to ADCAn, ADRAn, ADCBn and ADRBn must

be multiples of the Transfer Cycle Size (as deﬁned by TCS bit in DMACNTLn register).

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4.3 INTERRUPT CONTROL UNIT (ICU)

The ICU has 31 channels. It interfaces between the different modules’ interrupt requests and external interrupt requests and

also generates the core interrupt. It generates both maskable and non-maskable interrupts. The ICU has a predetermined

scheme that allocates priority.

4.3.1 Features

Non-Maskable Interrupts (NMI)

●Gathers all edge-triggered non-maskable interrupt sources

—External Power Fail (PFAIL) interrupt source

●Holds the status of the current pending NMI requests

●Generates non-maskable interrupt (NMI) to the core

Maskable Interrupts

●31 active high-level or edge-triggered interrupt sources

●Core vectored interrupt mode

●Fixed priority among interrupt sources

●Individual enable/disable for each interrupt source

●Polling support by an interrupt status register

●Clear registers for edge-triggered interrupts

4.3.2 Non-Maskable Interrupt (NMI)

The Interrupt Control Unit (ICU) gathers external non-maskable interrupt (NMI) sources and generates an NMI interrupt to

the core when required.

External NMI Inputs

The ICU processes the PFAIL signal to send to the CR16B NMI input.

Non-Maskable Interrupt Processing

The CR16B core performs an “Interrupt Acknowledge” bus cycle when beginning to process a non-maskable interrupt. The

address associated with this core bus cycle is within the internal core address space and may be monitored as a Core Bus

Monitoring (CBM) clock cycle. For additional details, see “Core Bus Monitoring” on page 82 and Section 4.20.6 on page 273.

After reset, NMI is disabled and must remain disabled until the software initializes the interrupt table, interrupt base and the

interrupt mode.

The PFAIL interrupt is enabled by setting ENLCK bit and remains enabled until a reset occurs. This allows the external NMI

feature to be enabled only after the Interrupt Base Register (IMASK) and the Interrupt Stack Pointer (ISP), in the core, have

been set up.

Alternatively, the external PFAIL interrupt can be enabled by setting EN bit, which remains enabled until an interrupt event

or a reset occurs. The NMISTAT register holds the status of the current pending NMI request. When the bit in NMISTAT is

set to 1, an NMI request to the core is issued. NMISTAT is cleared each time its contents are read. NMI handlers must read

the NMISTAT register to allow new NMI events to occur.

Note that PFAIL status bit in NMISTAT register may be set as a result of transient enable conditions on PFAIL. To avoid an

interrupt to the core, after configuring the PFAIL input for operation, read the NMISTAT register and then enable PFAIL by

writing 1 to EN bit in PFAIL register.

PFAIL Input

The PFAIL signal is an asynchronous input with Schmitt trigger characteristics and an internal synchronization circuit; there-

fore, no external synchronizing circuit is needed. The PFAIL signal generates an interrupt on its falling edge.

4.3.3 Maskable Interrupts

The ICU receives level or edge-triggered interrupt request signals from 31 sources and generates a vectored interrupt to the

CR16B core when required. Priority among the interrupt sources (named INT1 to INT31) is fixed. Each interrupt source can

be individually enabled or disabled under software control through:

●ICU interrupt enable registers

●Interrupt enable bits in the peripherals that request the interrupts.

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Pending interrupts, enabled or disabled, can be polled using the Status registers. The CR16B core supports INT0, but the

ICU reserves INT0 so that it is not connected to any interrupt source.

Maskable Interrupt Vectors

Interrupt vector numbers are always positive and are in the range 1016 to 2F16. The IVCT register contains the interrupt vec-

tor of the enabled and pending interrupt with the highest priority. The interrupt vector 1016 corresponds to INT0 with the low-

est priority; the vector 2F16 corresponds to INT31 with the highest priority.

The CR16B core performs an “Interrupt Acknowledge” bus cycle on receiving an enabled maskable interrupt request from

the ICU. During the interrupt acknowledge cycle, a byte is read from address 00 FE0016 (IVCT register). The byte read is

used as an index in the Dispatch Table to determine the address of the interrupt handler.

Although INT0 is not connected to any interrupt source, the IVCT register can return the value 1016. This happens, for ex-

ample, when the interrupt request is removed before the interrupt acknowledge cycle. The entry in the Dispatch Table should

point to a default interrupt handler that handles this error condition.

Pending Interrupts

Edge-triggered interrupts are latched by the Interrupt Status register. A pending edge-triggered interrupt is cleared by writing

a ‘1’ to the respective bit in the Edge Interrupt Clear register, IECLR0 or IECLR1.

A pending level-triggered interrupt is cleared when the interrupt source is not active; note that the interrupt should be cleared

at the device/module that drives it by clearing the event status bit.

Interrupt mask bits (IENAM register bits) and pending interrupt bits (ISTAT register bits), should be cleared to 0 only when

interrupts are disabled; i.e., when bits I and/or E in PSR register (a core register) are 0. Bits in IENAM may be set at any time.

Interrupt Priorities

The priorities of the maskable interrupts are hard-wired and thus fixed. The interrupts are named INT0 to INT31, where INT0

has the lowest priority and INT31 has the highest priority.

Power-Down Modes

Interrupt sources that may generate unexpected interrupts in Idle mode should be masked before switching to the power-

down mode.

External Interrupt Inputs

When an MIWU input is disabled, and the respective WKOxx output at the MIWU is connected to the ICU, the MIWU input

is fed directly to the ICU. In this case, the interrupt inputs are asynchronous. They are recognized by the PC87591x during

cycles in which the input setup and hold time requirements are satisfied. To use an external interrupt which is shared with

an I/O port, configure the I/O port to its alternate function (see Section 2.4 on page 54).

Interrupt Assignment

Table 16 shows the mapping of the ICU maskable interrupts to different functions. For information on mask bits and the clear

mechanism for the status bit in internal level interrupts, refer to descriptions of the module that is the interrupt source.

Table 16. ICU Interrupt Assignments

INT

Number Source Type Details Priority

INT0 - - Error condition occurred (spurious interrupt) Lowest

INT1 External/MIWU Level-High External Interrupt EXWINT20 through the MIWU1

INT2 Internal Level-High Host I/F Keyboard/Mouse channel Output Buffer Empty

INT3 Internal Level-High Host I/F Power Management channel 1 or channel 2 Output

Buffer Empty

INT4 Internal Level-High High-Frequency Clock Generator

INT5 Internal Level-High MIWU PSWUINT or WKINTD

INT6 External/MIWU Level-High External Interrupt EXWINT23 through the MIWU1

INT7 Internal Level-High MFT16 1 Interrupt (INT1 ORed with INT2)

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INT8 Internal Level-High ADC interrupt (ADCI)

INT9 Internal Level-High ACCESS.bus 1 interrupt

INT10 Internal Level-High ACCESS.bus 2 interrupt

INT11 MIWU Level-High Internal Keyboard Scan Interrupt (KBSINT from MIWU) or

ACM Interrupt

INT12 Internal/MIWU Level-High MSWC interrupt through the MIWU

INT13 Internal/MIWU Edge Rising TWM system tick (T0OUT), through the MIWU2

INT14 External/MIWU Level-High SWIN input1, through the MIWU

INT15 Reserved

INT16 Internal Level-High USART Interrupt (TX Int OR RX int)

INT17 External/MIWU Level-High External Interrupt EXWINT24 through the MIWU1

INT18 Internal Edge Falling PS/2 shift mechanism (PSINT3)

INT19 Internal Edge Falling PS/2 shift mechanism (PSINT2)

INT20 Internal Level High /

Edge Falling3PS/2 shift mechanism (PSINT1)

INT21 External/MIWU Level-High External Interrupt EXWINT22 through the MIWU1

INT22 Internal Level-High MFT16 2 Interrupt (INT1 ORed with INT2)

INT23 Internal Level-High Flash I/F interrupt or

Shared Memory Interrupt

INT24 Internal Level-High Host I/F Keyboard/Mouse channel Input Buffer Full

INT25 Internal Level-High Host I/F Power Management channel 1 or channel 2 Input

Buffer Full

INT26 Reserved

INT27 Internal Level-High DMA Channel 0

INT28 Internal Level-High DMA Channel 1

INT29 Reserved

INT30 Reserved

INT31 External/MIWU Level-High External Interrupt EXWINT21 through the MIWU1Highest

1. To enable the external interrupt, set the pin to its alternate function. When used as I/O port signals the External

interrupt input is forced to 0

2. When in Active mode, it is advised to disable the T0OUT channel of the MIWU, this saves the need to clear the

pending bit in the MIWU on each interrupt.

3. Falling Edge is enabled for this input when the PS/2 channel ‘Disabled Shift Mechanism Interrupts’ are enabled

(DSMIE in PSIEN register = 1)

Table 16. ICU Interrupt Assignments (Continued)

INT

Number Source Type Details Priority

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4.3.4 ICU Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

ICU Register Map

Interrupt Vector Register (IVCT)

The IVCT register holds the vector number of the interrupt vector. IVCT is set to 1016 on reset.

Location: 00 FE0016

Type: RO

NMI Status Register (NMISTAT)

The NMISTAT register holds the status of the current pending Non-Maskable Interrupt (NMI) requests. This register is cleared

on reset and each time its contents are read. Refer to the description of the PFAIL register below for additional details.

Location: 00 FE0216

Type: RO

Mnemonic Register Name Type

IVCT Interrupt Vector RO

NMISTAT NMI Status RO

PFAIL Power Fail Interrupt Control and Status R/W

ISTAT0 Interrupt Status 0 RO

ISTAT1 Interrupt Status 1 RO

IENAM0 Interrupt Enable and Mask 0 R/W

IENAM1 Interrupt Enable and Mask 1 R/W

IECLR0 Edge Interrupt Clear 0 WO

IECLR1 Edge Interrupt Clear 1 WO

Bit 76543210

Name 0 0 INTVECT

Reset 00010000

Bit Description

5-0 INTVECT (Interrupt Vector). Contains the encoded value of the enabled pending interrupt with the highest

priority; the valid values range from 1016 to 2F16. Valid during an interrupt acknowledge core bus cycle in which

IVCT is read. It may contain invalid data when INTVECT is updated.

7-6 These bits return 0 when read.

Bit 76543210

Name Reserved EXT

Reset 00000000

Bit Description

0EXT (External Non-Maskable Interrupt Request).

0: No external non-maskable interrupt request occurred

1: External non-maskable interrupt request occurred

7-1 Reserved.

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Power Fail Interrupt Control and Status Register (PFAIL)

The PFAIL register holds the current value of the PFAIL signal and controls the NMI interrupt generation based on a falling

edge of the PFAIL signal. EN and ENLCK are cleared on reset. When writing to this register, all reserved bits must be written

with 0 for the device to function properly.

Location: 00 FE0416

Type: R/W

Interrupt Status Register 0 (ISTAT0)

This register indicates which maskable interrupts are pending regardless of the state of the corresponding IENA bits. ISTAT0

is cleared on reset.

Location: 00 FE0A16

Type: RO

Bit 76543210

Name Reserved ENLCK PIN EN

Reset xxxx00x0

Bit Description

0EN (PFAIL Interrupt Enable). An NMI interrupt is generated when this bit is set to 1 and the PFAIL signal

changes its value from high to low. The bit is cleared by hardware on reset and whenever the interrupt occurs

(i.e., when EXT bit in NMISTAT register is set). It can be set and cleared by software; however, software can set

this bit only when EXT is cleared. This bit is ignored when ENLCK is set.

0: No NMI interrupt generated

1: NMI interrupt generated

1PIN (PFAILPin Value). Contains the current (non-inverted) PFAIL signal value. This bit is read only; data written to

it is ignored.

2ENLCK PFAIL Interrupt Enable Lock. When this bit is set to 1, the external PFAIL feature is enabled and

locked; it cannot be cleared by software and can only be cleared by hardware on reset. After setting this bit, an

NMI interrupt is generated every time the PFAIL signal changes its value from high to low. Note that when

ENLCK is set, EN bit is ignored.

0: External PFAIL feature disabled

1: External PFAIL feature enabled and locked

7-3 Reserved.

Bit 1514131211109876543210

Name IST15-0

Reset 0 000000000000000

Bit Description

15-0 IST15-0 (Interrupt Status). Each bit indicates if an interrupt event was sent to the ICU; IST15 to IST0

correspond to INT15 to INT0, respectively. Since INT0 is not used, IST0 always reads 0. Each bit is encoded

as follows:

0: Interrupt input to ICU not pending

1: Interrupt input to ICU pending

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Interrupt Status Register 1 (ISTAT1)

This register indicates which maskable interrupts are pending regardless of the state of the corresponding IENA bits.

Location: 00 FE0C16

Type: RO

Interrupt Enable and Mask Register 0 (IENAM0)

This register controls the enable/disable of the maskable interrupt sources INT0 to INT15. The register is cleared (000016)

on reset.

Location: 00 FE0E16

Type: R/W

Interrupt Enable and Mask Register 1 (IENAM1)

This register controls the enable/disable of the maskable interrupt sources INT16 to INT31. The register is cleared (000016)

on reset.

Location: 00 FE1016

Type: R/W

Bit 1514131211109876543210

Name IST31-16

Reset 0 000000000000000

Bit Description

15-0 IST31-16 (Interrupt Status). Each bit indicates if an interrupt event was sent to the ICU; IST31 to IST16

correspond to INT31 to INT16, respectively. Each bit is encoded as follows:

0: Interrupt input to ICU not pending

1: Interrupt input to ICU pending

Bit 1514131211109876543210

Name IENA15-0

Reset 0 000000000000000

Bit Description

15-0 IENA15-0 (Interrupt Enable). Each bit enables or disables the corresponding interrupt request INT0 to INT15;

e.g. IENA15 controls INT15. Since INT0 is not used, IENA0 has no effect on the operation of the ICU.

0: Interrupt disabled

1: Interrupt enabled

Bit 1514131211109876543210

Name IENA31-16

Reset 0 000000000000000

Bit Description

15-0 IENA31-16 (Interrupt Enable). Each bit enables or disables the corresponding interrupt request INT16 to

INT31; e.g. IENA16 controls INT16.

0: Interrupt disabled

1: Interrupt enabled

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Edge Interrupt Clear Register 0 (IECLR0)

The IECLR register is used to clear pending, edge-triggered interrupts.

Location: 00 FE1216

Type: WO

Edge Interrupt Clear Register 1 (IECLR1)

The IECLR register is used to clear pending, edge-triggered interrupts.

Location: 00 FE1416

Type: WO

4.3.5 Usage Hints

Initializing

The recommended initialization sequence is:

1. Initialize both the INTBASE register and the interrupt stack pointer of the core.

2. Prepare the interrupt routines of the interrupts used.

3. Clear edge interrupt used.

4. Set relevant bits of the peripherals.

5. Set relevant bits in IENAM register.

6. Set PFAIL register.

7. Enable core interrupt.

Clearing

Clearing an interrupt request before it is serviced may cause a spurious interrupt (i.e., when the core detects an interrupt not

reflected by IVCT). Clear interrupt requests only when interrupts are disabled. Clear IENAM bits and ISTAT bits while the

core interrupts are disabled (i.e., bits I and/or E in PSR register are cleared).

Nesting

The IENAM registers can be used in interrupt handlers to allow interrupt nesting. When the core acknowledges an interrupt, it

disables maskable interrupts by clearing bit I in PSR register and executes the interrupt service routine. This routine can enable

nested interrupts by setting bit I in PSR register and can use the IENAM registers to control which interrupts are allowed.

Bit 1514131211109876543210

Name IEC15-1 Res.

Bit Description

0Reserved.

15-1 IEC15-1 (Edge Interrupt Clear). Each bit clears the corresponding bit in ISTAT0 register. Writing to the bit

positions of level-triggered interrupts has no effect. Read always returns FFFF16. IEC15 to IEC1 correspond to

INT15 to INT1, respectively. Each bit is encoded as follows:

0: No effect

1: Pending edge-triggered interrupt cleared

Bit 1514131211109876543210

Name IEC31-16

Bit Description

15-0 IEC31-16 (Edge Interrupt Clear). Each bit clears the corresponding bit in ISTAT1 register. Writing to the bit

positions of level-triggered interrupts has no effect. Read always returns FFFF16. IEC31 to IEC16 correspond to

INT31 to INT16, respectively. Each bit is encoded as follows:

0: No effect

1: Pending edge-triggered interrupt cleared

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4.4 MULTI-INPUT WAKE-UP (MIWU)

The Multi-Input Wake-Up Unit (MIWU) allows the PC87591x to exit Idle mode. In addition, it provides signal conditioning and

grouping of external interrupt sources. It supports a total of 32 internal and/or external wake-up sources.

4.4.1 Features

●Supports up to 32 internal and/or external wake-up inputs

●Generates a wake-up signal

●Generates interrupt signals for:

—each of the 32 inputs

—one interrupt for each group of eight inputs e.g., I/O ports

●User-selectable trigger condition on each input:

—positive edge

—negative edge

●Individual enable and pending bits for each input

●Programmable bypass mode connects inputs to ICU without MIWU involvement

4.4.2 Operation

Overview

The Multi-Input Wake-Up Unit (MIWU) detects a valid software-selectable trigger condition on any of its inputs. On detection

of a valid trigger condition, the MIWU generates a wake-up request and/or an interrupt request. The wake-up request is con-

nected to the Power Management module (PMC) and may be utilized to exit the Idle mode and return to Active mode. The

interrupt requests are used to signal to the Interrupt Control Unit (ICU) that either an edge-triggered external or internal in-

terrupt condition has occurred. Figure 32 shows a block diagram of the Multi-Input Wake-Up module.

Note that the MIWU module is active while in Idle mode. Note, however, that because all device clocks are stopped in Idle

mode, the detection of a trigger condition on an input, and the resulting set of the pending flag, are not synchronous to the

system clock.

Table 17 lists the MIWU sources and interrupts used in the PC87591x.

Table 17. Input Assignments

Source Destination

Name MIWU Input Interrupt Name MIWU Output

PSCLK1 WUI10 PSWUINT WKINTA

PSCLK2 WUI11

PSCLK3 WUI12

PSDAT1 WUI13

PSDAT2 WUI14

PSDAT3 WUI15

PSCLK4 WUI16

PSDAT4 WUI17

EWXINT20 WUI20 INT1 WKO20

EXWINT21 WUI21 INT31 WKO21

EXWINT22 WUI22 INT21 WKO22

EXWINT23 WUI23 INT6 WKO23

EXWINT24 WUI24 INT17 WKO24

SWIN WUI25 INT14 WKO25

MSWC Wake-Up WUI26 INT12 WKO26

T0OUT1WUI27 T0OUTINT WKO27

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KBSIN0 WUI30 KBSINT WKINTC

KBSIN1 WUI31

KBSIN2 WUI32

KBSIN3 WUI33

KBSIN4 WUI34

KBSIN5 WUI35

KBSIN6 WUI36

KBSIN7 WUI37

EXWINT40 WUI40 MIWU2 WKINTD

Reserved WUI41

Host Access Wake-Up2WUI42

ACCESS.bus 1 Wake-Up1WUI43

ACCESS.bus 2 Wake-Up1WUI44

EXWINT45 WUI45

EXWINT46 WUI46

Analog Comparators (ACMI) WUI47

1. Program the input to detect the rising edge of the input event.

2. The wake-up input is triggered by a host access to one of a selected set of

devices in the PC87591x. See “Core Interrupt” on page 343. Conﬁgure the

WUI26 for rising edge detection.

Table 17. Input Assignments (Continued)

Source Destination

Name MIWU Input Interrupt Name MIWU Output

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Trigger Conditions

Through the WKEDGx registers, the trigger condition on the selected input signal can be selected as either positive edge

(low-to-high transition) or negative edge (high-to-low transition).

Peripheral Bus

WKEN1

..........................

WUI30

Wake-Up Signal to

Power Management

WKINTA

WUI20

WUI27

WUI10

WUI17

WKEDG1 WKPND1 1

SEL

WKO10

WKO17

...

Interrupt

Control

Unit

Power

Management

WKUP Inputs Group 1

WKUP Inputs Group 3

(Uses registers WKEDG3, WKPND3 and WKEN3)

WUI37 WKO30

WKO37

WKINTC

WUI40

WKUP Inputs Group 4

(Uses registers WKEDG4, WKPND4 and WKEN4)

WUI47 WKO40

WKO47

WKINTD

Figure 32. Multi-Input Wake-Up Block Diagram

WKUP Inputs Group 3

(Uses registers WKEDG2, WKPND2 and WKEN2)

WKO20

WKO27

WKINTB

(ICU)

Module

Note: Not all MIWU-ICU connections are implemented; for details,

see ICU interrupt assignments in Table 17 on page 105.

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Pending Flags

An occurrence of a trigger condition for the Multi-Input Wake-Up input is latched into the respective pending bit in WKPNDx

signal.

Since the WKPNDx register holds a pending wake-up condition until it is cleared, the device does not enter the IDLE mode

if any wake-up bit is both enabled and pending. Consequently, the pending flags must be cleared before an attempt to enter

the Idle mode.

Input Enable

The MIWU utilizes multiple Multi-input Wake-Up signals. Setting the appropriate bits in the WKENAx registers select which

particular wake-up signal causes the device to exit Idle mode.

Interrupts

The combined output of all pending and enabled channels of the MIWU module generates the wake-up signal, which is fed

into both the Power Management Control module (PMC) and the Interrupt Control Unit (ICU). Therefore, each wake-up of

the device can be followed by a wake-up interrupt. Since the device can not enter the power reduction mode without having

the core execute a “WAIT” instruction, a wake-up interrupt is needed to terminate the “WAIT” instruction on wake-up.

MIWU outputs WKO10 through WKO37 may be connected to the Interrupt Control Unit (ICU) to generate an interrupt asso-

ciated with the specific MIWU output. The WKOxx behaves as follows:

●When the respective WKENxx bit is cleared, the WUIxx is connected to the ICU directly (bypassing the edge detec-

tors and pending bits). The ICU can be conﬁgured to use the signal as a level or edge triggered interrupt.

●When the respective WKENxx bit is enabled, the output of the pending bit, WKPDxx, is connected to WKOxx.

Note: To enable and disable ICU interrupts generated by their associated WKOxx output of the MIWU, use the ICU mask

In addition, the MIWU provides four interrupt request lines: WKINTA, WKINTB, WKINTC and WKINTD (see Figure 32 on

page 107). These are routed to the ICU (except WKINTB) and can request an interrupt if a valid trigger condition occurred

on any of the enabled input sources within the group of eight inputs associated with the interrupt line. For a detailed summary

of the interrupts available, see Table 17 on page 105.

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4.4.3 MIWU Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

MIWU Register Map

Edge Detection Register (WKEDG1)

Byte-wide read/write register that configures the trigger condition of the input signals WUI10 to WUI17. The register is

cleared on reset. This configures all associated input signals to be triggered on a rising edge.

Location: 00 FFC016

Type: R/W

Mnemonic Register Name Type

WKEDG1 Edge Detection Register R/W

WKEDG2 Edge Detection Register R/W

WKEDG3 Edge Detection Register R/W

WKEDG4 Edge Detection Register R/W

WKPND1 Pending Register R/W

WKPND2 Pending Register R/W

WKPND3 Pending Register R/W

WKPND4 Pending Register R/W

WKEN1 Enable Register R/W

WKEN2 Enable Register R/W

WKEN3 Enable Register R/W

WKEN4 Enable Register R/W

WKPCL1 Pending Clear Register WO

WKPCL2 Pending Clear Register WO

WKPCL3 Pending Clear Register WO

WKPCL4 Pending Clear Register WO

Bit 76543210

Name WKED17-WKED10

Reset 00000000

Bit Description

7-0 Edge Selection. For inputs WUI10 through WUI17. Each bit is associated with one of eight inputs.

0: Low-to-High transition.

1: High-to-Low transition.

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Edge Detection Register (WKEDG2)

Byte-wide read/write register that configures the trigger condition of the input signals WUI20 to WUI27. The functionality of

the register is identical to the WKEDG1 register described above.

Location: 00 FFC216

Type: R/W

Edge Detection Register (WKEDG3)

Byte-wide read/write register that configures the trigger condition of the input signals WUI30 to WUI37. The functionality of

the register is identical to the WKEDG1 register described above.

Location: 00 FFC416

Type: R/W

Edge Detection Register (WKEDG4)

Byte-wide read/write register that configures the trigger condition of the input signals WUI40 to WUI47. The functionality of

the register is identical to the WKEDG1 register described above.

Location: 00 FFC616

Type: R/W

Pending Register (WKPND1)

Byte-wide read/write register that latches the occurrence of a selected trigger condition associated with the input signals

WUI10 to WUI17. On reset, the WKPND1 register is cleared (0). This indicates that no occurrence of the selected trigger

condition is pending.

Note: Only software can set the register bits; only the WKPCL1 register can clear them. Writing a 0 to any of the bits leaves

their values unchanged. The WKPND1 register format is shown below:

Location: 00 FFC816

Type: R/W

Pending Register (WKPND2)

Byte-wide read/write register that latches the occurrence of a selected trigger condition associated with the input signals

WUI20 to WUI27. For a detailed description of the register see the above description of the WKPND1 register.

Location: 00 FFCC16

Type: R/W

Pending Register (WKPND3)

Byte-wide read/write register that latches the occurrence of a selected trigger condition associated with the input signals

WUI30 to WUI37. For a detailed description of the register see the above description of the WKPND1 register.

Location: 00 FFD016

Type: R/W

Bit 76543210

Name WKPD17-WKPD10

Reset 00000000

Bit Description

7-0 Wake-Up Pending. If set, (1) indicates that a valid trigger condition occurred on the associated input.

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Pending Register (WKPND4)

Byte-wide read/write register that latches the occurrence of a selected trigger condition associated with the input signals

WUI40 to WUI47. For a detailed description of the register see the above description of the WKPND1 register.

Location: 00 FFD416

Type: R/W

Enable Register (WKEN1)

Byte-wide read/write register that enables the wake-up function of the associated input signal, WUI10 to WUI17. On reset,

WDENA1 is cleared (0); this disables the associated input signals. The WKENA1 register format is shown below:

Location: 00 FFD816

Type: R/W

Enable Register (WKEN2)

Byte-wide read/write register that enables the wake-up function of the associated input signal, WUI20 to WUI27. For a de-

tailed description of the register, see the above description of the WKEN1 register.

Location: 00 FFDA16

Type: R/W

Enable Register (WKEN3)

Byte-wide read/write register that enables the wake-up function of the associated input signal, WUI30 to WUI37. For a de-

tailed description of the register, see the above description of the WKEN1 register.

Location: 00 FFDC16

Type: R/W

Enable Register (WKEN4)

Byte-wide read/write register that enables the wake-up function of the associated input signal, WUI40 to WUI47. For a de-

tailed description of the register, see the above description of the WKEN1 register.

Location: 00 FFDE16

Type: R/W

Pending Clear Register (WKPCL1)

Byte-wide write-only register that controls the clearing (0) of the pending bits associated with the WUI10 through WUI17 in-

puts. This avoids potential hardware/software collisions during read-modify-write operations. The WKPCL1 register format

is shown below:

Location: 00 FFCA16

Type: WO

Bit 76543210

Name WKEN17-WKEN10

Reset 00000000

Bit Description

7-0 Wake-Up Enable. If set (1), a valid trigger condition on the associated input generates a wake-up signal or

EXTINTx interrupt request

Bit 76543210

Name WKCL17-WKCL10

Bit Description

7-0 Clear Pending Flag. If a 1 is written to any bit, the associated pending ﬂag located in WKPND1 is cleared (0).

Writing a 0 to any bit leaves the value of the corresponding pending ﬂag unchanged.

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Pending Clear Register (WKPCL2)

Controls the clearing (0) of the pending bits associated with the WUI20 through WUI27 inputs. For a detailed description of

the register see, the above description of the WKPCL1 register.

Location: 00 FFCE16

Type: WO

Pending Clear Register (WKPCL3)

Controls the clearing (0) of the pending bits associated with the WUI30 through WUI37 inputs. For a detailed description of

the register, see the above description of the WKPCL1 register.

Location: 00 FFD216

Type: WO

Pending Clear Register (WKPCL4)

Controls the clearing (0) of the pending bits associated with the WUI40 through WUI47 inputs. For a detailed description of

the register, see the above description of the WKPCL1 register.

Location: 00 FFD616

Type: WO

4.4.4 Usage Hints

1. When changing an edge select, perform the following steps to avoid a spurious wake-up condition, which may occur as

a result of the edge change:

a. Clear the associated WKENxx bit.

b. Select the required the edge in the WKEDGx register.

c. Clear the associated WKPDxx bit.

d. Re-enable the associated WKENxx bit.

2. The correct use of the Multi-Input Wake-Up circuit, which avoids false triggering of a wake-up condition, requires the

following sequence of actions. Use the same procedure following a Reset since the wake-up inputs are left floating, pro-

ducing unknown data on the MIWU input signals.

a. If the input originates from an I/O port, write to the port alternate function and, if required, direction register to set the

pin to interrupt inputs.

b. Clear the WKENAx register or, if a WKOxx interrupt is used, disable the interrupt via the ICU.

c. Write the WKEDGx register to select the desired type of edge sensitivity for each of the pins used.

d. Clear the WKPNDx register to cancel any pending bits.

e. Eithersetthe WKENxx bits associated with the pins to be used, thus enabling them for the wake-up/interrupt function,

or re-enable the interrupt via the ICU.

3. On Reset, the WKEDGx registers are configured to select positive edge sensitivity for all wake-up inputs. To change the

edge sensitivity of an input signal while preventing the false triggering of a wake-up/interrupt condition, use the following

procedure.

a. Clear the WKENxx bit associated with the WUIxx input to disable that input.

b. Write to the WKEDGx register to select the new type of edge sensitivity for the specific input.

c. Clear the WKPDxx bit associated with the WUIxx input.

d. Set the WKENxx bit associated with the WUIxx input to re-enable it.

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4.5 GENERAL-PURPOSE I/O (GPIO) PORTS

The PC87591x includes four types of General-Purpose I/O (GPIO) ports: Px, Py, Pz and Pw.

●Px signals: Each signal is bidirectional and can be conﬁgured as input or output. An internal weak pull-up is provided

to hold the pin high when used as an input or in an open-drain scheme.

●Py signals: Each signal is input only. An internal weak pull-up is provided to hold the pin high.

●Pz signals: Each signal is output only. It may be conﬁgured to work as totem-pole or in an open-drain scheme.

●Pw signals: Each signal is bidirectional and can be conﬁgured for input or output. The Pw pins may be shared with

development system functions. These ports can be implemented off-chip in DEV environment using external logic.

The GPIO signals are organized in ports. Each port is either 8-bits or 16-bits wide. In ports where not all eight bits are used,

some of the register’s bits are reserved. Some GPIO signals share their pins with one or more alternate functions. A config-

uration bit selects which function is active (see Section 2.4 on page 54).

Note: Some GPIO signals are only available in a 176-pin package.

GPIO Port Functionality

The PC87591x provides 117 GPIO pins in the 176-pin package and 84 GPIO pins in the 128-pin package. They are subdi-

vided into the following groups:

●Ports IOPA(7-0), IOPB(7-0), IOPC(7-0), IOPD(7-0) and IOPF(7-0)

These ports are on-chip, General-Purpose Input/Output (GPIO) ports (type Px).

IOPC0 is reserved for power supply control use. Bit 0 of PCALT, PCDIR, PCWPU and PCDOUT are reset on VCC Power-

Up reset and WATCHDOG reset only.

PB5 and PB6 have an option for automatic TRI-STATE based on LPCPD. See “MSWC Control Status Register 3

(MSWCTL3)” on page 330 for the enable function.

PB6 is selected to its alternate function, by default (i.e., bit 6 is set to 1).

Ports IOPA4-0, IOPB2-0, IOPC0 and IOPD3 have the option to echo the value of the associated input. For the exact

echo matrix specifications, see Section 2.4.3 on page 59.

Bit 5 of PBALT register, bit 0 of PCALT register and bits 4-7 of PDALT register are read only (RO) and return a value of

zero.

●IOPE(7-0) and KBSIN(7-0)

These are General-Purpose Input (GPI) ports (type Py). IOPE(3-0) and IOPE5 do not implement the pull-up function,

and the respective bits in PEWPU are reserved. KBSIN has no alternate function; thus it has no PyALT register.

●KBSOUT(15-0)

This is a 16-bit General-Purpose Output (GPO) port (type Pz). Since KBSOUT has no alternate functions, its alter-

nate function register is not implemented. The reset value of KBSOUT register is FFFF16. KBSOUT has open-drain

output drivers.

●Ports IOPH(7-0), IOPI(7-0), IOPJ(7-0), IOPK(7-0),IOPL(4-0) and IOPM(7-0)

These ports are on-chip, General-Purpose Input/Output (GPIO) ports (type Pw).

●When the analog function is enable, the Read function, for GPIO signals that are multiplexed with analog functions,

is disabled; this affects signals KBSIN(7-0) and IOPE(3-0).

When the BIU function is enabled, the Read function, for GPIO signals that are multiplexed with BIU signals, is dis-

abled; this affects signals PH(7-0), PI(7-0), PJ(1-0), PK(7-0), PL(7-0) and PM(7-0).

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4.5.1 Features

●General-Purpose Input/Output (GPIO) Port (Px).

—Each pin functions as input or output signal.

—Direction register controls the port direction.

—Weak pull-up.

—Read-back on all registers.

●General-Purpose Input (GPI) Port (Py).

—All port pins function as input signals.

—Weak pull-up.

—Read-back on all control registers.

●General-Purpose Output (GPO) Port (Pz).

—All pins function as output signals.

—Read-back on all registers.

●General-Purpose Input/Output (GPIO) Port (Pw).

—DEV environment support.

—Pins shared with DEV environment signals.

—Off-chip implementation supported in DEV environments.

—Binary and cycle-by-cycle compatibility between environments.

—Each pin functions as input or output signal.

—Direction register controls the port direction.

—Read-back on all registers.

●Each I/O pin can be conﬁgured as a GPIO port or as an alternate function.

—Some I/O or input pins can provide interrupt functions.

4.5.2 GPIO Port Px

Bidirectional Port with Alternate Function

The GPIO port enables access to input and output pins. It also controls the pin usage either as an I/O port or in its alternate

function. Figure 33 illustrates this functionality.

Direction

Data Output {

Direction

Weak Pull-Up

Data Input Register

MUX1

MUX2

Data Out

Alt Device Data

Alt

Alt Device Direction

Alt

Alt Device Data Input

Data Input Read

Pull-Up

Weak Pull-Up

MUX3

Alternate

Function {

(PxWPU)

(PxDIR)

(PxDOUT)

PxDIN

Alt

Figure 33. GPIO Port Px Schematic Diagram

{

Output

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Output Buffer

The output buffer is a TRI-STATE buffer. The output type (i.e., CMOS or TTL) and its driving capabilities are described in

Section 2.2 on page 41.

Input Buffer

The I/O port input buffer characteristics are defined in Section 2.2 on page 41.

The input buffer has an enable input. When enabled, the buffer inputs the pin’s logic level to the on-chip modules. When

disabled, the input is blocked to prevent supply leakage currents.

Weak Pull-Up

The weak pull-up is enabled when the corresponding bit of PxWPU is set (1) and the pin is configured as an input port. When

the pin is configured for input, this pull-up can prevent the input from being in an undefined state. When the pin is configured

as an output port, this pull-up is disabled.

Alternate Function

The PxALT controls the use of each of the port pins for GPIO or for the pin’s respective alternate function.

When PxALT bit is cleared (0):

●The corresponding pin is used as a GPIO pin.

●The output buffer is controlled by the Direction and Data Output registers.

●The input buffer is routed to the Data Input register.

In this case, the input buffer is blocked, except when the buffer is actually being read.

●The pull-up is enabled when both the PxWPU is set and the device puts the output buffer in TRI-STATE.

When a bit in PxALT is set (1):

●The corresponding pin is used for an alternate function (i.e., a signal from/to some other PC87591x module).

●The output buffer data and TRI-STATE are controlled by signals from the alternate module.

●The input buffer is always enabled when the alternate function is an input; therefore, to minimize current consump-

tion, the signal should be held above VCC−0.2 or below GND+0.2V.

●The pull-up is enabled when PxWPU is set and the device puts the output buffer in TRI-STATE.

Port Direction

The Port Direction register (PxDIR) controls the direction of the port. If set (1), each bit in the register causes the correspond-

ing port signal to serve as an output port, thus enabling the output buffer.

When cleared, the port serves as an input port signal, thus putting the output buffer in TRI-STATE.

If the corresponding bit in PxWPU is set, it also enables the pull-up.

Data Output

The Data Output (PxDOUT) register holds the data to be driven onto the pin, when the respective pin is configured as GPIO

and its direction is set as output.

Data Input

The Data Input (PxDIN) register returns the current value/state of the pin. This register can always be read.

Open Drain

To use the GPIO pin as an inverting open-drain output buffer, the software should clear the corresponding bit in PxDOUT

When the signal direction is set as output (1), a value of 0 is forced. When the direction is set for input (0), the signal is in

TRI-STATE and is not forced low.

The internal weak pull-up can pull the signal high when it is not forced low, by writing (1) to the corresponding bit of PxWPU.

Input Echo Function

SomeofthePxpinscanecho the value of an input pin. Figure 34 illustrates the modified structure of Px port pins that support

the echo function. The input echo function may be used when the Px pin is configured to operate as a General-Purpose

output pin.

Table 9 on page 60 defines pairs of input ports (Pi) and output ports (Po) and the Echo Enable bit associated with each pair.

When the pair’s Echo Enable bit is set, and if Po is configured as output, the value from the input bit (Pi) is output to the

respective output port (Po). When the pair’s Echo Enable bit is cleared, and if Po is configured as output, the value in

PxDOUT is output to the respective output port.

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4.5.3 GPI Port Py

Input Only Port with Alternate Function

The General-Purpose Input (GPI) port (Py) contains a subset of the GPIO functions. It can be used as a GPI port or as an

input signal for an alternate function. Figure 35 illustrates its functionality.

MUX1

MUX2

Alt

Pull-Up

MUX3

PxAlt

(PxWPU)

(PxDIR)

(PxDOUT)

PxDIN

Alt

Figure 34. GPIO Port Px Output with Echo Schematic Diagram

MUX4

Echo EN

To MIWU

Data Out

Direction Register {

Weak Pull-Up Register

Data In Register

Alt Device Direction

Alt Device Data Input

Data In Read

Alternative Function Register

{

or Py

{

Data Input Register

MUX3

Alt

Alt Device Data Input

Data Input Read

Weak Pull-Up

Pull-Up

PyAlt

Alternate Function Register

Weak Pull-Up

(PyWPU)

Alt

PyDIN

Figure 35. GPI Port Py Schematic Diagram

{

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Input Buffer

The input buffer characteristics are defined in Section 2.2 on page 41. The input buffer has an enable input. When enabled,

the buffer inputs the pin’s logic level to the on-chip modules. When disabled, the input is blocked to prevent supply leakage

currents.

Weak Pull-Up

The weak pull-up is enabled when the corresponding bit of PyWPU is set (1). This pull-up can prevent the input from being

in an undefined state.

Alternate Function

PyALT controls the use of each of the port pins for GPI or for the pin’s respective alternate function.

When a PxALT bit is cleared (0):

●The corresponding pin is used as a GPI pin.

●The input buffer is routed to the Data Input register.

In this case, the input buffer is blocked, except when the buffer is actually being read.

●The pull-up is enabled when both the PyWPU is set and the output buffer is put in TRI-STATE.

When a bit in PxALT is set (1):

●The corresponding pin is used for an alternate function (i.e., a signal to some other PC87591x module).

●The input buffer is always enabled; therefore, to minimize current consumption, the signal should be held above VCC−0.2

or below GND+0.2V.)

●The pull-up is enabled when both the PyWPU is set and the output buffer is put in TRI-STATE.

Data Input

The Data Input (PyDIN) register returns the current value/state of the pin. This register can always be read.

4.5.4 GPO Port Pz

Output Only Port with Alternate Function

The General-Purpose Output (GPO) port (Pz) is a subset of the GPIO functions. It enables the port to be used as a GPO

port or as an output signal for an alternate function. Figure 36 illustrates its functionality.

Output Buffer

The output buffer is a TRI-STATE buffer. The output type (i.e., CMOS or TTL) and its driving capabilities are described in

Section 2.2 on page 41.

Alternate Function

The PzALT controls the use of each of the port pins for GPO or for the pin’s respective alternate function.

When a PzALT bit is cleared (0):

●The corresponding pin is used as a GPO pin.

●The output buffer is controlled by the Data Output register.

When a bit in PzALT is set (1):

●The corresponding pin is used for an alternate function (i.e., a signal from or to some other module of the PC87591x).

●The output buffer data is controlled by signals coming from the alternate module.

Data Output

MUX

Alt Device

Alt

PzAlt

Alternate

Function

Data Out

(PzDOUT)

Alt

Figure 36. GPO Port Pz Schematic Diagram

Data Output

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Data Output

The Data Out (PzDOUT) register holds the data to be driven onto the pin.

4.5.5 GPIO Port Pw

GPIO Port Signals Shared with Development System Signals

The Pw GPIO port enables access to input and output pins. Depending on the operating environments, some pins of the I/O

ports may be dedicated to functions other than input or output. In this case, low-cost external logic can be used to perform

the I/O functions with binary and cycle-by-cycle compatibility (see Section 4.1.8 on page 80 for details of the Expansion I/O

protocol). The Alternate Functions Table (Table 8 on page 54) defines the environment in which each port is implemented

off-chip and the pin that performs its alternate function.

The I/O Expansion protocol is used to access the off-chip implementation of the port’s registers (PwDIR, PwDOUT, PwDIN),

when the port pins are used by DEV environment. This enables binary compatibility between all environments.

To enable cycle-by-cycle compatibility in all environments, the access time to any of the registers is identical for on-chip and

off-chip implementation of the ports (i.e., as configured for the BIU I/O zone).

Figure 37 illustrates its functionality.

Output Buffer

The output buffer is a TRI-STATE buffer. Its output type (i.e., CMOS or TTL) and its driving capabilities are described in

Section 2.2 on page 41.

Input Buffer

The I/O port input buffer characteristics are defined in Section 2.2 on page 41. The input buffer has an enable input. When

enabled, the buffer inputs the pin’s logic level to the on-chip modules. When disabled, the input is blocked to prevent supply

leakage currents.

Port Direction

The Port Direction register (PwDIR) controls the direction of the port. When set (1), each bit in PwDIR register causes the

corresponding port signal to serve as an output port, thus enabling the output buffer. When cleared, the port serves as an

input port signal, thus putting the output buffer in TRI-STATE.

Data Output

The Data Output (PwDOUT) register holds the data to be driven onto the pin when the corresponding pin is set as GPIO and

its direction is set as output.

Data Input

The Data Input (PwDIN) register returns the current value/state of the pin. This register can always be read.

Open Drain

To use the GPIO pin as an inverting open-drain output buffer, the software should clear the corresponding bit in Data Output

(PwDOUT) register and then use the Direction register to set the value to the port pin.

Data Output

Direction

Data Input Register

Data Input Read

Data Out

(PwDOUT)

Direction

(PwDIR)

PwDIN

Figure 37. GPIO Port Pw Schematic Diagram

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When the signal’s direction is set as output (1), a value of 0 is forced. When the direction is set for input (0), the signal is in

TRI-STATE and is not forced low.

4.5.6 GPIO Port Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

GPIO Register Map

Port Alternate Function Registers (PxALT, PyALT and PzALT)

These registers control the use of each of the Px, Py and Pz pins, respectively, as GPIO ports or as alternate functions.

●When cleared (0), each bit in PxALT, PyALT or PzALT enables the corresponding pin as a GPIO signal.

●When set (1), each bit enables the corresponding pin as an alternate function.

These registers are cleared (0) on reset, except when otherwise noted in Appendix A on page 408.

Location: See Appendix A

Type: R/W

Mnemonic Register Name Type

PxALT Port Px Alternate Function R/W

PyALT Port Py Alternate Function R/W

PzALT Port Pz Alternate Function R/W

PxDIR Port Px Direction R/W

PwDIR Port Pw Direction R/W

PxDOUT Port Px Data Output R/W

PzDOUT Port Pz Data Output R/W

PwDOUT Port Pw Data Output R/W

PxDIN Port Px Data Input RO

PyDIN Port Py Data Input RO

PwDIN Port Pw Data Input RO

PxWPU Px Weak Pull-Up R/W

PyWPU Py Weak Pull-Up R/W

Bit 76543210

Name Px Pins Alternate Function Enable

Reset 00000000

Bit 76543210

Name Py Pins Alternate Function Enable

Reset 00000000

Bit 76543210

Name Pz Pins Alternate Function Enable

Reset 00000000

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Port Direction Registers (PxDIR and PwDIR)

These registers configure the direction of the Px and Pw pins.

●When cleared (0), each bit in PxDIR or PwDIR deﬁnes the corresponding pin as input.

●When set (1), each pin is deﬁned as output.

PxDIR and PwDIR are cleared (0) on reset except when otherwise noted in Appendix A. Clearing these registers configures

all the pins in port Px and Pw as input. Some specific reset values differ, as described in Appendix A on page 408.

Location: See Appendix A

Type: R/W

Port Data Output Register (PxDOUT, PzDOUT and PwDOUT)

Writing to PxDOUT, PzDOUT or PwDOUT registers sets the values of the output pins in ports Px, Pz and Pw, respectively.

Reading from one of these registers returns the last value written to the register.

Location: See Appendix A

Type: R/W

Port Data Input Registers (PxDIN, PyDIN and PwDIN)

Reading from PxDIN, PyDIN or PwDIN returns the current value of the pins in port Px, Py and Pw, respectively.

Location: See Appendix A

Type: RO

Bit 76543210

Name Px Port Direction

Reset 00000000

Bit 76543210

Name Pw Port Direction

Reset 00000000

Bit 76543210

Name Px Port Output Data

Bit 76543210

Name Pz Port Output Data

Bit 76543210

Name Pw Port Output Data

Bit 76543210

Name Px Port Input Data

Bit 76543210

Name Py Port Input Data

Bit 76543210

Name Pw Port Input Data

Reset

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Port Weak Pull-Up Registers (PxWPU, PyWPU)

These registers control the pull-up for the related pin, when it used either as GPIO or in its alternate function. The pull-up is

enabled when the corresponding bit of PxWPU or PyWPU is set and the port buffer is in TRI-STATE. Otherwise, the pull-up

is disabled (i.e., high impedance).

On reset, PxWPU or PyWPU is cleared (0), disabling all pull-ups.

Location: See Appendix A

Type: R/W

Bit 76543210

Name Px Port Weak Pull-Up Enable

Reset 00000000

Bit 76543210

Name Py Port Weak Pull-Up Enable

Reset 00000000

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4.6 PS/2 INTERFACE

The PS/2 protocol is an industry-standard, PC-AT-compatible interface for keyboards. It uses a two-wire bidirectional TTL

interface for data transmission. Several vendors also supply PS/2 mouse products and other pointing devices that employ

the same type of interface.

The PC87591x provides four PS/2 data transfer channels. Each channel has two quasi-bidirectional signals that serve as

direct interfaces to an external keyboard, mouse or any other PS/2-compatible pointing device. Since the four channels are

identical, the connector ports are interchangeable.

4.6.1 Features

●Four PS/2 channels

●Enable/Disable for each of the four channels

●Automatic hardware shift mechanism

●Hardware support for PS/2 auxiliary device protocol

●Processor interrupts at the beginning and end of data transfer

●Optional software-based PS/2 implementation

4.6.2 General Description

In the previous generation of keyboard controllers, firmware executed the PS/2 device interface by toggling the interface

signals. The PC87591x (and its predecessor, the PC87570) supports this bit toggling mode via either polling or interrupt-

driven clock edge detection.

PS/2 devices’ firmware is significantly simplified through the use of a hardware accelerator mechanism. The accelerator in-

cludes an 8-bit shift register, a state-machine and control logic that handle both the incoming and outgoing data. It reduces

code overhead, performance requirements and reduces the overall interrupt latency from the core firmware. The hardware

is designed to meet the PS/2 device interface as defined in Keyboard and Auxiliary Device Controller (Types 1 and 2),

August 1988.

Section Naming conventions

●In this section, the term “channel” describes the interface to one of the PS/2 devices and its two associated signals

(clock and data).

●The term “shift mechanism” refers to the hardware accelerator.

●The term “PS/2 interface” refers to the entire mechanism.

Interface Signals

The PS/2 interface includes eight external signals (PSCLK4-1 and PSDAT4-1) and six registers.

Module Block Diagram

A schematic description of the PS/2 interface appears in Figure 38. The interface to the three channels is symmetric and

only channel 1 is detailed in the figure.

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Quasi-Bidirectional Drivers

The quasi-bidirectional drivers have an open-drain output (Q2), an internal pull-up (Q3) and a low-impedance pull-up(Q1).

Q2 pulls the signal low whenever the output buffer data is “0”. The weak pull-up (Q3) is active whenever the output buffer

data is “1” and WPUEN in PSCON register is set (1). The low impedance pull-up is active whenever the PC87591x changes

the output data buffer from “0” to “1”, thereby reducing the low-to-high transition time. The length of time that the low-imped-

ance pull-up is active is determined by HDRV field in PSCON register. A schematic description of this output driver appears

in Figure 39.

Interrupt Signals

The firmware can use an interrupt-driven scheme to implement the PS/2 device interface. When the shift mechanism is not

in use, four interrupts are available (PSINT4-1), one for each channel. (PSINT4 is not connected to the ICU as a separate

input, the MIWU PSCLK4 input should be used instead). When the shift mechanism is in use, only one interrupt signal is

used (PSINT1). More details on the use of the interrupts are provided in Section 4.6.4 on page 125. Figure 40 illustrates the

interrupt scheme with the associated enable bits.

Channel 4

Channel 3

Channel 1

Channel 2

Shift Mechanism

EN1

PSCLK1

PSDAT1

DATO1

DATI1 CLKO1

CLKI1

EN2 DATO2

DATI2 CLKO2

CLKI2

EN3 DATO3

DATI3 CLKO3

CLKI3

CLK1

WDAT1

RCLK1

RDAT1

ENSM

PS/2 I/F

Registers

Figure 38. PS/2 Interface Functional Diagram

EN4 DATO4

DATI4 CLKO4

CLKI4

+VCC

Rising Edge

Detector

Output Buffer Data

Input Buffer Data

Figure 39. Quasi-Bidirectional Buffer

WPUEN

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Power Modes

The PS/2 interface is active only when the PC87591x is in Active mode. The shift mechanism should be disabled before

entering Idle mode. In Idle mode, the state of output signals cannot be changed (i.e., the firmware cannot write to PSOSIG

When the PC87591x needs to wake up on a Start bit detection by the MIWU, the PS/2 channels that may serve as wake-up

event sources must be enabled before entering Idle mode. To enable them, set to 1 their corresponding CLK bits in PSOSIG

The MIWU module can be used to identify a start bit in Idle mode and to return the PC87591x to Active mode. The MIWU

receives PSCLK4-1 and PSDAT4-1 signals as inputs (see Table 17 on page 105). The MIWU should be programed to iden-

tify a falling edge on the clock or data lines of the enabled channels. In this configuration, a start bit causes the PC87591x

to switch from Idle mode to Active mode. Once Active mode is reached, the firmware should cancel the transaction just start-

ed and then enable re-transmission of the information by the device.

PS/2 Interface Operation

The PS/2 interface has two basic operating methods: with the shift mechanism disabled and with the shift mechanism en-

abled. The following sections describe how to use the PS/2 interface with each of these operating methods.

4.6.3 Operating With the Shift Mechanism Disabled

The shift mechanism is disabled when EN bit in PSCON register is cleared (0). In this state, the PS/2 clock and data signals

are controlled by the firmware, which performs the PS/2 protocol by manipulating the PS/2 clock and data signals.

Clock Signal Control

CLK4-1 bits in PSOSIG register control the value of the respective clock signals (PSCLK4-1). When one of these bits is

cleared (0), the relevant pin is held low. When set (1), the open-drain output is open and the respective clock signal is either

floating or held high by the pull-up. In this case, an external device can force the respective clock signal low.

When reading PSISIG register, bits RCLK4-1 indicate the current state of the corresponding clock signal.

Data Signal Control

WDAT4-1 bits in PSOSIG register control the value of the respective data signals (PSDAT4-1). When one of these bits is

cleared (0), the relevant data signal is held low. When set (1), the open-drain output is open and the respective data signal

is held high by the pull-up. In this case, an external device can force the respective data signal low.

When reading PSISIG register, bits RDAT4-1 indicate the current state of the corresponding data signal.

Interrupt Generation

When DSMIE bit in PSIEN register is set (1), the clock input signals are connected to the Interrupt Control Unit (ICU) for an

interrupt driven PS/2 protocol. The four interrupts that are generated are PSINT4-1 for channels 4-1, respectively.

The ICU should be programed to detect a falling edge on each of the clock signals. Disabling a channel by writing 0 to the

clock control signals (CLK4-1) may cause a falling edge on a clock signal. When such an interrupt is not desired, clear the

clock control bit (0); then clear the respective pending bit in the ICU (or in the MIWU, for PSINT4). This should be done while

interrupts are disabled. For more details about the ICU, see Section 4.3 on page 98.

EOT bit (PSTAT)

SOT bit (PSTAT)

PSCLK1

PSCLK3

PSCLK2

EOTIE bit (PSIEN)

SOTIE bit (PSIEN) PSINT1

PSINT2

PSINT3

Figure 40. PS/2 Interface Interrupt Signals

PSCLK4

DSMIE bit (PSIEN) PSINT4*

* Use PSCLK4 in the MIWU.

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4.6.4 Operating With the Shift Mechanism Enabled

The shift mechanism is designed to off load the bit level handling of the data transfer from the firmware to a hardware

scheme; this improves system tolerance to interrupt latency. The mechanism includes a shift register and a state machine

that controls the PS/2 protocol.

Figure 41 illustrates the shift mechanism PS/2 data transfer sequence. There are three basic modes: Disabled, Receive and

Transmit. Different states in each mode define the progress of the data transfer. The rest of this section details the use of

the shift mechanism for implementing a PS/2 data transfer.

Reset the Shift Mechanism

Clearing either the shift mechanism enable bit (EN = 0 in PSCON register) or all the channels’ clock bits (CLK4-1 = 0) resets

the shift mechanism. In this state, PSTAT register is cleared (0016), and the state of the PS/2 clock and data signals

(PSCLK4-1 and PSDAT4-1) is set according to the value of their control bits (CLK4-1 and WDAT4-1, respectively).

When the shift mechanism is reset while in an unknown state or while in Transmit Idle state, the firmware should set (1)

WDAT4-1 before the shift mechanism is reset.

Before disabling the shift mechanism, the software should clear (0) CLK4-1 to prevent glitches on the clock signals.

Enable the Shift Mechanism

To enable the shift mechanism, verify that PSOSIG register is set to 4716 and then set (1) EN bit in PSCON register. This

puts the shift register state machine in Receive Inactive or Transmit Inactive state (XMT is 0 or 1, respectively, in PSCON

register). In either of these states, the clock signals (PSCLK4-1) are low and the data signals PSDAT4-1 are either floating

or pulled high.

PS/2 Reset

XMT = 0

XMT = 1

Start Bit

Detected

XMT = 1

EN = 1 and

EN = 0

Disabled

Receive

Inactive

XMT = 0

EN = 1 and

Transmit

Idle

Transmit

Active

Line Control

Bit Detected

End of

Transmission

or CLK4 = 1

Start Bit

Detected

Receive

Idle

CLK1, CLK2, CLK3

Receive

Active

Stop Bit

Detected

End of

Reception

and/or CLK4 = 1

Transmit Mode Receive Mode

EN = 0

CLK1, CLK2, CLK3

and CLK4 = 0

CLK1, CLK2, CLK3

and CLK4 = 0

Transmit

Inactive

Figure 41. Shift Mechanism State Diagram

CLK1, CLK2, CLK3

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Shift Status

The PSTAT register indicates the current status of the shift mechanism. The data transfer process may be in one of the

following three states:

●Shifter Empty:

The shift mechanism is in Receive Inactive, Receive Idle, Transmit Inactive or Transmit Idle state. The PSTAT is

cleared because none of the enabled devices has sent a start bit.

●Start Bit Detected:

The shift mechanism is in Receive Active or Transmit Active state. This indicates that a start bit was identiﬁed for at

least one of the channels and the shift process has begun. SOT bit in PSTAT register indicates the detection of the

start bit and ACH ﬁeld in PSTAT register indicates the active channel (the channel on which the start bit was detect-

ed).

●End of Transaction:

The shift mechanism is in End-of-Reception or End-of-Transmission state. This indicates that the last bit of the trans-

fer sequence was detected (and the data can therefore be read from PSDAT register) or that the data transmission

was completed (for receive and transmit, respectively). EOT bit in PSTAT register indicates transfer completion. If a

parity error was detected in the received data, PERR bit in PSTAT register is set. If a stop bit was detected low in-

stead of high, RFERR bit in PSTAT register is set.

Input Signal Debounce

The PC87591x performs a debounce operation on the clock input signal before determining its logical value. IDB field in

PSCON register determines for how many clock cycles the input signal must be stable to define a change in its value.

Interrupt Generation

The PSINT1 is an interrupt signal generated by the shift mechanism to allow an interrupt driven interface with the firmware.

The ICU should be programed to detect high-level interrupts on the PSINT1 interrupt. See Section 4.3 on page 98 for details

on the ICU. SOTIE and EOTIE bits in PSIEN register mask the interrupt signaling for SOT and EOT bits, respectively, in

PSTAT register.

Receive Mode

Receive Inactive

When the shift mechanism is enabled and bit XMT=0 in PSCON register, the shift mechanism enters Receive mode in the

Receive Inactive state. Receive Idle state is entered when one (or more) of the channels is enabled, by setting the channel

enable bit (CLK4-1 for channels 4-1, respectively). In this state, the shift-mechanism sets the clock and data lines of the

enabled channels high (1) and waits for a start bit.

Receive Idle

In the Receive Idle state, the PS/2 interface waits for input from any one of the enabled channels. The first of the enabled

channels to send a start bit is selected for handling by the shift mechanism. The other two channels are disabled by forcing

“0” on their clock lines.

Start Bit Detection

The start bit is identified by a falling edge on the clock signal while the data signal is low (0).

If the start bit is identified simultaneously in more than one channel, one channel is selected for receive, while the other chan-

nel’s transfer is aborted. The channel with the lower number is selected (i.e., channel 1 has priority over channels 2, 3 and

4, channel 2 has priority over channel 3 and 4 and channel 3 has priority over channel 4). The data transfer in the other

channels is aborted before 10 data bits have been sent (by forcing the clock signal to 0), and the transmitting PS/2 device

resends its data when its interface is enabled again by the firmware. This mechanism ensures that no incoming data is lost.

When the hardware sets (1) SOT bit and designates the selected channel in ACH field, this indicates receipt of the start bit

in PSTAT register. In addition, if SOTIE is set in PSIEN register, an interrupt signal to the ICU is set high. The firmware may

use this interrupt to start a time-out timer for the data transfer.

Receive Active

After identifying the start bit, the shift mechanism enters the “Receive-Active” state. In this state the clock signal of the se-

lected device (PSCLK1, PSCLK2, PSCLK3 or PSCLK4) sets the data bit rate. On each falling edge of the clock, new data

is sampled on the data signal of the active channel (i.e., PSDAT1 PSDAT2, PSDAT3 or PSDAT4).

Following the start bit, eight bits of data are received (clocks 2 through 9); a parity bit follows (10th clock) and then a stop bit

(11th clock). The stop bit is indicated by a falling edge of the clock with the data signal high (1). If the 11th clock is identified

with data low, the receive frame error bit (RFERR in PSTAT register) is set but the clock is treated as the stop bit.

After the parity is received, the shift mechanism checks the incoming data for parity errors. If there are eight data bits with a

value of 1 and the parity bit is even, PERR bit in PSCON register is set, indicating a parity error.

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End of Receive

When the stop-bit is detected, the shift mechanism enters the “End-Of-Reception” state. In this state, the shift mechanism:

●Disables all the clock signals by forcing them low

●Sets End-Of-Transaction status bit (EOT = 1 in PSTAT register)

●If EOTIE bit in PSTAT register is set, it asserts (1) the interrupt signal to the ICU.

The shift mechanism stays in this state until it is reset.

Figure 42 illustrates the receive byte sequence, as defined by the PS/2 standard.

Transmit Mode

Transmit Inactive

When the shift mechanism is enabled and XMT bit in PSCON register is set (1):

●The shift mechanism enters Transmit mode in Transmit Inactive state with all clock signals low and data signals high

(PSOSIG = 4716).

●The ﬁrmware writes the data to be transmitted to the PS/2 data register (PSDAT).

●The data line of the channel to be transmitted is forced low by the ﬁrmware clearing its data bit (WDAT4-1 for chan-

nels 4-1, respectively).

Transmit Idle

The Transmit Idle state can be entered by setting the channel enable bit (CLK4-1 for channel 4-1, respectively). This enables

the channel to be used for transmission. In this state, the shift-mechanism sets the clock of the enabled channel high (1)

while the data line of that channel is held low and waits for a start bit. When a PS/2 device senses the clock signal high with

the data signal low, it identifies a transmit request from the PC87591x.

The three channels not in use are disabled by forcing “0” on their clock lines.

Start Bit Detection

The start bit is identified by a falling edge on the clock signal while the data signal is low (0).

When a start bit is detected, data transmission begins by outputting bit 0 (LSB) of the transmitted data and setting data bits

WDAT4-1 in PSOSIG register. This allows bit 0 of the transmitted data to be output on the PS/2 data signal (PSDAT1,

PSDAT2, PSDAT3 or PSDAT4, according to the active channel).

In addition, the hardware sets the SOT bit (to 1) and stores the active channel number in ACH field, indicating transmission

of the start bit in PSTAT register. Note that if SOTIE bit in PSIEN register is set, an interrupt signal to the ICU is set high.

The firmware can use this interrupt to start a time-out timer for the data transfer.

Transmit Active

After identifying the start bit, the shift mechanism enters the Transmit Active state. The clock signal of the selected device

(PSCLK1, PSCLK2, PSCLK3 or PSCLK4) sets the data bit rate.

CLK

DATA Bit 0 Parity Bit Stop BitStart Bit

1st

CLK 2nd

CLK 10th

CLK 11th

CLK

Figure 42. PS/2 Receive Data Byte Timing

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After each of the next seven falling edges of the clock line, one more data bit (bits 1 through 7) is driven on the data line of

the active channel (either PSDAT1, PSDAT2, PSDAT3 or PSDAT4).

On the ninth falling edge of the clock, the parity bit is output. The parity bit is high (1) if the number of bits with a value of 1

in the transmitted data was even (i.e., odd parity).

The tenth falling edge causes a 1 to be output as a stop bit. The data signal remains high to allow the PS/2 device to send

the line control bit.

The auxiliary device then completes the transfer by sending the line-control bit. The line-control bit, is identified by the data

signal being low after the 11th falling edge of the clock.

End of Transmission

The End-Of-Transmission state is entered when the line-control bit is detected. In response, the shift mechanism holds all

clock signals low, and if the internal pull-up is enabled, all data signals are pulled high by the internal pull-up.

The End-Of-Transaction flag (EOT in PSTAT register) is set to indicate that the transmit operation was completed; in addi-

tion, if EOTIE bit in PSIEN register is set, the interrupt signal to the ICU is set high.

The shift mechanism stays at this state until being reset.

Figure 43 illustrates the transmit byte sequence, as defined by the PS/2 standard.

Transfer Abort

At each stage of a receive or transmit operation, the transaction can be aborted by clearing all four channel enable bits

(CLK4-1) in PS/2 Output Signal register (PSOSIG) to 0. This resets the shifter state machine and puts it in the Enabled In-

active state. If the shift mechanism is in Transmit Inactive or Transmit Idle state, WDAT4-1 bits should also be set.

4.6.5 PS/2 Interface Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

CLK

DATA Bit 0 Parity Bit Stop BitStart Bit

1st

CLK 2nd

CLK 9th

CLK 11th

CLK

I/O

Inhibit 10th

CLK

Figure 43. PS/2 Transmit Data Byte Timing

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PS/2 Register Map

PS/2 Data Register (PSDAT)

The PSDAT register is a byte-wide read/write register. In Receive mode, PSDAT holds the data received in the last message

from the PS/2 device. In Transmit mode, the data to be shifted out is written to this register. When the PS/2 i/f is reset, the

contents of this register become invalid.

On reset, the PS/2 interface is set to Receive mode. In this mode, PSDAT should be read only when EOT bit in PSTAT

Setting the transmit enable bit in PSCON register to 1 (XMT = 1 in PSCON register) puts the PS/2 interface in Transmit

mode. PSDAT should be written only when in Transmit mode and when all four channel enable bits CLK4-1 in PSOSIG reg-

ister are cleared (0).

Location: 00 FE8016

Type: R/W

PS/2 Status Register (PSTAT)

The PSTAT register is a byte-wide read-only register. It contains the status information on the data transfer on the PS/2

ports. All non-reserved bits of PSTAT are cleared (0) on reset when CLK1, CLK2 and CLK3 in PSOSIG are cleared and

when EN bit in PSCON register is cleared. Reading PSTAT does not clear any of its bits.

Location: 00 FE8216

Type: RO

Mnemonic Register Name Type

PSDAT PS/2 Data Register R/W

PSTAT PS/2 Status Register RO

PSCON PS/2 Control Register R/W

PSOSIG PS/2 Output Signal Register R/W

PSISIG PS/2 Input Signal Register RO

PSIEN PS/2 Interrupt Enable Register R/W

Bit 76543210

Name Data

Bit Description

7-0 Data. Contains the data received in the last message (or that is transmitted in the following transmission). Bit 0

is the ﬁrst bit to be shifted (LSB).

Bit 76543210

Name Reserved RFERR ACH PERR EOT SOT

Reset x 0000000

Bit Description

0SOT (Start of Transaction). When set to 1, indicates that a start bit was detected. The ACH ﬁeld (bits 5-3 of

this register) indicates which of the channels it was detected on.

1EOT (End of Transaction). When set to 1, Indicates that a PS/2 data transfer was completed, i.e., a stop bit

was detected at Receive mode or a line control bit was detected at Transmit mode.

2PERR (Parity Error).

When set to 1, indicates that a parity error was detected in the last data transfer.

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PS/2 Control Register (PSCON)

ThePSCONregister is an 8-bit read/write register. It controls the operation of the PS/2 interface by enabling it and controlling

the data transfer direction. On reset, PSCON is set to 0016.

Location: 00 FE8416

Type: R/W

5-3 ACH (Active Channel). Deﬁnes which of the PS/2 channels is currently active (i.e., a start bit was detected). In

case more than one channel become active simultaneously, only the one with the highest priority (lowest

number) is ﬂagged.

Bits

5 4 3 Description

0 0 0: None of the channels is active

0 0 1: Channel 1

0 1 0: Channel 2

1 0 0: Channel 3

1 0 1: Channel 4

6RFERR (Receive Frame Error).

When set to 1, indicates that the stop bit in a received frame was detected low instead of high.

7Reserved.

Bit 76543210

Name WPUEN IDB HDRV XMT EN

Reset 00000000

Bit Description

0EN (Shift Mechanism Enable).

0: The hardware shift mechanism is disabled and the software controls and monitors the PS/2 signals using

PSOSIG and PSISIG registers.

1: The hardware shift mechanism is enabled. The enabled channels are controlled by PSOSIG, and Transmit/Re-

ceive mode is controlled by the XMT bit.

1XMT (Transmit Enable).

0: Receive mode.

1: Causes the PS/2 interface to enter Transmit mode.

3-2 HDRV (High Drive). Deﬁnes the quasi-bidirectional buffers’ behavior on transition from low to high. HDRV

deﬁnes the period of time for which the output is pulled high with a low-impedance drive (when the PC87591x

changes the output level from low to high). This period is a function of the PC87591x clock as follows:

Bits

3 2 Description

0 0: Disabled

0 1: Low-impedance drive for one clock cycle

1 0: Low-impedance drive for two clock cycles

1 1: Low-impedance drive for three clock cycles

Bit Description

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PS/2 Output Signal Register (PSOSIG)

The PSOSIG register is a byte-wide, read/write register. It allows setting the value of the PS/2 port signals. When the shift

mechanism is enabled, the clock control bits in this register define the active channel(s). On reset, this register is set to 4716.

Location: 00 FE8616

Type: R/W

6-4 IDB (Input Debounce). Deﬁnes the number of PC87591x clock cycles during which the clock input is expected

to be stable before the shift mechanism identiﬁes its new value. This protects the shift mechanism from false

edge detections. The number of PC87591x clock cycles for which the input should be stable before an edge is

detected is as follows:

Bits

6 5 4 Description

0 0 0: One cycle

0 0 1: Two cycles

0 1 0: Four cycles

0 1 1: Eight cycles

1 0 0: 16 cycles

1 0 1: 32 cycles

7WPUEN (Weak Pull-Up Enable).

0: The pull-up is disabled. In this state, the system must ensure that PS/2 interface signals are not floating, to en-

able proper PS/2 operation.

1: Enables the internal pull-up of the output buffer. The pull-up remains active as long as the buffer does not drive

the signal to low level.

Bit 76543210

Name CLK4 WDAT4 CLK3 CLK2 CLK1 WDAT3 WDAT2 WDAT1

Reset 01000111

Bit Description

0WDAT1 (Write Data Signal Channel 1). Controls the data output to channel 1 data signal (PSDAT1). Use of

this bit depends on whether or not the shift mechanism is enabled.

•When the shift mechanism is disabled (EN bit in PSCON register is set to 0), the data in WDAT1 is output to

PSDAT1 signal.

−If WDAT1 is cleared (0), the output buffer data is 0 (i.e., PSDAT1 is forced low).

−If WDAT1 is set (1), the output buffer data is 1 (i.e., PSDAT1 is pulled high by the internal pull-up and may

be pulled low by an external device).

•When the shift mechanism is enabled (EN=1), WDAT1 should be set to 1, except when the shift mechanism is

in Transmit mode. In this case, when in transmit-inactive and it is intended to transmit data to channel 1, the

firmware should clear WDAT1 bit to force the transmit signaling (low) to the PS/2 device.

Note: WDAT1 is set by the hardware after the PC87591x detected a start bit (i.e., on entering Transmit Active

state). If a transmission is aborted before Transmit Active state, WDAT1 should be set (1) prior to disabling

the channel.

1WDAT2 (Write Data Signal Channel 2). Controls the data output to channel 2 data signal (PSDAT2). For more

information, see the description of bit 1 (above).

2WDAT3 (Write Data Signal Channel 3). Controls the data output to channel 3 data signal (PSDAT3). For more

information, see the description of bit 1 (above).

Bit Description

Embedded Controller Modules (Continued)

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PC87591E/S/L

Note: When CLK1, CLK2, CLK3 and CLK4 are all 0, this is interpreted as a shift mechanism reset. In this case, the PSTAT

PS/2 Input Signal Register (PSISIG)

The PSISIG register is an 8-bit read only register. It provides the current value of the PS/2 port signals.

Location: 00 FE8816

Type: RO

3CLK1 (Enable Channel 1)

0: Forces the PSCLK1 pin low (0) and disables channel 0 of the shift mechanism.

1: Depends on whether or not the shift mechanism is enabled.

•When the shift mechanism is enabled (EN bit in PSCON register is set to 1), channel 1 of the PS/2 ports

is enabled.

•When the shift mechanism is disabled (EN bit in PSCON register is set to 0), the clock line output buffer

data is 1 (i.e., the signal is pulled high by the pull-up, if enabled, and may be pulled low by an external de-

vice).

4CLK2 (Enable Channel 2). Same as bit 3 of this register (described above) but for channel 2.

5CLK3 (Enable Channel 3). Same as bit 3 of this register (described above) but for channel 3.

6WDAT4 (Write Data Signal Channel 4). Controls the data output to channel 4 data signal (PSDAT4). For more

information, see the description of bit 1 (above).

7CLK4 (Enable Channel 4). Same as bit 3 of this register (described above) but for channel 4.

Bit 76543210

Name RCLK4 RDAT4 RCLK3 RCLK2 RCLK1 RDAT3 RDAT2 RDAT1

Bit Description

0RDAT1 (Read Data Signal Channel 1). The current value of the channel 1 data signal (PSDAT1).

1RDAT2 (Read Data Signal Channel 2). The current value of the channel 2 data signal (PSDAT2).

2RDAT3 (Read Data Signal Channel 3). The current value of the channel 3 data signal (PSDAT3).

3RCLK1 (Read Clock Signal Channel 1). When read, returns the current value of the channel 1 clock signal

(PSCLK1).

4RCLK2 (Read Clock Signal Channel 2). When read, returns the current value of the channel 2 clock signal

(PSCLK2).

5RCLK3 (Read Clock Signal Channel 3). When read, returns the current value of the channel 3 clock signal

(PSCLK3).

6RDAT4 (Read Data Signal Channel 4). The current value of the channel 4 data signal (PSDAT4).

7RCLK4 (Read Clock Signal Channel 4). When read, returns the current value of the channel 4 clock signal

(PSCLK4).

Bit Description

Embedded Controller Modules (Continued)

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PS/2 Interrupt Enable Register (PSIEN)

The PSIEN register is an 8-bit read/write register. It enables/disables the various interrupts generated by the PS/2 module.

Bits in PSIEN register may be cleared to 0 only when interrupts are disabled (i.e., in the core, I or E bits in PSR register are

0) or when the corresponding interrupts in the ICU are masked. Bits in PSIEN register may be set to 1 at any time. On reset,

non-reserved bits of PSIEN are cleared.

Location: 00 FE8A16

Type: R/W

Bit 76543210

Name Reserved DSMIE EOTIE SOTIE

Reset 00000000

Bit Description

0SOTIE (Start of Transaction Interrupt Enable). Used for enabling the interrupt generation on a transaction

start detection.

0: SOT bit in PSTAT register does not affect the interrupt signal.

1: The interrupt signal (PSINT1) to the ICU is active (1) whenever SOT bit in PSTAT register is set.

Note: Once set, SOT is not cleared until the shift mechanism is reset. Therefore SOTIE should be cleared on

the ﬁrst occurrence of an SOT interrupt. SOTIE should be set (1) when the PS/2 module is programed to

handle the impending transfer.

1EOTIE (End of Transaction Interrupt Enable). Used for enabling the interrupt generation on an End of

Transaction detection.

0: EOT bit in PSTAT register does not affect the interrupt signal.

1: The interrupt signal (PSINT1) to the ICU is active (1) whenever EOT bit in PSTAT register is set.

Note: Once set, EOT is not cleared until the shift mechanism is reset. Therefore EOTIE should be cleared on

the ﬁrst occurrence of an EOT interrupt. EOTIE should be set (1) when the PS/2 module is programed to

handle the impending transfer.

2Disabled Shift Mechanism Interrupt Enable (DSMIE). Used for enabling the interrupt generation when the

shift mechanism is disabled.

0: The four interrupt signals are low. Note that PSINT1 may be activated (1) by other interrupt sources ofthe module.

1: The clock input signals are connected to the Interrupt Control Unit (ICU), to allow implementing an interrupt driv-

en PS/2 protocol. The four interrupts generated are PSINT1, PSINT2, PSINT3 and PSINT4, for channels 1, 2,

3 and 4, respectively. Note that PSINT4 is connected to the MIWU and not directly to the ICU.

Note: When the shift mechanism is disabled, no debounce is applied to the PSCLK inputs before producing the

interrupt signals, except for local synchronization.

7-3 Reserved.

Embedded Controller Modules (Continued)

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PC87591E/S/L

4.7 MULTI-FUNCTION 16-BIT TIMER (MFT16)

The PC87591x includes two Multi-Function Timer (MFT) modules. The registers of each module are prefixed with Tn and

the signals are suffixed with an n (where n is the module’s number, i.e., 1 or 2). Each MFT16 module consists of two func-

tional units designed to satisfy a wide range of application requirements. The units include:

●Clock Source Unit that contains a pre-scaler with one clock source selector for each counter.

●Main timer/counter and action unit that contains two counters, two reload registers for PWM, Input Capture or

Counter modes.

●Mode selector/control unit that deﬁnes the function of the I/O pins and the interrupts.

Figure 44 shows the contents of an MFT16 and the top-level interaction. The rest of the section describes an MFT16 module.

4.7.1 Features

●Two 16-bit programmable timers/counters

●Two 16-bit reload/capture registers. These registers are used either as reload registers or capture registers, depend-

ing on the mode of operation.

●A 5-bit fully programmable clock pre-scaler

●Clock source selectors for each counter. These enable each counter to operate in:

—Pulse accumulate mode

—External event mode

—Prescaled system clock mode

—Slow speed clock input mode (where applicable)

●Two I/O pins (TAn and TBn), with programmable edge detection; these operate as:

—Capture inputs

—Capture and preset inputs

—External event (clock) inputs

—PWM outputs

●Two interrupts, one for each counter, that can be generated/ triggered by:

—Timer underﬂow

—Timer reload

—Input capture

●Four pending bits, which can be polled by software, are associated with the two interrupts.

Reload/Capture A

Counter 1

Reload/Capture

Timer/Counter Timer/Counter and Action

Clock

System

Clock

TBn

Toggle/Capture/Interrupt

& Control

PWM/Capture/Counter Mode Select

TAn

External Event

Interrupt A

Interrupt B

Slow

Clock

Figure 44. MFT16 Functional Diagram

32.768 KHz

Source

and

TnCRA

Timer/Counter 1

TnCNT1

Reload/Capture B

TnCRB

Timer/Counter 2

TnCNT2

Clock

Counter 2

Clock

Pre-Scaler

Embedded Controller Modules (Continued)

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4.7.2 Clock Source Unit

The clock source unit, as shown in Figure 45, contains two clock selectors for each counter and a 5-bit clock pre-scaler.

Pre-Scaler

The 5-bit clock pre-scaler consists of a pre-scaler register and a 5-bit counter, allowing the timer to run with a prescaled

clock. The system clock is divided by the value contained in TnPRSC+1. The minimum counter clock frequency is thus the

system clock divided by 32, and the maximum counter clock frequency is equal to the system clock. The pre-scaler register,

TnPRSC, can be read or written by software at any time. The pre-scaler counter is a 5-bit down counter which can not be

read or written by software. The 5-bit counter and the pre-scaler register TnPRSC are cleared on reset

External Event Clock

The TBn I/O pin can be selected as an external event input clock source for either of the two 16-bit counters. The polarity of

the input signal is programmable to trigger a count if either a rising or a falling edge is detected on TBn. The minimum pulse

width of the external signal is one system clock cycle; thus the maximum frequency with which the counter can run in this

mode is limited to half the system clock frequency.

Note: An External Event clock is not available in Dual Channel Capture mode because this mode requires TBn as an input.

Pulse Accumulate Mode

In Pulse Accumulate mode, the counter can also be clocked while an external signal on TBn is either high or low. In this

configuration, the output of the pre-scaler is gated with an external signal applied on TBn input. This mode can be used to

obtain a cumulative count of pre-scaler output clock pulses, as shown in Figure 46.

Note: Pulse Accumulate mode is not a vailable in Dual Channel Capture mode because this mode requires TBn as an input.

Slow-Speed Clock

A slow-speed clock of 32.768 KHz can be used as a clock source for the two 16-bit counters. The MFT16 synchronizes the

slow-speedclockwiththesystemclock.Therefore,themaximum input frequency of the slow-speed clock is the system clock

rate divided by four.

Some power save modes stop the system clock completely. When this occurs, the timer stops counting the slow-speed clock

until the system clock resumes. While operating in a power-save mode that uses a slow system clock, the slow-speed clock

source for the timer can only be used if it is at least four times faster than the slow- speed clock for the counter.

Pre-Scaler Register

TPRSC

Pre-Scaler Counter

5-Bit

System

Clock

Reset

TBn

Pulse

Accumulate

External

Event

No Clock

Prescaled

Clock

Counter 1

Clock

Select

Counter 2

Clock

Select

Counter 1

Clock

Counter 2

Clock

Synchr.

Slow Speed

Clock

Synchr.

Figure 45. Clock Pre-Scaler and Selector

Embedded Controller Modules (Continued)

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Counter Clock Source Select

The clock source unit contains two clock source selectors that allow the clock source to be selected independently for each

of the two 16-bit counters from one of the following sources:

●No clock, in which case the counter is stopped

●Prescaled system clock

●External Event count based on TBn

●Pulse Accumulate mode based on TBn

●Slow Speed Clock i.e., 32.768 KHz

4.7.3 Timer/Counter and Action Unit

The timer/counter and action unit consists of two 16-bit counters, TnCNT1 and TnCNT2, in addition to two 16-bit reload/cap-

ture registers, TnCRA and TnCRB. The timers are down counters capable of triggering events on underflow detection (count

from 000016 to FFFF16). In addition, it contains the mode control logic which allows the timer to operate in any of four oper-

ation modes described below.

Different interrupts can be triggered on certain conditions, and the functionality of the I/O pins changes depending on the

mode of operation. Therefore the interrupt control and the I/O control are an integral part of the timer/counter unit.

Operation Modes

The MFT16 can be configured to operate in any one of four modes, as summarized in Table 18 and described in this section.

Mode 1, PWM and Counter

PWM can be used to generate precise pulses of known width and duty cycle on the TAn pin. The timer is clocked by the

instruction clock. An underflow causes the timer register to be reloaded alternately from the TnCRA and TnCRB registers

and optionally causes TAn output to toggle. Thus, the values stored in TnCRA and TnCRB registers control the high and

low time of the signal produced on TAn. In PWM mode, timer/counter 2 can be used either as a simple system timer or as

an external event counter. The counter can be loaded by software with a specific value; the counter can then generate an

interrupt after the pre-programed number of external events have been received on TBn input.

Table 18. Operation Modes

Mode Description Timer/Counter 1

(TnCNT1) Reload/Capture A

(TnCRA) Reload/Capture B

(TnCRB) Timer/Counter 2

(TnCNT2)

1PWM and system

timer or external

event counter Counter for PWM Auto Reload A =

PWM time 1 Auto reload = PWM

time 2 System Timer or ex-

ternal event counter

2Dual input capture

and system timer Capture A and B

time base Capture counter 1

value on TAn event Capture counter 1

value on TBn event System Timer

3Dual independent

timer Time base for ﬁrst

timer Reload register for

timer/counter 1 Reload register for

timer/counter 2 Time base for sec-

ond timer

4Input capture and

timer Time base for ﬁrst

timer Reload register for

timer/counter 1 Capture counter 1

value on TBn event Capture B time base

TBn

Pre-Scaler Output

Counter Clock

Figure 46. Pulse Accumulate Mode

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Figure 47 shows a block diagram of the timer operating in mode 1. In PWM mode, counter 1, TnCNT1, functions as the time

base for the PWM timer. Counter 1 counts down at the clock rate selected via the counter 1 clock selector. When an under-

flow occurs, the timer register is reloaded alternately from the TnCRA and TnCRB registers, and counting proceeds down-

ward from the loaded value. On reset, and every time this mode is entered, the first reload in this mode is from the TnCRA

register. Once enabled, the counter starts counting down from the value currently loaded to it. At the first underflow, the timer

is loaded from TnCRA; on the second underflow, it is loaded from TnCRB; on the third underflow, it is loaded from TnCRA,

and so on. Note that every time the counter is stopped through the selection of “No-Clock” in the counter 1 clock selector

(TnCKC), it obtains its first reload value after it has been re-started from TnCRA register.

The timer can be configured to toggle TAn output bit on underflow. This results in the generation of a clock signal on TAn,

with the width and duty cycle controlled by the values stored in TnCRA and TnCRB registers. This PWM clock is processor-

independent because once the timer is set up, no more interaction is required by software (and therefore the CPU) to gen-

erate a continuous PWM signal. Software can select the initial value of the PWM output signal as either high or low. See

“Timer I/O Functions” on page 141 for additional details. The timer can be configured to generate separate interrupts on re-

load from TnCRA and TnCRB. The interrupts can be enabled or disabled under software control. The TAnPND or TnBPND

flags, respectively, which are set by the hardware on occurrence of a timer reload, indicate which interrupt occurred. See

Section 4.7.4 on page 140 for detailed information.

In this mode of operation, timer/counter 2 can be used as a simple system timer, an external event counter or a pulse accu-

mulate counter. Counter TnCNT2 counts down with the clock selected via the counter 2 clock selector, and TnCNT2 can be

configured to generate an interrupt on underflow if the interrupt is enabled by TnDIEN bit. See Section 4.7.4 on page 140

for detailed information.

Mode 2, Dual Input Capture

Dual Input Capture mode can be used to precisely measure the frequency of an external clock that is slower than the se-

lected clock source frequency or to measure the elapsed time between external events. A transition received on the TAn or

TBn pin causes a transfer of timer/counter 1 contents to TnCRA or TnCRB register, respectively. In this mode, timer/counter

2 can be utilized as a system timer that is pre-loaded by software and generates an interrupt on underflow.

Figure 48 shows a block diagram of the timer operating in mode 2. In this mode of operation, the timebase of the capture

timer is formed by counter 1, which counts down with the clock selected via the counter 1 clock selector. In Dual Input Cap-

ture mode, TAn and TBn pins function as capture inputs. A transition received on TAn pin causes a transfer of the timer

contents to TnCRA register. Similarly, a transition received on the TBn pin causes a transfer of the timer contents to TnCRB

register. TAn and TBn inputs can be configured to perform a counter preset to FFFF16 on reception of a valid capture event.

Reload A = Time 1

Timer/Counter 1

Reload B = Time 2

Timer 1

Clock

Underflow

TAn

TAIEN

TAPND

TnCNT1

TnCRA

TnCRB

TBIEN

TBPND

Timer

Interrupt 1

Timer

Interrupt 1

TAEN

Timer/Counter 2

TnCNT2

Timer 2

Clock TDIEN

TDPND

Timer

Interrupt 2

TBn

Clock

Selector

Underflow

Figure 47. Mode 1, PWM and Counter

Embedded Controller Modules (Continued)

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In this case, the current value of the counter is transferred to the corresponding capture register; following this, the counter

is preset to FFFF16. Using this approach enables an external signal’s on-time, off-time or period to be directly determined,

while reducing CPU overhead.

The pulse width of the input signal on TAn and TBn must be equal to or greater than one system clock cycle (see

Section 7.6.10 on page 399 for additional details). The values captured in TnCRA register at different times reflect the

elapsed time between transitions on the TAn pin. The same is true for TnCRB register and the TBn pin. Each input pin can

be configured to sense either rising or falling edge transitions.

The timer can be configured to generate interrupts on reception of a transition on either TAn or TBn. The interrupts can be

enabled or disabled separately for TAn or TBn by TAnIEN and TnBIEN bits. An underflow of TnCNT1 can also generate an

interrupt if the interrupt was enabled by TnCIEN bit. All three interrupts have individual pending flags. See Section 4.7.4 on

page 140 for detailed information.

Timer/counter 2 can be used as a “simple” system timer in this mode of operation. The TnCNT2 counter counts down with

the clock selected via the counter 2 clock selector, and TnCNT2 can be configured to generate an interrupt on underflow if

the interrupt was enabled by TnDIEN bit. See Section 4.7.4 on page 140 for detailed information.

Note that TnCNT1 cannot operate in the “Pulse Accumulate” or “External Event Counter” modes of operation since TBn input

is used as a capture input. Selecting either “Pulse Accumulate” mode or “External Event Counter” mode for TnCNT1 causes

TnCNT1 to stop. However, all available clock source modes may be selected for TnCNT2. Thus it is possible to use TnCNT2

to determine the number of capture events on TBn or the elapsed time between capture events on TBn.

Mode 3, Dual Independent Timer

Dual Independent Timer mode can be used for a wide variety of system tasks such as the generation of periodic system

interrupts, based either on the prescaled clock or external events on TBn. The timer can also toggle TAn pin on underflow,

allowing the simple generation of a processor-independent 50% duty cycle PWM signal on TAn. In this mode, TnCNT1

counts down and reloads from TnCRA on underflow while TnCNT2 is reloaded from TnCRB on underflow.

In this mode, the timer is configured to operate as a dual independent system timer or dual external event counter. In addi-

tion, timer/counter 1 can generate a 50% duty cycle PWM signal on the TAn pin. The TBn pin can be used as an external

event input or pulse accumulate input and forms the clock source to either counter 1 or counter 2, as described above. Both

counters can also be operated using the prescaled system clock. Figure 49 shows a block diagram of the timer in mode 3.

Capture A

Timer/Counter 1

Capture B

TnCNT1

TnCRA

TnCRB

Timer/Counter 2

TnCNT2

Timer1

Clock

Timer 2

Clock

TBn

TAn

TAIEN

TAPND

Timer

Interrupt 1

TBIEN

TBPND

Timer

Interrupt 1

TCIEN

TCPND

Timer

Interrupt 1

Underflow

TDIEN

TDPND

Timer

Interrupt 2

Underflow

TAEN

Preset

TBEN

Figure 48. Mode 2, Dual Input Capture

Embedded Controller Modules (Continued)

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Timer/counter 1 (TnCNT1) counts down at the rate of the selected clock (see “Counter Clock Source Select” on page 136

for additional details). On underflow, TnCNT1 is reloaded from TnCRA register and counting proceeds. If enabled, the TAn

pin toggles on underflow of TnCNT1. Software can select the initial value of TAn output as either high or low (see “Timer I/O

Functions” on page 141 for additional details). In addition, the TnAPND interrupt pending flag is set, and a timer interrupt 1

is generated if TnAIEN bit is set to 1 (see Section 4.7.4 on page 140 for detailed information). Since TAn toggles on every

underflow, a 50% duty cycle PWM signal can be generated on TAn without requiring interaction by the core.

Timer/counter 2 (TnCNT2) counts down at the rate of the selected clock (see “Counter Clock Source Select” on page 136

additional details). On every underflow of TnCNT2, the value contained in TnCRB register is loaded into TnCNT2, and count-

ing proceeds downwards from that value. In addition, the TnDPND interrupt pending flag is set, and a timer interrupt 2 is

generated if TnDIEN bit is set to 1. See Section 4.7.4 on page 140 for detailed information.

Mode 4, Input Capture and Timer

It is also possible to operate in a mode that offers a combination of a single timer, with automatic reload, and a single capture

timer. In this mode, TnCNT1 operates as a PWM-timer that is reloaded from TnCRA on underflow while TnCNT2 forms the

time base of the capture timer. The value on TnCNT2 is transferred to TnCRB when a valid event on TBn is detected. It is

possible to toggle TA on every underflow of TnCNT1 and thus generate a 50% duty cycle PWM signal on TAn.

This mode is a combination of modes 3 and 2. It allows timer/counter 2 to operate as a single-input capture timer concur-

rently with timer/counter 1. (Timer/counter 2 can be used as a system timer as described in mode 3.) Figure 50 shows a

block diagram of the timer in mode 4.

TnCNT1 starts counting down once a clock has been enabled. On underflow, TnCNT1 is reloaded from TnCRA register, and

counting proceeds downwards from that value. If enabled, the TAn pin toggles on every underflow of TnCNT1. Software can

select the initial value of TAn output signal as either high or low (see Section 4.7.5 on page 141 for additional details). In

addition, the TnAPND interrupt pending flag is set, and a timer interrupt 1 is generated if TnAIEN bit is set to 1 (see

Section 4.7.4 on page 140 for detailed information). Since TAn toggles on every underflow, a 50% duty cycle PWM signal

can be generated on TAn without requiring any interaction of software (and therefore the core).

TnCNT2 starts counting down once a clock has been enabled. When a transition is received on TBn, the value contained in

TnCNT2 is transferred to TnCRB, and the interrupt pending flag, TnBPND, is set. A timer interrupt 2 is generated if it is en-

abled. A preset of the counter to FFFF16 on detection of a transition on TBn can be enabled. In this case, the current value

of TnCNT2 is transferred to TnCRB, followed by a preset of the counter to FFFF16. TnCNT2 starts counting downwards from

FFFF16 until the next transition is received on TBn, which causes the procedure of capture and preset to be repeated. Un-

derflow of TnCNT2 sets the TnDPND interrupt pending flag and can also generate a timer interrupt 2 if the interrupt was

enabled (see Section 4.7.4 on page 140 for detailed information.). The input signal on TBn must have a pulse width equal

to or greater than one system clock cycle (see Section 7.6.10 on page 399 for additional details). TBn can be configured to

sense either rising or negative edge transitions.

Reload A

Timer/Counter 1

Reload B

Timer 1

Clock TA

TAIEN

TAPND

TnCNT1

TnCRA

TnCRB

TDIEN

TDPND

Timer

Interrupt 1

Timer

Interrupt 2

TAEN

Timer/Counter 2

TnCNT2

Timer 2

Clock

TBn

Clock

Selector

Underflow

Figure 49. Mode 3, Dual Independent Timer

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Note that TnCNT2 can not operate in the Pulse Accumulate or External Event Counter modes since TBn input is used as a

capture input. Selecting either Pulse Accumulate mode or External Event Counter mode for TnCNT2 causes TnCNT2 to stop.

Note, however, that all available clock source modes may be selected for TnCNT1. Thus it is possible to use TnCNT1 to

determine the number of capture events on TBn or the elapsed time between capture events on TBn.

4.7.4 Timer Interrupts

The MFT16 contains a total of four interrupt sources that are mapped to two different system interrupts. All sources have a

pending flag associated with them and can be enabled or disabled under software control. The pending flags are TnXPND,

where n is the module and X is a letter from A to D. An interrupt enable flag, TnXIEN, is associated with each interrupt pend-

ing flag. Interrupt sources A, B or C can generate a timer interrupt 1; interrupt source D can generate a timer interrupt 2.

Note that not all interrupt sources are available in all modes. Table 19 shows which events can trigger an interrupt in each

mode of operation:

Table 19. MFT16 Interrupts

System

Interrupt

Pending

Flag

Mode 1 Mode 2 Mode 3 Mode 4

PWM and Counter Dual Input Capture Dual Independent

Timer Input Capture and

Timer

Int. 1

TnAPND TnCNT1 reload from

TnCRA Input capture on TAn

transition TnCNT1 reload from

TnCRA TnCNT1 reload from

TnCRA

TnBPND TnCNT1 reload from

TnCRB Input Capture on TBn

transition N/A Input Capture on TBn

transition

TnCPND N/A TnCNT1 underﬂow N/A N/A

Tier

Int. 2 TnDPND TnCNT2 underﬂow TnCNT2 underﬂow TnCNT2 reload from

TnCRB TnCNT2 underﬂow

Reload A

Timer/Counter 1

Capture B

Timer 1

Clock TAn

TAIEN

TAPND

TnCNT1

TnCRA

TnCRB

Timer

Interrupt 1

TATEN

Timer/Counter 2

TnCNT2

Timer 2

Clock

Underflow

TDIEN

TDPND

Timer

Interrupt 2

TBIEN

TBPND

Timer

Interrupt 1

TBn

TBEN

Preset

Figure 50. Mode 4, Input Capture and Timer

Embedded Controller Modules (Continued)

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4.7.5 Timer I/O Functions

There are two I/O pins associated with each of the MFT16 modules: TAn and TBn, where n denotes the module on a given

device. The functionality of TA and TB depends on the mode of operation and the value of TAEN and TBEN bits. Table 20

shows the function of TA and TB versus the selected mode of operation. Note that if TA functions as a PWM output, the

initial and present value of TA is defined by TAOUT. For example, to start with TA high, TAOUT must be set (1) prior to

enabling the timer clock.

4.7.6 Operation in Development System

The MFT16 supports freezing the counters during breakpoints while operating in development systems. If FREEZE bit is

asserted, all timer counter clocks are inhibited, and the current values of timer/counter registers TnCNT1 and TnCNT2 are

frozen. Once FREEZE becomes inactive, counting resumes from the previous value. See 4.20.5 on page 273 for more de-

tails.

Table 20. MFT16 I/O Functions

I/O TnAEN

TnBEN

Mode 1 Mode 2 Mode 3 Mode 4

PWM and Counter Dual Input Capture Dual Independent

Timer Input Capture and

Timer

TAn

TnAEN=0

TnBEN=X No Output Capture TnCNT1

into TnCRA No Output toggle No Output toggle

TnAEN=1

TnBEN=X Toggle Output on

underﬂow of TnCNT1 Capture TnCNT1

into TnCRA and

preset TnCNT1 Toggle Output on

underﬂow of TnCNT1 Toggle Output on

underﬂow of TnCNT1

TBn

TnAEN=X

TnBEN=0 Ext. Event or Pulse

Accumulate Input Capture TnCNT1

into TnCRB Ext. Event or Pulse

Accumulate Input Capture TnCNT2

into TnCRB

TnAEN=X

TnBEN=1 Ext. Event or Pulse

Accumulate Input Capture TnCNT1

into TnCRB and

preset TnCNT1 Ext. Event or Pulse

Accumulate Input Capture TnCNT2

into TnCRB and

preset TnCNT2

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4.7.7 MFT16 Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

MFT16 Register Map

Timer/Counter Register 1 (TnCNT1)

The TnCNT1 register is a word-wide read/write register that is not altered by reset. The value on power-on is unknown.

Location: MFT16 1: 00 FD8016

MFT16 2: 00 FDA016

Type: R/W

Reload/Capture Register A (TnCRA)

The TnCRA register is a word-wide read/write register that is not affected by reset and thus contains random data on power-up.

Location: MFT16 1: 00 FD8216

MFT16 2: 00 FDA216

Type: R/W

Reload/Capture Register B (TnCRB)

The TnCRB register is a word-wide read/write register that is not affected by reset and thus contains random data on power-up.

Location: MFT16 1: 00 FD8416

MFT16 2: 00 FDA416

Type: R/W

Mnemonic Register Name Type

TnPRSC Clock Pre-Scaler Register R/W

TnCKC Clock Unit Control Register R/W

TnCNT1 Timer/Counter Register 1 R/W

TnCNT2 Timer/Counter Register 2 R/W

TnCRA Reload/Capture Register A R/W

TnCRB Reload/Capture Register B R/W

TnCTRL Timer Mode Control Register R/W

TnICTL Timer Interrupt Control Register R/W

TnICLR Timer Interrupt Clear Register WO

Bit 1514131211109876543210

Name TCNT1

Bit 1514131211109876543210

Name TCRA

Bit 1514131211109876543210

Name TCRB

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Timer/Counter Register 2 (TnCNT2)

The TnCNT2 register is a word-wide read/write register that is not altered by reset. The power-up value is unknown.

Location: MFT16 1: 00 FD8616

MFT16 2: 00 FDA616

Type: R/W

Clock Pre-Scaler Register (TnPRSC)

The TnPRSC register is a byte-wide read/write register. It contains the current value of the clock pre-scaler, CLKPS. The

Location: MFT16 1: 00 FD8816

MFT16 2: 00 FDA816

Type: R/W

Clock Unit Control Register (TnCKC)

The TnCKC register is a byte-wide read/write register. It defines the clock source selection for each timer counter. The reg-

ister is cleared on reset, thus disabling timer/counter 1 and timer/counter 2 clocks.

Location: MFT16 1: 00 FD8A16

MFT16 2: 00 FDAA16

Type: R/W

Bit 1514131211109876543210

Name TCNT2

Bit 76543210

Name Reserved CLKPS

Reset 00000000

Bit Description

4-0 CLKPS (Clock Pre-Scaler). The timer clock is generated by dividing the system clock by CLKPS+1. Therefore

the maximum timer clock frequency is equal to the system clock (CLKPS=00000) and the minimum timer clock

is the system clock divided by 32 (CLKPS=11111).

7-5 Reserved.

Bit 76543210

Name Reserved C2CSEL C1CSEL

Reset 00000000

Bit Description

2-0 C1CSEL (Counter 1 Clock Select). Deﬁnes the clock mode for timer/counter 1 where:

Bits

2 1 0 Description

0 0 0: No Clock (Counter 1 stopped)

0 0 1: Prescaled system clock

0 1 0: External Event on TBn

0 1 1: Pulse Accumulate

1 0 0: Slow-speed Clock

Other: Reserved

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Timer Mode Control Register (TnCTRL)

The TnCTRL register is a byte-wide read/write register. It defines the mode of operation of timer/counter and TAn and TBn

I/O pins. The register is cleared on reset.

Location: MFT16 1: 00 FD8C16

MFT16 2: 00 FDAC16

Type: R/W

5-3 C2CSEL (Counter 2 Clock Select). Deﬁnes the clock mode for timer/counter 2.

Bits

5 4 3 Description

0 0 0: No Clock (Counter 1 stopped)

0 0 1: Prescaled system clock

0 1 0: External Event on TBn

0 1 1: Pulse Accumulate

1 0 0: Slow-speed Clock

Other: Reserved

7-6 Reserved.

Bit 76543210

Name Reserved TAOUT TBEN TAEN TBEDG TAEDG MDSEL

Reset 00000000

Bit Description

1-0 MDSEL (Mode Select). Deﬁnes the MFT16 mode of operation.

Bits

1 0 Description

0 0: Mode 1

0 1: Mode 2

1 0: Mode 3

1 1: Mode 4

2TAEDG (TAn Edge Polarity).

0: A high-to-low transition on TAn causes the action defined by the mode of operation (e.g., input capture).

1: A low-to-high transition on TAn results in the defined action.

3TBEDG (TBn Edge Polarity).

0: A high-to-low transition on TBn causes the action defined by the mode of operation (e.g., input capture or ex-

ternal event count)

1: A low-to-high transition on TBn results in the defined action

In Pulse Accumulate mode, when this bit is set to 1, the count is enabled if TBn is high. When cleared (0) and

while operating in Pulse Accumulate mode, the counter is enabled if TBn is low.

4TAEN (TAn Enable). Enables TAn to function either as a preset input or as a PWM output, depending on the

mode of operation.

If this bit is set (1), while operating in Dual Input Capture mode (mode 2), a transition on TAn causes TnCNT1

to be preset to FFFF16. In the remaining modes of operation, setting TnAEN enables TAn to function as a PWM

output. See Table 20 on page 141 for additional information.

5TBEN (TBn Enable). When set (1), and while operating in either Dual Input Capture mode (mode 2) or Input

Capture and Timer mode (mode 4), a transition on TBn causes the corresponding timer/counter to be preset to

FFFF16. In mode 2, TnCNT1 is preset to FFFF16; in mode 4, TnCNT2 is preset to FFFF16. The bit has no

effect while operating in any mode other than modes 2 or 4. See Table 20 on page 141 for additional

information.

Bit Description

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Timer Interrupt Control Register (TnICTL)

The TnICTL register is a byte-wide read/write register. It contains the interrupt enable bit and associated interrupt pending

bits for the four timer interrupt sources. The TnICTL register format is shown below. The register is cleared on reset.

Location: MFT16 1: 00 FD8E16

MFT16 2: 00 FDAE16

Type: R/W

6TAOUT (TAn Output Data). Contains the value of TAn output when TAn is used as a PWM output.

0: TAn is low

1: TAn is high

This bit is set and cleared by hardware and thus reﬂects the status of TAn. This bit can be read at any time. It

may be used to set the initial value of TAn output in PWM mode. Note that if the hardware attempts to toggle

this bit at the same time as software is writing to the bit, the software write takes precedence over the hardware

update. This bit has no effect when TAn is used as input.

7Reserved.

Bit 76543210

Name TDIEN TCIEN TBIEN TAIEN TDPND TCPND TBPND TAPND

Reset 00000000

Bit Description

0TAPND (Timer Interrupt Source A Pending). When asserted, indicates that an interrupt condition (as shown

in Table 19 on page 140) has occurred. This bit can be set by either hardware or software.

This bit is cleared by a writing 1 to the respective bit in Timer Interrupt Clear register.

A write of 0 to this bit is ignored. The bit is cleared (0) on reset.

1Timer Interrupt Source B Pending (TBPND). Same as TAPND but for a different condition, as shown in

Table 19.

2Timer Interrupt Source C Pending (TCPND). Same as TAPND but for a different condition, as shown in

Table 19.

3Timer Interrupt Source D Pending (TDPND). Same as TAPND but for a different condition, as shown in

Table 19.

4TAIEN (Timer Interrupt A Enable).

0: No system interrupt occurs, but the associated pending flag TAPND is set

1: Enables a system interrupt based on the occurrence of a condition, as listed in Table 19

Note: The bit can be set or cleared by software at any time.

5TBIEN (Timer Interrupt B Enable).

0: No system interrupt occurs, but the associated pending flag TBPND is set

1: Enables a system interrupt based on the occurrence of a condition, as listed in Table 19

Note: The bit can be set or cleared by software at any time.

6TCIEN (Timer Interrupt C Enable).

0: No system interrupt occurs, but the associated pending flag TCPND is set

1: Enables a system interrupt based on the occurrence of a condition, as listed in Table 19

Note: The bit can be set or cleared by software at any time.

7TDIEN (Timer Interrupt D Enable).

0: No system interrupt occurs, but the associated pending flag TDPND is set

1: Enables a system interrupt based on the occurrence of a condition, as listed in Table 19

Note: The bit can be set or cleared by software at any time.

Bit Description

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Timer Interrupt Clear Register (TnICLR)

The TnICLR register is a byte-wide write-only register. It controls the clear of pending flags TAPND, TBPND, TCPND and

TDPND, which are located in TnICTRL register.

Location: MFT16 1: 00 FD9016

MFT16 2: 00 FDB016

Type: WO

Bit 76543210

Name Reserved TDCLR TCCLR TBCLR TACLR

Bit Description

0TACLR (Timer Pending A Clear). Writing a 1 to this bit clears the TAPND ﬂag in TnICTL register.

0: Has no effect on TAPND. The previous value of TAPND is maintained

1: Causes the TAPND flag to be cleared (0)

1TBCLR (Timer Pending B Clear). Writing a 1 to this bit clears the TBPND ﬂag in TnICTL register.

0: Has no effect on TBPND. The previous value of TBPND is maintained

1: Causes the TBPND flag to be cleared (0)

2TCCLR (Timer Pending C Clear). Writing a 1 to this bit clears the TCPND ﬂag in TnICTL register.

0: Has no effect on TCPND. The previous value of TCPND is maintained

1: Causes the TCPND flag to be cleared (0)

3TDCLR (Timer Pending D Clear). Writing a 1 to this bit clears the TDPND ﬂag in TnICTL register.

0: Has no effect on TDPND. The previous value of TDPND is maintained

1: Causes the TDPND flag to be cleared (0)

7-4 Reserved.

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4.8 PULSE WIDTH MODULATOR (PWM)

ThePWMmodulegenerates eight 8-bit PWM outputs; each may have a different duty cycle. A common 8-bit clock pre-scaler

and an 8-bit down-counter determine the cycle time, the minimal possible pulse width and the duty cycle steps.

4.8.1 Features

●Eight PWM outputs

●One 8-bit fully programmable pre-scaler

●One 8-bit fully programmable down-counter

●8-bit duty cycle control per output

●Programmable polarity per output

●Low Power mode

4.8.2 Functional Description

The PWM generates eight 8-bit PWM outputs, PWM0 to PWM7. The Duty Cycle registers 0 to 7 (DCRi, i = 0 to 7) control

the duty cycle of PWM0 to PWM7 output signals, respectively. The Cycle Time register (CTR) controls the cycle time and

duty cycle steps of all outputs.

The PWM use the core domain clock as a reference for its activities. The pre-scaler divider divides the PWM input clock by

a pre-programmable ratio of 1:1 through 1:256, as defined by the Clock Pre-Scaler register (PRSC).

The PWM cycle is defined in terms of cycles of the pre-scaler output clock. It has a period of (CTR +1) cycles, out of which

the signal will be high for DCRi cycles. INVPi, when set, may be used to inverse this behavior.

The cycle period is defined by the 8-bit down-counter. It counts using the output clock from the pre-scaler divider, starting

from the value held in CTR register down to 0. When it reaches 0, the down-counter restarts from the CTR value.

The DCRi register defines the number of clock cycles during which PWMi signal is high during the complete down-counter

cycle.

If Inverse PWMi bit (INVPi) in PWM Polarity register (PWMPOL) is active (1), the DCRi register defines the number of clock

cycles during which PWMi signal is low in each of the down-counter complete cycles.

Figure 51 is a functional block diagram of the PWM module.

Figure 51. PWM Block Diagram

8-Bit Pre-Scaler

Counter

Input

Clock 8-Bit

Down-Counter

Cycle Time

Duty Cycle

Compare

Duty Cycle

Compare

Clock Pre-Scaler

Down-Counter == CTR

Q Q

PWM0

Q Q

PWM7

INVPi INVPi

0 1 0 1

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4.8.3 Cycle Time and Duty Cycle Calculation

The PWM module supports duty cycles in the range of 0% to 100%.

The PWMi output signal cycle time is:

(PRSC + 1) x (CTR + 1) x TCLK

where:

●TCLK is the core domain clock cycle time (i.e., the PWM input clock).

●The cycle time may range from 2 x TCLK to 65536 x TCLK.

The PWMi output signal duty cycle (in %, when INVPi is 0) is:

(DCRi + 1) / (CTR + 1) x 100.

Special cases:

●If the DCRi value is greater than the CTR value, PWMi signal is always low.

●If DCRi value is equal to the CTR value, PWMi signal is always high.

When Inverse PWMi bit is 1, the value of PWMi output is inverted. i.e., in the period described as 1 is 0 and vice versa.

4.8.4 Power Modes

The PWM is in Low Power mode when Power Mode bit (PWR) in PWM Control Register (PWMCNT) is 0. In this mode, the

PWM input clock is disabled (stopped), but the registers are accessible and maintained. The PWMi signal is 0 when INVPi

bit is 0; it is 1 when INVPi bit is 1.

The PWM is in normal power mode when PWR bit in PWMCNT register is 1. In this mode, the PWM module is enabled, its

registers are accessible and its clock is functional.

The PRSC and CTR registers should be updated during Low Power mode. Otherwise, there may be unpredictable transient

behavior.

4.8.5 PWM Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

PWM Register Map

Clock Pre-Scaler Register (PRSC)

The PRSC register controls the cycle time and the minimal pulse width. PRSC is cleared (0016) on reset.

Location: 00 FD0016

Type: R/W

Mnemonic Register Name Type

PRSC Clock Pre-Scaler R/W

CTR Cycle Time R/W

DCRi Duty Cycle 0 to 7 R/W

PWMPOL PWM Polarity R/W

PWMCNT PWM Control R/W

Bit 76543210

Name PRSC7-0

Reset 00000000

Bit Description

7-0 Pre-Scaler Divider Value. The divider of the PWM input clock is the number deﬁned by PRSC7-0 + 1, e.g., a

value of 0016 results in a divide by 1, a value of FF16 results in a divide by 256.

The contents of this register may be changed only when the PWM module is in Low Power mode. Otherwise,

there may be unpredictable results.

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Cycle Time Register (CTR)

The CTR register controls the cycle time and duty cycle steps, CTR is set (FF16) on reset.

Location: 00 FD0216

Type: R/W

Duty Cycle Registers 0 to 7 (DCRi)

The DCRi (i = 0 to 7) registers control the duty cycle of PWMi output signal. DCRi is cleared (0016) on reset.

Location: Channel 0 - 00 FD0816

Channel 1 - 00 FD0A16

Channel 2 - 00 FD0C16

Channel 3 - 00 FD0E16

Channel 4 - 00 FD1016

Channel 5 - 00 FD1216

Channel 6 - 00 FD1416

Channel 7 - 00 FD1616

Type: R/W

Bit 76543210

Name CTR7-0

Reset 11111111

Bit Description

7-0 Cycle Time Value. The 8-bit down-counter divides the pre-scaler output clock by the number deﬁned by

CTR(7:0) + 1. For example, a value of 0016 results in a divide by 1, a value of FF16 results in a divide by 256.

The contents of this register may be changed only when the PWM module is in Low Power mode. Otherwise,

there may be unpredictable results.

Bit 76543210

Name DCRi7-0

Reset 00000000

Bit Description

7-0 Duty Cycle Value. DCRi register deﬁnes the number of clocks for which PWMi is high (from the full cycle of the

PWMi cycle), when Inverse PWMi bit in PWM Polarity register is 0.

If the DCRi value > CTR value, PWMi signal is always low.

If DCRi value == CTR value, PWMi signal is always high.

When Inverse PWMi bit is 1, the value of PWMi is inverse.

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PWM Polarity Register (PWMPOL)

This register controls the polarity of PWM0 to PWM7. The register is cleared (0016) on reset.

Location: 00 FD0416

Type: R/W

PWM Control Register (PWMCNT)

This register controls PWM operation. The register is cleared (0016) on reset.

Location: 00 FD0616

Type: R/W

Bit 76543210

Name INVP7-0

Reset 00000000

Bit Description

7-0 Inverse PWM Outputs. Each bit controls the corresponding polarity of PWM0 to PWM7; e.g., INVP0 controls

PWM0.

0: The number in DCRi indicates for how many clocks (of down-counter decrements) PWMi signal is high.

1: The number in DCRi indicates for how many clocks (of down-counter decrements) PWMi signal is low.

Bit 76543210

Name Reserved PWR

Reset 00000000

Bit Description

0Power Mode. This bit controls the operating mode of the PWM, as follows:

0: Low Power mode. PWM input clock is disabled (stopped). Its registers are accessible and maintained. PWMi

signal is 0 when INVPi bit is 0. PWMi signal is 1 when INVPi bit is 1.

1: Normal Power mode. PWM module is enabled. Its registers are accessible and its clock is functional.

7-1 Reserved.

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4.9 UNIVERSAL SYNCHRONOUS/ASYNCHRONOUS RECEIVER-TRANSMITTER (USART)

TheUSARTisafull-duplexsynchronous/asynchronousreceiver-transmitter that supports a wide range of software program-

mable baud rates and data formats. It handles automatic parity generation and several error detection schemes. DMA trans-

fers are supported to enable fast processor-independent receive and transmit.

4.9.1 Features

●Full duplex double-buffered receiver-transmitter

●Synchronous operation

●Asynchronous operation

●Programmable baud rate between CLK/2 and CLK/32768 baud

●Numerous framing formats

—seven, eight or nine data bits

—one or two stop bits

—odd, even, mark, space or no parity

●Hardware support of parity-bit generation during transmission and parity-bit check during reception

●Interrupt on transmit buffer empty, receive buffer full and receive error conditions with separate enable

●Software-controlled break transmission and detection

●Software-controlled reset, enable/disable

●Internal diagnostic capability

●Automatic error detection

—Parity Error

—Framing Error

—Data Overrun Error

●9-bit Attention mode

●DMA support for transmit and receive with separate enable

4.9.2 Functional Overview

The USART is composed of the following functional units:

●Transmitter

●Receiver

●Baud rate generator

●Control and error detection

Figure 52 shows a block diagram of the USART.

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Figure 52. USART Block Diagram

Each functional unit is described briefly in this section.

Transmitter

The Transmitter consists of an 8-bit transmit shift register and an 8-bit transmit buffer. Data is loaded in parallel from the

buffer into the shift register and then transmitted serially on the UTXD pin.

Receiver

The Receiver consists of an 8-bit receive shift register and an 8-bit receive buffer. Data is received serially into the shift reg-

ister from the URXD pin. After eight bits have been received, the contents of the shift register are transferred in parallel to

the receive buffer.

Baud Rate Generator

The Baud Rate Generator generates the clock for the Asynchronous and Synchronous modes of operation. It consists of

two registers and a two-stage counter. The registers are used to specify a pre-scaler value and baud rate divisor. The first

stage of the counter divides the CLK clock in 0.5 increments based on the value of the pre-scaler. The second stage of the

counter divides the output of the first stage in integer increments based on the value of the baud rate divisor.

Control and Error Detection

This unit contains the control registers (see Section 4.9.4 on page 158), control logic, error detection circuitry and parity gen-

erator/checker. It supports:

●Selection of the data format, mode of operation, clock source and parity type

●Generation and detection of parity

●Reporting of parity errors

●Detection and reporting of data overrun and frame errors

●Interrupts on transmit buffer empty, receive buffer full, receive error and delta clear to send conditions

●Generation and detection of line breaks

Peripheral Bus

sys_clk

Baud Clock

USCLK

UTXD

URXD

Transmitter

Receiver

Control and

Error Detection

Parity

Generator/Checker

Baud Rate

Generator

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4.9.3 Operation

The USART has two basic modes of operation; Synchronous and Asynchronous. In addition, two special Synchronous and

Asynchronous modes, attention and diagnostic, are available. This section describes the operating modes of the USART.

Asynchronous Mode

USARTAsynchronousmode enables the device to communicate with other devices using two communication signals: trans-

mit (UTXD) and receive (URXD).

In Asynchronous mode, Transmit Shift register (TSFT) and Transmit Buffer register (UTBUF) double buffer data for trans-

mission. To transmit a character, a data byte is loaded into UTBUF register. The data is then transferred to TSFT register.

While TSFT register is shifting out the current character (LSB first) on the UTXD pin, UTBUF register is loaded by software

with the next byte to be transmitted. When TSFT completes transmitting the last stop bit of the current frame, the contents

of UTBUF are transferred to TSFT register and the Transmit Buffer Empty flag (TBE) is set. The TBE flag is automatically

reset by the USART when the software loads a new character into UTBUF register. During transmission, the XMIP bit is set

high by the USART. This bit is reset only after the USART has sent the last stop bit of the current character and UTBUF

In Asynchronous mode, the input frequency to the USART is 16 times the baud rate, i.e., there are 16 clock cycles per bit

time. In Asynchronous mode, the baud rate generator is always used as the UART clock.

Receive Shift register (RSFT) and Receive Buffer register (URBUF) double buffer the data being received. The USART re-

ceiver continually monitors the signal on the URXD pin for a low level to detect the beginning of a start bit. On sensing this

low level, the USART waits for seven input clock cycles and samples again three times. If all three samples still indicate a

valid low, the receiver considers this to be a valid start bit, and the remaining bits in the character frame are each sampled

three times around the mid-bit position. For any bit following the start bit, the logic value is found by majority voting, i.e., the

two samples with the same value define the value of the data bit. Figure 53 illustrates the process of start-bit detection and

bit sampling. Serial data input on the URXD pin is shifted into RSFT register. On receiving the complete character, the con-

tents of RSFT register are copied into URBUF register and Receive Buffer Full flag (RBF) is set. The RBF flag is automati-

cally reset when software reads the character from URBUF register. The RSFT register is not user accessible.

Figure 53. USART Asynchronous Communication

Synchronous Mode

The USART Synchronous mode enables the device to communicate with other devices using three communication signals:

transmit (UTXD), receive (URXD) and clock (USCLK). In this mode, data bits are transferred synchronously using the

USART clock signal. As shown in Figure 54, the data is transmitted on the rising edge and received on the falling edge of

the clock. Data is transmitted and received with the LSB first.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 116

SampleSample

STARTBIT DATA (LSB)

Sample

DATABIT

12345678910111213141516

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Figure 54. USART Synchronous Communication

In Synchronous mode, Transmit Shift register (TSFT) and Transmit Buffer register (UTBUF) double buffer data for transmis-

sion. To transmit a character, a data byte is loaded into TBUF register. The data is then transferred to TSFT register. The

TSFT shifts out one bit of the current character, LSB first, on each rising edge of the clock. While the TSFT is shifting out

the current character on the UTXD pin, UTBUF register can be loaded by the software with the next byte to be transmitted.

When TSFT completes transmitting the last stop bit within the current frame, the contents of UTBUF are transferred to TSFT

register, and the Transmit Buffer Empty flag (TBE) is set. The TBE flag is automatically reset by the USART when the soft-

ware loads a new character into UTBUF register. During transmission, XMIP bit is set high by the USART. This bit is reset

only after the USART has sent the last frame bit of the current character and UTBUF register is empty.

Receive Shift register (RSFT) and Receive Buffer register (URBUF) double buffer the data being received. Serial data input

on the URXD pin is shifted into RSFT register at the first falling edge of the clock. Each subsequent falling edge of the clock

causes an additional bit to be shifted into RSFT register. The USART assumes a complete character has been received after

the correct number of rising edges on USCLK (based on the selected frame format) has been detected. On receiving a com-

plete character, the contents of RSFT register are copied into URBUF register, and Receive Buffer Full flag (RBF) is set.

The RBF flag is automatically reset when software reads the character from URBUF register.

The transmitter and receiver may be clocked from either an external source available on the USCLK pin or the internal baud

rate generator. If the internal baud rate generator is used, the baud clock is output on the USCLK pin.

Attention Mode

Attention mode is available for networking this device with other processors. This mode requires the 9-bit data format with

no parity. The number of start/stop bits are user selectable. In this mode, two types of 9-bit characters are sent on the net-

work: address characters consisting of eight address bits and a “1” (one) in the ninth bit position and data characters con-

sisting of eight data bits and a “0” (zero) in the ninth bit position.

While in Attention mode, the USART receiver monitors the communication flow but ignores all characters until an address

character is received. On the receipt of an address character, the contents of Receive Shift register are copied to the receive

buffer. The RBF flag is set and an interrupt (if enabled) is generated. The ATN bit is automatically reset to zero, and the

USART begins receiving all subsequent characters. The software must examine the contents of URBUF register and re-

spond by accepting the subsequent characters (by leaving the ATN bit reset) or waiting for the next address character (by

setting the ATN bit again).

The operation of the USART transmitter is not affected by the selection of this mode. The value of the ninth bit to be trans-

mitted is programed by setting the STPXB9 bit appropriately. The value of the ninth bit received is read from the RB9 bit.

Diagnostic Mode

This mode is available for diagnostic tests of the USART. In this mode, the UTXD and URXD pins are internally connected,

and data that is shifted out of Transmit Shift register is immediately transferred to Receive Shift register. This mode supports

only the 9-bit data format with no parity. The number of start and stop bits is user selectable.

Frame Format Selection

The format shown in Figure 55 consists of a start bit, seven data bits (excluding parity) and one or two stop bits. If parity bit

generation is enabled by setting the PEN bit, a parity bit is generated and transmitted following the seven data bits.

USCLK

UTXD

URXD

Sample Input

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Figure 55. Seven Data Bit Frame Options

The format shown in Figure 56 consists of one start bit, eight data bits (excluding parity) and one or two stop bits. If parity

bit generation is enabled by setting the PEN bit, a parity bit is generated and transmitted following the eight data bits.

Figure 56. Eight Data Bit Frame Options

The format shown in Figure 57 consists of one start bit, nine data bits and one or two stop bits. This format also supports

the USART attention feature. When operating in this format, all eight bits of UTBUF and URBUF are used for data. The ninth

data bit is transmitted and received using two bits in the control registers, called STPXB9 and RB9. Parity is not generated

or verified in this mode.

Figure 57. Nine Data Bit Frame Options

Baud Rate Generator

The Baud Rate Generator provides the basic baud clock from the system clock. The system clock is passed through a two-

stage divider chain consisting of a 5-bit baud rate pre-scaler (PSC) and an 11-bit baud rate divisor (DIV).

The correspondences between the 5-bit pre-scaler select (PSC) and pre-scaler factors are shown in Table 21.

1START

BIT 7-BIT DATA S

1a START

BIT 7-BIT DATA 2S

1c START

BIT 7-BIT DATA 2S

1b START

BIT 7-BIT DATA S

2START

BIT 8-BIT DATA S

2a START

BIT 8-BIT DATA 2S

2b START

BIT 8-BIT DATA S

2c START

BIT 8-BIT DATA 2S

3START

BIT 9-BIT DATA S

3a START

BIT 9-BIT DATA 2S

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A pre-scaler factor of zero corresponds to NO CLOCK. The NO CLOCK condition is the USART Power-Down mode. In this

mode, the USART clock is turned off in order to reduce power consumption. The user should set the pre-scaler factor to zero

(NO CLOCK) before selecting a new baud rate. Altering the baud rate while the USART is in operation could cause incorrect

data to be received or transmitted. UPSR register must contain a value other than zero when an external clock is used at

USCLK.

In Asynchronous mode, the baud rate is calculated by:

BR = SYS_CLK/(16 x N x P)

where:

●BR is the baud rate

●SYS_CLK is the system clock

●N is the value of the baud rate divisor + 1

●P is the pre-scaler divide factor selected by the value in the PSR register

The divide by 16 operation is performed because in Asynchronous mode, the input frequency to the USART is 16 times the

baud rate. In Synchronous mode, the input clock to the USART is equal to the baud rate.

Interrupts

The USART is capable of generating interrupts on one of the following conditions:

●Receive Buffer Full

●Receive Error

●Transmit Buffer Empty

Table 21. Pre-Scaler Factors

Pre-Scaler Select Pre-Scaler Factor Pre-Scaler Select Pre-Scaler Factor

00000 NO CLOCK 10000 8.5

00001 1 10001 9

00010 1.5 10010 9.5

00011 2 10011 10

00100 2.5 10100 10.5

00101 3 10101 11

00110 3.5 10110 11.5

00111 4 10111 12

01000 4.5 11000 12.5

01001 5 11001 13

01010 5.5 11010 13.5

01011 6 11011 14

01100 6.5 11100 14.5

01101 7 11101 15

01110 7.5 11110 15.5

01111 8 11111 16

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Figure 58 shows a diagram of the interrupt sources and associated enable bits.

The interrupts can be individually enabled or disabled using Enable Transmit Interrupt (ETI), Enable Receive Interrupt (ERI)

and Enable Receive Error Interrupt (EEI) bits in UICTRL register.

A transmit interrupt is generated when both the TBE and ETI bits are set. To remove this interrupt, the software must either

disable the interrupt by clearing the ETI bit or write to UTBUF register (thus clearing the TBE bit).

A receive interrupt is generated on two conditions:

●If both the RBF and ERI bits are set. To remove this interrupt, the software must either disable the interrupt, by clear-

ing the ERI bit, or read from URBUF register (thus clearing the RBF bit).

●If both the ERR and the EEI bits are set. To remove this interrupt, the software must either disable it by clearing the

EEI bit, or read USTAT register, which causes ERR ﬂag to be cleared.

DMA Support

The USART can operate with either one or two DMA channels. Two DMA channels are required for processor-independent

full-duplex operation. Both receive and transmit DMA can be enabled individually.

If the transmit DMA is enabled (ETD=1), the USART issues a DMA request every time the TBE flag is set. Enabling the

transmit DMA automatically disables the TX interrupt independent of the value of the ETI bit.

Enabling the receive DMA (ERD=1) causes a DMA request to be asserted every time the Receive Buffer Full flag (RBF) is

set. Once the receive DMA is enabled the RX interrupt is automatically disabled independent of the value of the ERI bit.

However, to detect errors during reception the receive error interrupt should be enabled (EEI=1) while using the DMA.

Break Generation and Detection

A line break is generated when BRK bit is set in MDSL register. The UTXD line remains low until the user resets the BRK bit.

A line break is detected if URXD remains low for a time equivalent to 10 bit times or longer, after a missing stop bit has been

detected.

Parity Generation and Detection

Parity is only generated or checked with 7- and 8-bit data formats. It is not generated or checked in Diagnostic Loopback

mode, Attention mode or in Normal mode with 9-bit data format. Parity generation and checking is enabled and disabled via

PEN bit in UFRS register. PSEL bits in UFRS register are used to select odd, even, mark or space parity.

ISE Mode Operation

The USART module supports breakpoint operation by preserving some of the status bits of the USTAT and UICTRL regis-

ters. While the FREEZE bit is asserted, the PE, FE, DOE, BKD and DCTS bits are not cleared on a read of STAT register.

EEI

ERI

ERR

RBF

DOE

PE RX

Interrupt

ETI

TBE TX

Interrupt

Figure 58. USART Interrupt Sources

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4.9.4 USART Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

USART Register Map

Receive Data Buffer Register (URBUF)

Location: 00 FD2216

Type: RO

Transmit Data Buffer Register (UTBUF)

Location: 00 FD2016

Type: R/W

Baud Rate Pre-Scaler Register (UPSR)

Byte-wide read/write register containing the 5-bit pre-scaler value in bit 7 (MSB) through bit 3 (LSB) and the upper three bits

of the baud divisor in bit 2 (MSB) through bit 0 (LSB). The register is cleared (0016) on reset.

Location: 00 FD2E16

Type: R/W

Baud Rate Divisor Register (UBAUD)

This byte-wide read/write register contains the lower eight bits of the baud rate divisor. The UPSR register contains the upper

three bits. The register is cleared (0016) on reset.

Location: 00 FD2C16

Type: R/W

Mnemonic Register Name Type

URBUF Receive Data Buffer Register RO

UTBUF Transmit Data Buffer Register R/W

UPSR Baud Rate Pre-Scaler Register R/W

UBAUD Baud Rate Divisor Register R/W

UFRS Frame Select Register R/W

UMDSL Mode Select Register R/W

USTAT Status Register RO

UICTRL Interrupt Control Register Varies per bit

Bit 76543210

Name URBUF

Bit 76543210

Name UTBUF

Bit 76543210

Name UPSC UDIV[10]: UDIV[8]

Reset 00000000

Bit 76543210

Name UDIV[7]: UDIV[0]

Reset 00000000

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Frame Select Register (UFRS)

This byte-wide read/write register controls the selection of the frame format, including number of data bits, number of stop

bits and parity. The register is cleared (0016) on reset.

Location: 00 FD2816

Type: R/W

Bit 76543210

Name Reserved PEN PSEL XB9 STP CHAR

Reset 00000000

Bit Description

1-0 CHAR. Selects the number of data bits per frame. Note that the parity bit is not included in the number of data

bits.

Bits

1 0 Description

0 0: Frame contains eight data bits

0 1: Frame contains seven data bits

1 0: Frame contains nine data bits

1 1: Loopback mode selected; frame contains nine data bits.

2STP. Programs the number of stop bits to be transmitted.

0: One stop bit transmitted

1: Two stop bits transmitted

3XB9. Contains the value of the 9th data bit for transmission only. The bit has no effect while operating with seven

or eight data bits per frame.

0: Transmit 0 as 9th data bit

1: Transmit 1 as 9th data bit

5-4 PSEL. Controls the mode of parity bit generation and checking. Note that while operating with nine data bits-

per-frame, the parity bit is omitted. In this case, the value of PSEL has no effect.

Bits

5 4 Description

0 0: Odd parity

0 1: Even parity

1 0: Mark (1)

1 1: Space (0)

6PEN. Enables or disables the generation of a parity bit generation and parity check. Note that there is no parity

bit while operating in the nine data bits-per-frame mode. In this case, this bit has no effect.

0: Parity disabled

1: Parity enabled

7Reserved.

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Mode Select Register (UMDSL)

This byte-wide read/write register controls the selection of the clock source, Synchronous mode, Attention mode and line

break generation. It contains the enable bits for the DMA channels. The register is cleared (0016) on reset.

Location: 00 FD2A16

Type: R/W

Bit 76543210

Name Reserved ERD ETD CKS BRK ATN MOD

Reset 00000000

Bit Description

0MOD. Selects the Synchronous or Asynchronous mode of operation:

0: Asynchronous mode

1: Synchronous mode

1ATN. Selects the Attention mode of operation. Cleared by hardware after reception of an address frame that is

a 9-bit character with a “1” in the ninth bit position.

0: Disable Attention mode

1: Enable Attention mode

2BRK. Setting the bit (1) causes UTXD to go low. UTXD remains low until the bit is cleared (0) by the user.

3CKS. Controls the source of the clock while operating in Synchronous mode (MOD=1).

0: USART operates from the baud rate generator and outputs the baud rate clock on USCLK

1: USART operates from an external clock provided on USCLK

While the USART is operated in Asynchronous mode (MOD=0), the bit has no effect.

4ETD.

0: No DMA request is asserted for transmit operations

1: DMA request is asserted when the Transmit Buffer Empty (TBE) flag is set (1)

5ERD.

0: No DMA request is asserted for receive operations

1: DMA request is asserted when the Receive Buffer Full (RBF) flag is set (1)

7-6 Reserved.

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Status Register (USTAT)

This byte-wide, read-only register contains the receive and transmit status bits. The register is cleared (0016) on reset.

Location: 00 FD2616

Type: RO

Bit 76543210

Name Reserved XMIP RB9 BKD ERR DOE FE PE

Reset 00000000

Bit Description

0PE. The bit is set when a parity error is detected within a received character. The bit is cleared by the hardware

when USTAT register is read.

0: No parity error detected

1: Parity error detected in a received byte since the last time USTAT was read

1FE. The bit is set when the USART fails to receive a valid stop bit at the end of a frame. Automatically cleared

on read of USTAT.

0: No framing error detected

1: Framing error detected on a received byte since the last time USTAT was read

2DOE. The bit is set when a new character is received and transferred to RBUF before the software has read the

previous character. Automatically cleared on read of the USTAT.

0: No data overrun error detected

1: Data overrun error detected since the last time USTAT was read

3ERR. The bit is set any time DOE, FE or PE is set. Automatically cleared if DOE, FE and PE are all zero. This

bit is read only. Any attempt to write to the bit by software does not alter its present value.

0: No DOE, FE or PE has occurred since the last time USTAT register was read.

1: A DOE, FE or PE error has occurred since the last time USTAT register was read.

4BKD. If set, indicates that a line break condition has occurred. A break condition is detected if RXD remains low

for a least ten bit times after a missing stop bit has been detected at the end of a frame. The bit is cleared under

the following conditions:

– On a read of USTAT register, if the break condition on RXD is no longer present. If RXD is still low when USTAT

– If the read of USTAT register did not cause the bit to be cleared because the break condition on RXD was still

in effect, the hardware clears the bit as soon as the break condition no longer exists, i.e., RXD returns to a high

level.

5RB9. Contains the ninth data bit of the last frame received when operating with the 9-bit data format.

0: “0” received in ninth bit position

1: “1” received in ninth bit position

6XMIP. Indicates that the USART is transmitting data. It is reset by hardware at the end of the last frame bit.

0: USART is not transmitting

1: USART is transmitting

7Reserved.

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Interrupt Control Register (UICTRL)

This byte-wide register contains the interrupt enable bits and the interrupt status flags. The register is set to 0116 on reset.

Location: 00 FD2416

Type: Varies per bit

4.9.5 Usage Hints

Calculating the Baud Rate in Asynchronous Mode

The equation for calculating the baud rate is:

BR = SYS_CLK/(16xNxP)

where:

●BR is the baud rate

●SYS_CLK is the system clock

●N is the value of the baud rate divisor + 1

●P is the pre-scaler divide factor selected by the value in the PSR register

Assuming a system clock of 5 MHz and a desired baud rate of 9600, the NxP term, according to the equation above, is:

NxP = (5x106)/(16x9600) = 32.552

The NxP term is then divided by each pre-scaler factor in Table 21 on page 156 to obtain a value closest to an integer. The

factor for this example is 6.5:

N = 32.552/6.5 = 5.008 (N = 5)

Bit 76543210

Name EEI ERI ETI Reserved RBF TBE

Reset 00000001

Bit Type Description

0ROTBE. The bit is set by the hardware when the USART transfers data from UTBUF register to TSFT

on reset.

0: Transmit buffer not empty

1: Transmit buffer empty

1RORBF. The bit is set by the hardware when the USART has received a complete data frame and

transferred the data from RSFT register to URBUF register. The bit is automatically cleared when

RBUF register is read.

0: Receive buffer not full. New data has not been transferred to RBUF since the last time it was read.

1: Receive buffer full. RBUF contains new data since the last time it was read.

4-2 Reserved.

5 R/W ETI. An interrupt is generated when the TBE ﬂag is set. Read/write bit.

0: Disable transmitter interrupt

1: Enable transmitter interrupt

6 R/W ERI. An RX interrupt is generated when the RBF ﬂag is set. Read/write bit.

0: Disable receiver interrupt

1: Enable receiver interrupt

7 R/W ETI. An RX interrupt is generated when the ERR ﬂag is set, indicating that a receive error has

occurred.

0: Disable receive error interrupt

1: Enable receive error interrupt

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The baud rate register is programed with a baud rate divisor of 4 (N = baud rate divisor +1). This produces a baud clock of:

BR = (5x106)/(16x5x6.5) = 9615.385

% error = (9615.385-9600)/9600 = 0.16

Note that the percent error is much lower than would be possible without the non-integer pre-scaler factor. Refer to the table

below for more examples.

Calculating the Baud Rate in Synchronous Mode

The equation for calculating the baud rate is:

BR = SYS_CLK/(2xNxP)

where:

●BR is the baud rate

●SYS_CLK is the system clock

●N is the value of the baud rate divisor + 1

●P is the pre-scaler divide factor selected by the value in the PSR register

The same procedure is used for determining the values of N and P, as in Asynchronous mode. However, non-integer pre-

scale values are not allowed.

System Clock Desired

Baud Rate N P Actual Baud Rate Percent Error

4 MHz 9600 2 13 9615.385 0.16

5 MHz 9600 5 6.5 9615.385 0.16

10 MHz 19200 5 6.5 19230.769 0.16

20 MHz 19200 5 13 19230.769 0.16

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4.10 TIMER AND WATCHDOG (TWD)

The Timer and WATCHDOG module (TWD) generates the clocks and interrupts used for timing periodic functions in the

system. It also provides WATCHDOG protection over software execution.

The TWD provides flexibility in system configuration by enabling the configuration of various clock ratios. After setting the

TWD configuration, the software can lock it to give a higher level of protection against erroneous software action. Once a

section of the TWD is locked, only reset releases it. See Figure 59 for the TWD block diagram.

4.10.1 Features

●32.768 KHz input clock

●Programmable pre-scale counter

●16-bit programmable periodic interrupt timer

●8-bit WATCHDOG counter

●WATCHDOG signal generation in response to failure detection, such as:

—WATCHDOG service performed too early

—WATCHDOG service performed too late

—Wrong DATA used in a service by data match

4.10.2 Functional Description

Input Clock

The TWD bases all its counting activities on a 32.768 KHz clock. The WATCHDOG can count using a division of the 32 KHz

clock (either T0OUT or T0IN).

(TWCP)

32.768 KHz

16-Bit Timer

5-Bit Pre-Scale

Counter

WATCHDOG

Peripheral Bus

T0OUT

WATCHDOG

T0IN

FREEZE

TWDT0 Register

WDCNT

WDSDM WATCHDOG

Service

Logic

Figure 59. Timer and WATCHDOG Block Diagram

from RTC

(DEV Env. only)

to ICU

WDCT0I bit (TWCFG Register)

T0IN

to ACM

Signal

to Reset Circuit

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Pre-Scale

A pre-scale counter divides the input clock (32.768 KHz) by a factor of 2MDIV. MDIV in TWCP register is in the range of 0

through 5 (i.e., divide ratio of 1:1 through 1:32). The pre-scaled output is used as an input clock for a 16-bit timer (TWDT0)

and is referred to as T0IN.

TWD Timer 0

TWD Timer 0 is a 16-bit, programmable, automatically re-triggered down-counter. It countson the rising edge ofT0IN.It starts

from the value loaded to TWDT0 register down to zero and then restarts counting from TWDT0 at the next T0IN cycle.

When the counter reaches 0, T0OUT is set (1) for one T0IN cycle. This makes the Timer 0 cycle:

(TWDT0 + 1) x T0IN-cycle.

T0OUT is input to the ICU and can be used as the time base for activities such as system tick.

When TWDT0 is loaded with a new value, the counter uses it the next time it restarts counting (i.e., after reaching zero). If

RST in Timer Control register (T0CSR) is written 1, the timer is restarted on the next rising edge of T0IN.

Notes:

●RST bit in T0CSR register is cleared after completing this load.

●When MDIV in TWCP register is 0, the timer counter may skip one count when loaded with a new value.

WATCHDOG Operation

The WATCHDOG is an 8-bit down counter, operating on the rising edge of its currently selected clock source. On reset, it

is disabled (i.e., it does not count and no WATCHDOG signal is generated). A write to the WATCHDOG Count register

(WDCNT) or the WATCHDOG Service Data Match (WDSDM) register either starts the counter or, if WATCHDOG is already

running, performs a restart (“touch”) operation. Once the WATCHDOG is counting down, only a reset can stop it.

Writing to WDCNT register is enabled while LWDCNT in TWCFG register is 0. A write to WDCNT starts the WATCHDOG,

and it begins counting down from the written value. If the service on data match is enabled (WDSDME in TWCFG register

is 1), writing to WDSDM register with 5C16 restarts the WATCHDOG counter from the value stored in WDCNT.

A WATCHDOG signal is triggered if one of the following occurs:

●The counter reaches zero (too late service).

●The WATCHDOG is written to more than once per WATCHDOG clock cycle for the currently selected clock (too early

service). Writing to the WATCHDOG more than once per three WATCHDOG clock cycles (for the currently selected

clock) may cause the WATCHDOG signal to trigger.

●Data other than 5C16 is written to WDSDM when WDSDME in TWCFG register is 1.

WATCHDOG Clock Source Selection

Select the clock source as follows:

●WDCT01 bit in TWCFG register is 0: T0OUT

●WDCT01 bit in TWCFG register is 1: T0IN

Changing the WATCHDOG clock source may cause it to gain or lose one clock cycle.

Notes:

●When MDIV in TWCP register is 0, the WATCHDOG counter may skip one count when loaded with a new value.

●After activating WATCHDOG, avoid entering Idle mode in the ﬁrst four low-frequency clock cycles.

TWD Control and Conﬁguration

The TWD Configuration register (TWCFG) allows you to:

●Set the WATCHDOG clock source: T0IN or T0OUT

●Enable WATCHDOG service on write to WDSDM register

●Deﬁne which of TWCFG, TWCPR, TWDT0, T0CSR and WDCNT is locked.

Once LTWCFG, LTWCP, LTWDT0 or LWDCNT, in TWCFG register, is set its respective resources are locked and can be

cleared only by reset. Setting any of these registers prevents runaway software from tampering with the respective WATCH-

DOG function.

Operation in Idle Mode

The TWD is active in Idle mode: the counters continue to function, and interrupts and error signals are issued.

Write operations to TWCP, TWDT0 and WDCNT may be delayed by up to three 32.768 KHz clock cycles. The software should

avoid entering Idle mode during this period. WDTLD bit in T0CSR register indicates when it is safe to switch power modes.

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4.10.3 TWD Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

TWD Register Map

Timer and WATCHDOG Conﬁguration Register (TWCFG)

The TWCFG register is a byte-wide, read/write register. It defines the WATCHDOG clock input and service method and en-

ables TWD control register locking. Setting the required configuration and locking the TWCFG stops the software from in-

terfering with the WATCHDOG operation. On reset, non-reserved bits of TWCFG are initialized to 0.

Location: 00 FEE016

Type: R/W

Mnemonic Register Name Type

TWCFG Timer and WATCHDOG Conﬁguration Register R/W

TWCP Timer and WATCHDOG Clock Pre-Scaler Register R/W

TWDT0 TWD Timer 0 Register R/W

T0CSR TWDT0 Control and Status Register R/W

WDCNT WATCHDOG Count Register WO

WDSDM WATCHDOG Service Data Match Register WO

Bit 76543210

Name Reserved WDSDME WDCT0I LWDCNT LTWDT0 LTWCP LTWCFG

Reset 00000000

Bit Description

0LTWCFG.

0: Enables read/write from/to TWCFG register

1: Any data written to it is ignored and reading from it returns unpredictable values

Once LTWCFG is set, it can only be cleared by reset.

1LTWCP.

0: Enables read/write from/to TWCP register

1: Any data written to it is ignored and reading from it returns unpredictable values

Once LTWCP is set, it can only be cleared by reset.

2LTWDT0.

0: Enables read/write from/to TWDT0 and T0CSR registers

1: Registers cannot be written to and TWDT0 cannot be read. Any data written to TWDT0 or T0CSR is ignored.

Reading from TWDT0 returns unpredictable values.

Once LTWDT0 is set, it can only be cleared by reset.

3LWDCNT.

0: Enables write to WDCNT register

1: Any data written to it is ignored and reading from it returns unpredictable values

Once LWDCNT is set, it can only be cleared by reset. When WDSDME bit is cleared, touch operations (i.e.,

writing to WDCNT register) may be performed when LWDCNT bit is either 0 or 1.

4WDCT0I.

0: Selects T0OUT clock as the WATCHDOG clock

1: Selects T0IN as the input clock

The hardware clock source selection overrides this clock selection.

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Timer and WATCHDOG Clock Pre-Scaler Register (TWCP)

The TWCP register is a byte-wide, read/write register. It defines the pre-scale ratio of the input clock and generates the T0IN

clock. On reset, the non-reserved bits of TWCP are initialized to 0.

Location: 00 FEE216

Type: R/W

TWD Timer 0 Register (TWDT0)

The TWDT0 register is a read/write register. It defines the T0OUT interrupt rate. On reset, this register is initialized to

FFFF16.

Location: 00 FEE416

Type: R/W

5WDSDME. Selects the WATCHDOG touch mechanism

0: Disables the WATCHDOG service using WDSDM register. In this case, the WATCHDOG should be serviced

by writing a value to WDCNT register. When this bit is cleared, write operations to WDSDM are ignored.

1: Selects the use of data match using the WDSDM mechanism.

7-6 Reserved.

Bit 76543210

Name Reserved MDIV

Reset 00000000

Bit Description

2-0 MDIV. Deﬁnes the pre-scale ratio of the input clock. The pre-scale ratio is 2MDIV. The value of MDIV must be in

the range of 0-5, providing a pre-scale ratio of 1 to 32.

MDIV allowed values:

Bits

2 1 0 Clock Ratio

0 0 0: 1:1

0 0 1: 1:2

0 1 0: 1:4

0 1 1: 1:8

1 0 0: 1:16

1 0 1: 1:32

Other Reserved

7-3 Reserved.

Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Name PRESET

Reset 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

Bit Description

15-0 PRESET. Deﬁnes the counter preset value. Whenever the counter reaches zero, it starts counting down from

this value. The T0OUT frequency is the T0IN frequency divided by (PRESET+1). The allowed values of the

PRESET ﬁeld are 000116 through FFFF16.

Bit Description

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PC87591E/S/L

TWDT0 Control and Status Register (T0CSR)

The T0CSR register is a read/write register. It controls the operation and provides the status of the T0 timer. The non-re-

served bits of T0CSR are cleared (0) on reset.

Location: 00 FEE616

Type: R/W

WATCHDOG Count Register (WDCNT)

The WDCNT register is a byte-wide, write-only register. It holds the value loaded into the WATCHDOG counter when it is

touched and counts down from it. The WATCHDOG is started by the first write to the register. Each successive write restarts

the WATCHDOG counter. A write to WDCNT functions as a touch operation when WDSDME bit TWCFG register is cleared,

even if WDCNT is locked; in this case, the WATCHDOG counter is restarted using the value loaded in PRESET field before

WDCNT was locked (i.e., the new PRESET value is ignored). On reset this register is initialized to 0F16.

Location: 00 FEE816

Type: WO

WATCHDOG Service Data Match Register (WDSDM)

The WDSDM register is a byte-wide, write-only register. When WDSDME in TWCFG register is set, the WATCHDOG count-

ing restarts from the value in WDCNT, when WDSDM is written with 5C16. If any other data is written to this register, it trig-

gers a WATCHDOG signal. If RSDATA is written more than once per three WATCHDOG clock cycles, a WATCHDOG signal

is also triggered. When the WDSDME bit is cleared, a write to this register is ignored.

Location: 00 FEEA16

Type: WO

Bit 76543210

Name Reserved WDLTD Reserved TC RST

Reset 00000000

Bit Description

0RST (Reset). When set (1), forces the timer to restart counting in the next input clock rising edge. The bit is

cleared by the input clock rising edge, indicating that the counter resumed its automatic re-triggerable operation.

Writing 0 to this bit is ignored.

1TC (Terminal Count). Indicates that the counter has reached zero (terminal count). This bit is cleared each time

the register is read. It is a read-only bit and data written to it is ignored.

2Reserved.

3WDLTD (WATCHDOG Last Touch Delay). The bit is set when the WDCNT is written. It is cleared after

WATCHDOG is updated. (After WATCHDOG is updated, it is safe to switch to Idle mode.)

7-4 Reserved.

Bit 76543210

Name PRESET

Reset 00001111

Bit Description

7-0 PRESET. Deﬁnes the counter preset value.

Bit 76543210

Name RSDATA

Bit Description

7-0 RSDATA.

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4.10.4 Usage Hints

The TWD protects WATCHDOG operation from software tampering. To achieve the highest level of protection, proceed as

follows:

1. Program the TWDT0 pre-scale and TMWT0 timers to the desired values.

2. Configure the WATCHDOG clock to use T0IN or T0OUT using WDCT0I bit in TWCFG register.

3. Program the WDCTL to the maximum period between WATCHDOG touch operations. Note that from this point, the

WATCHDOG starts operating and must be touched periodically to prevent a WATCHDOG error signal.

4. Configure the WATCHDOG to use data match, and lock all the TWD configuration and setting registers by setting bits 0

through 4 and bit 6 of the TWCFG.

5. Touch the WATCHDOG by writing 5C16 to WDSDM at the appropriate rate (i.e., no more than once every WATCHDOG

clock cycle and no less than the period programed to WDCTL).

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4.11 ANALOG TO DIGITAL CONVERTER (ADC)

The Analog to Digital Converter (ADC) monitors various voltages and temperatures in the system and reports their values

to the core.

The ADC can measure up to 10 external voltage inputs and four internal voltage sources, with 10-bit resolution. The internal

voltage sources measure the VDD,V

CC,AV

CC and VBAT supplies. VDD,V

CC and AVCC are divided by 2 to allow both over-

voltage and undervoltage detection. The external voltage inputs support thermistor-based temperature measurement.

The ADC can measure up to two, diode-based temperature sources with 1oC resolution. The current generated by the ADC

module causes a voltage drop on a remote (external) or local (internal) diode. This voltage is measured by the ADC and

converted to temperature units. An Overtemperature Shutdown (OTS) interrupt becomes active when the temperature of the

internal diode exceeds a programmable limit.

The ADC executes cycles of one temperature and three voltage measurements, each assigned to a separate output chan-

nel. The temperature channel measures the two temperature sources (remote and local) in consecutive cycles. Each of the

three voltage channels measures one selected voltage input during the cycle.

4.11.1 Features

●Voltage measurement

—Ten external voltage inputs and four internal power supply inputs

—10-bit resolution

—0 to 2.97V input voltage range

—High-impedance, ground-referenced inputs

—Enables thermistor-based temperature measurement

●Diode-based temperature measurement

—one remote (external) diode input and one local (internal) diode

—1oC/bit resolution

—−40oC to +125oC range (using the remote diode)

—Open/short detection for the remote diode connection

—Hardware-monitored, local overtemperature detection

●Internal high-precision reference

●Digital reading output channels

—Three voltage buffers and one temperature buffer (diode)

—Input selection for each voltage channel

●Sampling sequence and timing

—Three voltage and one temperature measurement within 100 ms.

—Cyclic measurement of the four output channels

—Separate enable for each channel

—Programmable conversion-start delay to guarantee input settling time

●Polling- or interrupt-driven interface

●Power consumption

—Zero current when disabled

—Low operating current

4.11.2 Functional Description

Inputs. The ADC has 16 inputs (AI0-13, AI15, AI16) divided in three groups:

●External Voltage (AI0-9). These are either general-purpose, positive DC voltage sources or temperature-dependent

voltage generated by using a Negative/Positive Temperature Coefﬁcient (NTC/PTC) thermistor in a resistive divider.

●Internal Voltage (AI10-13) These are internally connected to the supply voltages of the device (VDD,V

CC,AV

CC and

VBAT). Voltages higher than the full-scale voltage (VFS) are divided by 2, except for VBAT which is not divided in order

to minimize the current drain.

●Diode-Based Temperature Inputs (AI15, AI16). These are temperature-dependent voltage drops, on a remote and a

local diode, caused by the ﬂow of a current generated by the ADC. Since the AI8 and AI9 voltage inputs use the

same package pins as the remote diode (DP, DN), only one option (voltages or diode) is available at a time.

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Temperature Sensor Interface (TSI). The TSI generates the diode current and converts the voltage drop to a single-ended

voltage. In addition, the TSI of the remote diode enables open/short detection for the diode connection cable and sets the

corresponding status bits.

Analog Multiplexer. A 16 to 1 analog multiplexer selects one of the inputs for measurement by connecting it to the A/D con-

verter. Switching between inputs at different voltage levels requires delaying the conversion start until the input voltage to

the A/D converter has settled to the desired accuracy.

A/D Converter. The Σ−∆, high-resolution A/D converter receives the selected input and converts it. The result of the con-

version is either a 10-bit, unsigned integer digital value (0 to 1023) for voltage inputs or an 8-bit, 2s complement digital value

(−128 to +127) with the Least Significant Bit (LSB) having the value of 1°C for temperature inputs.

A high-precision internal reference generator sets the full-scale voltage value (VFS) of the A/D converter.

ADC Cycle. The ADC has four output “channels”: one for temperature and three for voltage measurement. The voltage

measurement channels are not related to specific inputs. They hold the input select control data for the next measurement

and contain a buffer in which the conversion result is stored. The temperature channel is slightly different, since it lacks the

input select control data. It “toggles” between the remote and local diode inputs, unless the remote diode input is disabled.

An ADC cycle includes measurements of all four channels and a calibration operation. The first measurement is of the tem-

perature channel, followed by a calibration measurement and the three voltage channels in ascending order, each for the

specific input number contained in its control register. The ADC waits for a programmable delay between the selection of an

input and the A/D conversion start that is necessary for A/D input settling to the required accuracy.

At the end of each A/D conversion, the result is stored in the corresponding buffer and a Data Valid (DATVAL) flag is set.

At the end of the ADC cycle, a flag is set indicating that all the channels contain new data. If enabled, an interrupt request

is sent to the core.

After reading the data at the end of the cycle, the software may choose to set up new values for the input select control data

inorderto measure different inputs during the following cycle. Another option is to use the old values for one or more voltage

channels and repeat the measurement on the previous inputs for a higher sampling rate. Any voltage output channel may

be disabled in order to skip its related measurement during the ADC cycle (shorter cycle).

Digital Comparator. A digital comparator checks the temperature measured by the local diode by comparing it with a user-

programmable limit. When the temperature of the PC87591x exceeds the Overtemperature Limit, the Overtemperature

Shutdown (OTS) signal becomes active and an interrupt request (if enabled) is sent to the core.

ADC Control/Status Registers and Data Out Buffers. These maybe read/writtenbythe corethrough thePeripheralbus.

Timing Control. This block reduces the frequency of the system clock to the lower value required by the ADC.

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Remote

Diode

AD0

Temp

Sensor

Interface

AI15

Temp

Sensor

Interface

AI16

AI0

AI1

AI2

AI3

AI4

AI5

AI6

AI7

AI8

AI9

AI10

AI11

AD9

AI12

AI13

VDD

VCC

VBAT

AVCC

16:1

Analog

MUX

A/D Converter

VREF

Voltage

Temperature

Channel

Channel 1

Channel 2

Channel 3

Voltage

Status and

Control

Limit

Overtemp

OTS

Timing

Control

Interrupt

System

ADC Clock

Delay

Peripheral Bus

AGND

AVCC

Analog

Power

3.3V

ADC

Clock

Σ−∆

Figure 60. ADC Functional Diagram

Local

Diode

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4.11.3 Voltage Measurement

The ADC performs a linear conversion of the input voltage signal to a 10-bit, unsigned digital representation. The input signal

should be applied relative to the AGND pin and should range from 0V to VFS (Full Scale).

The equations in the folowing table should be used to calculate the input voltage based on the reading from the Voltage

Channel Data result (VCHDAT field in VCHiDAT register).

An input signal of zero (ground) is converted to 00016; an input signal equal to (1023/1024) * VFS is converted to 3FF16.

Changing the input selection for a new measurement requires switching between inputs at different voltage levels. The input

interface circuits of the ADC, together with the externally added noise-rejection filters (if applicable), require a settling time

to reach the new voltage value with a 10-bit accuracy (less than 1/2 LSB error). Therefore, the ADC waits for a programma-

ble delay time between the selection of the input to be measured and the beginning of the A/D conversion. This Voltage

Channel Delay is expressed in ADC clock cycles in ADC Delay Control register (ADLYCTL). The number of ADC clock cy-

cles should be converted to time using the following formula:

tVD = Number_of_ADC_clocks *(System_clock_cycle) *SCLKDIV(5-0)

To calculate the required delay value according to externally added components, see Section 4.11.7 on page 185.

4.11.4 Temperature Measurement

TheADC performs a linear conversion of the temperature, measured by a remote or alocal diode, to an 8-bit, 2s complement

digital representation. The ADC generates a current that flows through the diode and measures the resulting voltage drop.

This differential voltage is converted to an 8-bit value, with the LSB equal to 1°C, according to Table 22.

Input Channel Scale Calculation1

1. See Section 7.4.1 on page 378 for the dynamic range relevant for each input.

AD0 to AD9 Low Vi = VCHDAT(9-0) * (1 / 1024) * VFSL

AD0 to AD9 High Vi = VCHDAT(9-0) * (1 / 1024) * VFSH

AD10 to AD13 Low2,3

2. High Scale is undeﬁned for these inputs.

3. These inputs are scaled down by 4 at the input and compensated back at the result read phase.

Vi = VCHDAT(9-0) * (1 / 1024) * VFSV

Table 22. Temperature Format Conversion

Temperature

(°C)

Temperature Channel Data

Binary Hex

+1271

1. Values higher than +125°C and lower than −40°C

are not within the speciﬁed operating temperature range.

0111 1111 7F16

+125 0111 1101 7D16

+100 0110 0100 6416

+40 0010 1000 2816

+25 0001 1001 1916

+1 0000 0001 0116

0 0000 0000 0016

−1 1111 1111 FF16

−25 1110 0111 E716

−40 1101 1000 D816

−12811000 0000 8016

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To change the diode selection for a new measurement, the input is switched between inputs at different voltage levels. The

temperature input interface circuits of the ADC require a settling time to reach the new voltage value with the equivalent of

1/2°C accuracy. Therefore, the ADC waits for a programmable delay time between the selection of the diode to be measured

and the beginning of the A/D conversion. This Temperature Channel Delay is expressed in ADC clock cycles in ADC Delay

Control register (ADLYCTL). The number of ADC clock cycles should be converted to time using the following formula:

Delay = Number_of_ADC_clocks *(System_clock_cycle) *SCLKDIV(5-0)

To calculate the required delay value according to the externally added components, see Section 4.11.7 on page 185.

4.11.5 ADC Operation

Reset

Section 3.2 on page 65 describes the types of PC87591x resets. The ADC is affected by the core domain reset events, as

described below:

All control, configuration and status registers are reset to their default values, as indicated in Section 4.11.6 on page 177.

An exception to this is OTSEV (Overtemperature Event) bit in ADCSTS register, which is reset at VCC Power-Up reset only.

The Temperature and Voltage (1, 2 and 3) Channel Data Buffer registers are not reset, since their value is undefined until

the ﬁrst measurement occurs (on each of them).

The ADC is disabled, with all interrupt sources masked and all event status bits reset. The remote temperature diode is dis-

abled, and the voltage inputs AD8 and AD9 may be used. The clock division factor, as well as the temperature channel delay

and the voltage channel delay, are all set to their maximum value (for the slowest ADC operation speed). The Overtemper-

ature limit is set to the highest value (127°C) for maximum flexibility. Each of the four channels is individually disabled, along

with its interrupt source. The Selected Input for all three voltage channels is set to 1F16 (disabled).

ADC Clock

The ADC clock is generated by dividing the system clock by a factor in the range of 4 to 63, as defined in SCLKDIV field in

ACLKCTL register (see Section 4.11.6 on page 177). The system clock’s source is the on-chip clock multiplier (see

Section 4.18 on page 239). The ADC clock needs to be at a frequency of 0.5 MHz. SCLKDIV must be programed prior to

enabling the ADC (i.e., while ADCEN of the ADCCNF register is 0).

Initializing the ADC

The ADC must be initialized before it is enabled. The following steps need to be taken to initialize it before enabling the ADC

(i.e., ADCEN bit in ADCCNF register is cleared):

●System Clock Division Factor - SCLKDIV ﬁeld in ACLKCTL register.

●Temperature Channel Delay - TMPDLY ﬁeld in ADLYCTL register.

●Voltage Channel Delay - VOLDLY ﬁeld in ADLYCTL register.

●Select use of Remote Diode or AI8 and AI9 - REMDEN bit in ADCCNF register.

●Copy calibration information from the ﬂash to the index-data ﬁelds using the following sequence:

a. Read a byte from ﬂash information block.

b. Set index for that parameter in ADCPINX register.

c. Write data to ADCPD register.

d. Repeat steps a-c for all parameters, as deﬁned in Section B.1 on page 434.

e. Select index 00h in ADCPINX and write data of 0116 to ADCPD to lock the calibration information.

Enabling and Disabling the ADC

Enabling the ADC. The ADC is enabled by setting ADCEN in ADCCNF register to 1.

After the ADC is enabled, its internal circuits need an activation delay of 100 µs. This activation delay should be added to

the ADC cycle until the first batch of measurements (after enabling the ADC) is available. Note that after activation, the first

set of results using the large scale mode (CSCALE bit in VCHiCTL register is clear) may be wrong.

The PC87591x temperature is measured as long as the ADC is active. Other measurement operations may be enabled or

disabled individually. When measurement conversions are enabled while the ADC is enabled, the measurement operations

start on the following conversion cycle.

Disabling the ADC. The ADC is disabled by resetting ADCEN in ADCCNF register when one of these conditions applies:

●VCC Power-Up reset

●Warm reset

●Core enters Idle mode

●The software resets the ADCEN bit.

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In this state, all ADC activities are halted and ADC current consumption from the AVCC is reduced. Note that re-enabling the

ADC causes an activation delay.

It is recommended to disable the ADC only after the buffer registers of all four channels have been read.

Interrupt Structure

The ADC Interrupt is a level high interrupt, generated if one (or more) of the events in Table 23 becomes active. The ADC

interrupt is connected to the ICU.

When an event flag and its related mask bit are set (enabled), the ADC Interrupt request is asserted. This is indicated by

a high level of the ADC Interrupt signal.

The software must reset the event flag (or reset its mask bit) in order to deassert the ADC Interrupt request.

All the interrupt mask bits (interrupt disabled), the data-related event flags (EOCEV and the four DATVAL bits) and the con-

nection-failure event flag (OPSHEV) are cleared by both reset conditions. The overtemperature event flag (OTSEV) is

cleared only by VCC Power-Up Reset.

The ADC Interrupt is routed to the ICU as an ADCI signal (see Section 4.3 on page 98).

ADC Operating Principles

Measurement Sequence. The following measurements are executed, in the order listed, during one ADC cycle for all en-

abled channels:

1. Temperature measurement, from the input indicated by SELIN field in TCHANCTL register. The A/D conversion starts

by selecting the input and waiting for the time period (TMPDLY delay) set in ADLYCTL register. The resulting 8-bit digital

value is stored in TCHANDAT register, and DATVAL bit in TCHANCTL register is set.

2. Voltage measurement for Voltage Channel 1, from the input selected by SELIN field in VCHN1CTL register. The A/D

conversion starts by selecting the input and waiting for the time period (VOLDLY delay) set in ADLYCTL register. The

resulting 10-bit digital value is stored in VCHN1DAT register, and DATVAL bit in VCHN1CTL register is set. Note: This

measurement is skipped if Voltage Channel 1 is disabled by setting the SELIN field in VCHN1CTL register to 1F16.

3. Voltage measurement for Voltage Channel 2, as above, using the VCHN2CTL and VCHN2DAT registers.

4. Voltage measurement for Voltage Channel 3, as above, using the VCHN3CTL and VCHN3DAT registers.

5. End of the ADC cycle. EOCEV bit in ADCSTS register is set (in addition to all the relevant DATVAL bits).

The software may read the measurement result for each channel immediately after its DATVAL bit is set. Alternatively, the

results may be read at the end of the cycle when EOCEV bit is set. After the data in VCHNiDAT register is read, the software

should clear the relevant DATVAL bit to indicate that the data in the buffers has been read.

The ADC cycle duration may be calculated using the formula below (N is the number of enabled voltage channels):

TADC cycle =2*(tTD +t

TC) + (N+1) *(tVD +t

VC)

Where:tTD - Temperature Conversion Delay Time

tTC - Temperature Conversion Time

tVD - Voltage Conversion Delay Time

tVC - Voltage Conversion time

Table 23. ADC Interrupt Structure

Event Flag Register

Mnemonic Mask Bit Register

Mnemonic Description

OPSHEV ADCSTS INTOSEN ADCCNF Open/Short Event/Enable

OTSEV ADCSTS INTOTEN ADCCNF Overtemperature Event/Enable

EOCEV ADCSTS INTECEN ADCCNF End-of-Cycle Event/Enable

DATVAL TCHANCTL INTDVEN TCHANCTL Data Valid Event/Enable (Temperature Channel)

DATVAL VCHN1CTL INTDVEN VCHN1CTL Data Valid Event/Enable (Voltage Channel 1)

DATVAL VCHN2CTL INTDVEN VCHN2CTL Data Valid Event/Enable (Voltage Channel 2)

DATVAL VCHN3CTL INTDVEN VCHN3CTL Data Valid Event/Enable (Voltage Channel 3)

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See Section 7.4 on page 378 for the values of tTC, Section 4.11.4 on page 173 for tTD calculation and Section Section 4.11.3

on page 173 for tVC calculation.

Temperature inputs from remote and local diodes are measured by alternating the remote and local diodes in each succes-

sive ADC cycle. If the remote diode measurement is disabled (RDMEASEN is set to 0 in TCHANCTL register or REMDEN

in ADCCNF register is set to 0), the local diode temperature is measured every ADC cycle.

Input Selection Field. Each Voltage Channel has its own programmable, input selection field (SELIN in VCHNxCTL regis-

ter). This field determines which input is measured by the channel during the current ADC cycle. The field also indicates to

which input the data in the channel buffer belongs. This field may be modified after the channel buffer has been read and

the DATVAL bit has been reset.

If the input selection field is not changed, the same input is measured during the next ADC cycle. This gives a sampling rate

of one TADC cycle for the specific input. If this field is changed and a different input is sampled, the sampling rate is lower for

each input, but the period for all scanned inputs is shorter.

Operation Sequence. After the ADC is properly initialized and enabled, one of the following example sequences can be used:

●EOCEV-driven ADC operation sequence for all temperature and voltage channels

●DATVAL-driven ADC operation sequence for one temperature or voltage channel

EOCEV-Driven ADC Operation Sequence for All Channels

1. When End-of-Cycle is reached (i.e., after all enabled channel conversions are completed), software can detect the event

by waiting for EOCEV bit in ADCSTS register to be set to 1.

2. Read the input number of the temperature channel by reading SELIN in TCHANCTL register.

3. Read the temperature value measured by reading TCHDAT in TCHANDAT register.

4. In preparation for the next measurement, clear DATVAL bit in TCHANCTL register by writing 1 to it.

5. Measure the input number for Voltage Channel 1 by reading SELIN in VCHN1CTL register.

6. Read the number of input measured in Voltage Channel 1 by reading VCHDAT in VCHN1DAT register.

7. In preparation for the next measurement (i.e., to define which input will be measured by Voltage Channel 1 during the

next ADC cycle), clear DATVAL bit in VCHN1CTL register by writing 1 to it (it may be the same input or, optionally, a different

one).

8. For Voltage Channel 2, repeat steps 5 through 7 for the VCHN2CTL and VCHN2DAT registers.

9. For Voltage Channel 3, repeat steps 5 through 7 for the VCHN3CTL and VCHN3DAT registers.

DATVAL-Driven ADC Operation Sequence for One Channel

1. Measure the end of channel by waiting for DATVAL in TCHANCTL or VCHNxCTL register to be set to 1.

2. Measure the input number by reading SELIN in TCHANCTL or VCHNxCTL register.

3. Read the measured data by reading TCHDAT or VCHDAT in TCHANDAT or VCHNxDAT register, respectively.

4. Optional (for voltage channels only): Change the input to be measured during the next ADC cycle: in VCHNxCTL regis-

ter, write a new SELIN value.

5. Prepare the temperature or voltage channel to receive new data: in TCHANCTL or VCHNxCTL register, write 1 to

DATVAL to clear it.

6. In preparation for the next measurement (i.e., to define which input will be measured by the temperature channel or the

voltage channel during the next ADC cycle), clear the DATVAL bit by writing 1 to it (it may be the same input or, option-

ally, a different one).

Reading Measurement Results

Polling-Driven Operation. Measurement results may be read by polling either EOCEV in ADCSTS register or each of the

four DATVAL bits in TCHANCTL register and three VCHNxCTL registers.

Polling EOCEV uses the sequence listed in “EOCEV-Driven ADC Operation Sequence for All Channels”, above. When

EOCEV is set, all four channels contain valid data and may be read.

Polling DATVAL uses the sequence listed in “DATVAL-Driven ADC Operation Sequence for One Channel”, above. When a

DATVAL bit is set, only its channel contains valid data that may be read. In this case, the EOCEV bit is redundant.

Interrupt-Driven Operation. The ADC may generate an interrupt to the core when any of the valid bits is set (EOCEV in

ADCSTSregisterorDATVAL in either TCHANCTL or any VCHNxCTL register). Theinterrupt is generated when the interrupt

enable bit for the respective status bit is set. The software in the interrupt routine should check the status bits as described

above for polling-driven operation to verify which of the DATVAL bits is set.

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An interrupt is expected from EOCEV when using the sequence listed in the EOCEV-driven ADC operation sequence (see

above). The EOCEV interrupt indicates that all four channels contain valid data and may be read. Interrupts from the

DATVAL bits should be disabled.

An interrupt is expected from one of the DATVAL bits when using the sequence listed in the DATVAL-driven ADC operation

sequence (see above). The DATVAL interrupt indicates that only its channel contains valid data that may be read. Interrupts

from the EOCEV bit should be disabled.

Failure Detection

Open/Short. At the beginning of the temperature measurement from the remote diode, the Temperature Sensor Interface

checks the condition of the interconnection (shorted or disconnected cable) and updates OPSHTYPE and OPSHEV in

ADCSTS register (see Section 4.11.6 on page 177). Although the measurement is executed and the DATVAL bit in

TCHANCTL register is set, the contents of the data buffer (TCHANDAT) should be ignored.

Overtemperature. At the end of the temperature measurement from the local diode (after DATVAL bit in TCHANCTL reg-

ister is set), the ADC compares the measured temperature with the limit value set by OTSLIM in TLOCOTL register. When-

ever the measured temperature is higher than the limit value, OTSEV in ADCSTS register is set and an active low OTS signal

is issued.

Overﬂow. An overflow occurs when DATVAL bit in TCHANCTL register is set at the end of a measurement, indicating that

the result of the previous measurement was not read. If an overflow occurs in at least one channel, the new measurement

result overrides the old data in the buffer, and OVFEV in ADCSTS register is set. This indicates that the result of the previous

measurement was lost.

4.11.6 ADC Registers

The ADC control/status and data out registers set interfaces with the core through the Peripheral bus. These registers are

mapped in the address space of the core, starting at the base address defined in Section B.1 on page 434.

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

ADC Register Map

The ADC register set contains seven common, control and status registers and eight channel-specific registers.

Table 24. ADC Register Map

Mnemonic Register Name Type

ADCSTS ADC Status Varies per bit

ADCCNF ADC Conﬁguration R/W

ACLKCTL ADC Clock Control R/W

ADLYCTL ADC Delay Control R/W

TLOCOTL Local Diode Overtemperature Limit R/W

ADCPINX ADC Parameters Index R/W

ADCPD ADC Parameters Data R/W

TCHANCTL Temperature Channel Control Varies per bit

TCHANDAT Temperature Channel Data Buffer RO

VCHN1CTL Voltage Channel 1 Control Varies per bit

VCHN1DAT Voltage Channel 1 Data Buffer RO

VCHN2CTL Voltage Channel 2 Control Varies per bit

VCHN2DAT Voltage Channel 2 Data Buffer RO

VCHN3CTL Voltage Channel 3 Control Varies per bit

VCHN3DAT Voltage Channel 3 Data Buffer RO

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ADC Status Register (ADCSTS)

This register indicates the global status of the ADC module. ADCSTS is cleared (0016)onV

CC Power-Up reset; on other

resets, bit 2 is unchanged and other bits are cleared.

Location: 00 FF2016

Type: Varies per bit

Bit 76543210

Name Reserved OPSHTYPE OPSHEV OTSEV OVFEV EOCEV

Warm Reset 00000-00

Power-Up

Reset 00000000

Bit Type Description

0ROEOCEV (End-of-Cycle Event). End of ADC cycle; all enabled measurements (up to four) are

completed. For each of the enabled channels, the DATVAL bit in the respective TCHANCTL VCHNxCTL

0: Cycle in progress (default)

1: End of ADC cycle (the bit remains set until all DATVAL bits in the Channel Control registers are reset)

1 R/W1C OVFEV (Data Overﬂow Event). Measurement data from the previous cycle was overwritten with data

from the current cycle before being read. In the event of a data overﬂow, the DATVAL bit remains set

and new data is placed in Channel Data Buffer register.

0: No overflow (default)

1: Overflow

2 R/W1C OTSEV (Overtemperature Signal Event). Temperature measured by local diode exceeded the limit.

0: Temperature below or equal to the limit (VCC Power-up reset default)

1: Temperature above limit (once set, this bit is cleared by writing 1 to it; writing 0 is ignored)

3 R/W1C OPSHEV (Open/Short Event). Remote diode connection failure (cable shorted or disconnected).

Checked before the beginning of the remote diode temperature measurement (if enabled, REMDEN in

ADCCNF register and RDMEASEN in TCHANCTL register are set to 1).

0: No fault was detected (default)

1: Connection failure - the cable was shorted or disconnected (once set, this bit is cleared by writing 1 to

it; writing 0 is ignored)

4ROOPSHTYPE (Open or Short Type). Remote diode connection failure type. Indicates the type of error

ﬂagged by OPSHEV.

0: DP shorted to DN or to AGND (default)

1: DP disconnected (floating) or shorted to AVCC

7-5 Reserved.

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ADC Conﬁguration Register (ADCCNF)

This register controls the operation and global configuration of the ADC module. ADCCNF is cleared (0016) on reset.

Location: 00 FF2216

Type: R/W

ADC Clock Control Register (ACLKCTL)

This register controls the system clock to ADC clock division. ACLKCTL is set to 3F16 on reset.

Location: 00 FF2416

Type: R/W

Bit 76543210

Name Reserved INTOSEN INTOTEN INTECEN REMDEN ADCEN

Reset 00000000

Bit Description

0ADCEN (ADC Module Enable). Controls the operation of the ADC to minimize power consumption and prevent

glitch effects during conﬁguration changes; see “Enabling and Disabling the ADC” on page 174.

0: ADC disabled (default)

1: ADC enabled

1REMDEN (Remote Temperature Diode Enable). Controls the utilization of the package pins for either the

remote diode (DP, DN) or the AI8 and AI9 voltage inputs (AD8, AD9).

0: AI8, AI9 voltage inputs enabled (default) - forces RDMEASEN in TCHANCTL register to 0; only the local diode

is measured by the temperature channel.

1: Remote diode enabled - if RDMEASEN in TCHANCTL register is set, the temperature channel measures both

the remote and the local diodes in successive cycles.

2INTECEN (Interrupt from End-of-Cycle Event Enable). Enables generation of an ADC interrupt on an End-of

ADC-cycle event (EOCEV in ADCSTS register).

0: Disabled (default)

1: Enabled - ADC Interrupt from EOCEV

3INTOTEN (Interrupt from Overtemperature Event Enable). Enables generation of an ADC interrupt on an

Overtemperature event (OTSEV in ADCSTS register).

0: Disabled (default)

1: Enabled - ADC Interrupt from OTSEV

4INTOSEN (Interrupt from Open/Short Event Enable). Enables generation of an ADC interrupt on an

Open/Short event (OPSHEV in ADCSTS register).

0: Disabled (default)

1: Enabled - ADC Interrupt from OPSHEV

7-5 Reserved.

Bit 76543210

Name Reserved SCLKDIV

Reset 00111111

Bit Description

5-0 SCLKDIV (System Clock Division Factor). Used to divide the system clock in order to obtain the ADC clock.

The system clock frequency is set separately (see Figure 78 on page 239). The resulting ADC clock frequency

should be equal to 0.5 MHz.

Range: 4 to 63 (default is 63, decimal values); values 0 to 3 are illegal and may result in undetermined ADC behavior.

7-6 Reserved.

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ADC Delay Control Register (ADLYCTL)

This register controls the delay between “input switching” and “conversion start” for the voltage and temperature channels.

ADLYCTL is set to A716 on reset.

Location: 00 FF2616

Type: R/W

Bit 76543210

Name TMPDLY Reserved VOLDLY

Reset 10100111

Bit Description

2-0 VOLDLY (Voltage Channel Delay). Compensates for the settling time of the input interface and externally added

ﬁlter (if used). The conversion of the VOLDLY value to delay, in terms of ADC clock cycles, is shown below. To

calculate the required value and the resulting delay time, see Section 4.11.3 on page 173 and “Calculating the

Voltage Channel Delay” on page 186.

VOLDLY Value

Bits

2 1 0: Voltage Channel Delay (ADC Clock Cycles)

0 0 1: 4

0 1 0: 8

0 1 1: 16

1 0 0: 32

1 0 1: 64

1 1 0: 128

1 1 1: 256 (default)

Other: Reserved

3Reserved.

7-4 TMPDLY (Temperature Channel Delay). Compensates for the settling time of the input interface and externally

added ﬁlter (if used). The conversion of the TMPDLY value to delay, in terms of ADC clock cycles, is shown

below. To calculate the required value and the resulting delay time, see Section 4.11.4 on page 173 and

“Calculating the Temperature Channel Delay” on page 188.

TMPDLY Value

Bits

7 6 5 4 Temperature Channel Delay (ADC Clock Cycles)

0 0 0 1: 32

0 0 1 0: 64

0 0 1 1: 128

0 1 0 0: 256

0 1 0 1: 512

0 1 1 0: 1024

0 1 1 1: 2048

1 0 0 0: 4096

1 0 0 1: 8192

1 0 1 0: 16384 (default)

Other: Reserved

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Local Diode Overtemperature Limit Register (TLOCOTL)

This register holds the limit value used for overtemperature detection. TLOCOTL is set to 7F16 on reset.

Location: 00 FF2816

Type: R/W

ADC Parameters Index Register (ADCPINX)

This register holds an index to the ADC parameters registers. Use it while initializing the ADC (see “Initializing the ADC” on

page 174 for more details). ADCPINX is cleared (0016) on reset.

Location: 00 FF2A16

Type: R/W

ADC Parameters Data Register (ADCPD)

This register enables access to the ADC parameters registers. Use it while initializing the ADC (see “Initializing the ADC” on

page 174 for more details).

Location: 00 FF2C16

Type: R/W

Bit 76543210

Name OTSLIM

Reset 01111111

Bit Description

7-0 OTSLIM (Overtemperature Limit Value). Threshold value for Overtemperature Event detection. Whenever the

temperature measured by the local (internal) diode exceeds this limit, the OTSEV bit is set, an interrupt is sent

to the core (if INTOTEN in ADCCNF register is set to 1) and the OTS signal becomes active. To calculate the

required value for a speciﬁc temperature limit, see Section 4.11.4 on page 173.

Range: −128 to +127 (default is +127; these are decimal values); 8-bit, 2s complement value with 1 LSB = 1oC.

Bit 76543210

Name Index

Reset 00000000

Bit Description

7-0 Index. Deﬁnes which parameter register is being accessed by the ADCPD register.

Bit 1514131211109876543210

Name Parameter Data

Bit Description

15-0 Parameter Data. The register is used to access the ADC parameters register that the Index register (ADCPINX)

points to.

Writing 0116 to index 0016 locks the parameter data registers from any further writes until the next reset.

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Temperature Channel Control Register (TCHANCTL)

This register both controls the operation and indicates the status of the Temperature channel. TCHANCTL is set to 1016 on

reset.

Location: 00 FF3016

Type: Varies per bit

Temperature Channel Data Buffer (TCHANDAT)

This register (buffer) holds the data measured by the Temperature Channel.

Location: 00 FF3216

Type: RO

Bit 76543210

Name DATVAL RDMEASEN INTDVEN SELIN

Reset 00010000

Bit Type Description

4-0 RO SELIN (Selected Input). Indicates which temperature input was selected for measurement. If

RDMEASEN is set to 0, only the value 16 dec is read.

Bits

4 3 2 1 0 Description

0 1 1 1 1: Remote diode (DP, DN pins) selected

1 0 0 0 0: Local diode (internal) selected (default)

5 R/W INTDVEN (Interrupt from Data Valid Enable). Temperature channel, Data Valid event (End-of-

conversion) enabled to the ADC Interrupt.

0: Disabled (default)

1: Enabled - ADC Interrupt from local DATVAL

6 R/W RDMEASEN (Remote Diode Measurement Enable). Enables the temperature measurement using the

remote diode (REMDEN in ADCCNF register is set to 1). Using only the local diode enables a higher

measurement rate for the internal temperature. The temperature channel cannot be disabled

(“skipped”) since the internal temperature measurement is required.

0: Measurement disabled - only the local diode is measured by the temperature channel; forced into this

state when REMDEN in ADCCNF register is set to 0 (default).

1: Measurement enabled - the temperature channel measures both the remote and the local diodes in

successive cycles; possible only if REMDEN is set to 1.

7 R/W1C DATVAL (Data Valid). The Temperature Channel Data Buffer contains new data. The data may be read

immediately or at the end-of-cycle. This ﬂag is cleared when the ADC module is disabled (ADCEN in

ADCCNF register is cleared) or by writing 1 to it.

0: No valid data in TCHANDAT register (default)

1: End of conversion - new data is available in TCHANDAT

Bit 76543210

Name TCHDAT

Bit Description

7-0 TCHDAT (Temperature Channel Data). Temperature of either the remote or local diode, measured by the

Temperature Channel. For the temperature word format, see Section 4.11.4 on page 173. The data is valid and

may be read only at the end of the conversion, when DATVAL in TCHANCTL register is set to 1. DATVAL must

be reset after reading the data.

Range: −128 to +127 (values are decimal); 8-bit, 2s complement value with 1 LSB = 1oC (the value at reset is

undeﬁned).

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Voltage Channel 1 Control Register (VCHN1CTL)

This register both controls the operation and indicates the status of Voltage Channel 1. VCHN1CTL is set to 1F16 on reset.

Location: 00 FF3416

Type: Varies per bit

Bit 76543210

Name DATVAL CSCALE INTDVEN SELIN

Reset 00011111

Bit Type Description

4-0 R/W SELIN (Selected Input). Selects a voltage input to be measured during the next ADC cycle. The new

value should be set before the beginning of the channel measurement. When read, this ﬁeld indicates

to which input the contents of the channel data buffer belongs. When written, it selects a new input for

the next channel measurement. See Figure 60 on page 172 for details on the channel input signals

connection to pins.

The channel is disabled by setting this ﬁeld to 111112. When disabled, the channel is “skipped”,

enabling a higher measurement rate for the remaining channels (shorter ADC cycle). The DATVAL bit

is cleared

Bits

4 3 2 1 0 Description

0 0 0 0 0: Channel 0

0 0 0 0 1: Channel 1

....

0 1 0 0 0: Channel 8 (Available when REMDEN bit in ADCCNF register is cleared)

0 1 0 0 1: Channel 9 (Available when REMDEN bit in ADCCNF register is cleared)

0 1 0 1 0: Channel 10

....

0 1 1 0 1: Channel 13

Other: Reserved

1 1 1 1 1: Channel Disabled (default)

5 R/W INTDVEN (Interrupt from Data Valid Enable). Enables generation of an ADC interrupt on a Voltage

Channel 1, Data Valid event (End-of-conversion).

0: Disabled (default)

1: Enabled - ADC Interrupt from local DATVAL

6 R/W CSCALE (Channel Scale). Controls the input scale of the input for the channel to be converted (as

selected by SELIN ﬁeld).

0: Channel uses the high range scale (default)

1: Channel uses the low range scale

7 R/W1C DATVAL (Data Valid). Voltage Channel 1 Data Buffer contains new data. The data may be read

immediately or at the end-of-cycle. This ﬂag is cleared when the channel is disabled, when the ADC

module is disabled (ADCEN in ADCCNF register is cleared) or by a write of 1 to it.

0: No new valid data in VCHN1DAT register (default)

1: End of conversion - new data is available in the buffer

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Voltage Channel 1 Data Buffer (VCHN1DAT)

This register (buffer) holds the data measured by Voltage Channel 1.

Location: 00 FF3616

Type: RO

Voltage Channel 2 Control Register (VCHN2CTL)

This register controls the operation and indicates the status of Voltage Channel 2. VCHN2CTL is set to 1F16 on reset.

Location: 00 FF3816

Type: Varies per bit

Voltage Channel 2 Data Buffer (VCHN2DAT)

This register (buffer) holds the data measured by the Voltage Channel 2.

Location: 00 FF3A16

Type: RO

Bit 1514131211109876543210

Name Reserved VCHDAT

Bit Description

9-0 VCHDAT (Voltage Channel 1 Data). Selected input voltage data, measured by Voltage Channel 1. To calculate

the voltage, see Section 4.11.3 on page 173. VCHN1DAT holds valid result when DATVAL bit in VCHN1CTL

Range: 0 to 1023 (0 to VFS); 10-bit, unsigned value with 1 LSB = VFS/1024 (the value at reset is undeﬁned).

15-10 Reserved.

Bit 76543210

Name DATVAL CSCALE INTDVEN SELIN

Reset 00011111

Bit Type Description

4-0 R/W SELIN (Selected Input). Same as Voltage Channel 1.

5 R/W INTDVEN (Interrupt from Data Valid Enable). Same as Voltage Channel 1.

6 R/W CSCALE (Channel Scale). Same as Voltage Channel 1.

7 R/W1C DATVAL (Data Valid). Same as Voltage Channel 1.

Bit 1514131211109876543210

Name Reserved VCHDAT

Bit Description

9-0 VCHDAT (Voltage Channel 2 Data). Same as Voltage Channel 1.

15-10 Reserved.

Embedded Controller Modules (Continued)

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Voltage Channel 3 Control Register (VCHN3CTL)

This register controls the operation and indicates the status of Voltage Channel 3. VCHN3CTL is set to 1F16 on reset.

Location: 00 FF3C16

Type: Varies per bit

Voltage Channel 3 Data Buffer (VCHN3DAT)

This register (buffer) holds the data measured by Voltage Channel 3.

Location: 00 FF3E16

Type: RO

4.11.7 Usage Hints

Power Supply and Layout Guidelines

For more information, see Section 3.1.3 on page 63.

Power Consumption

ADC power consumption from the analog supply (AVCC) is practically zero if the ADC is disabled by setting ADCEN in

ADCCNF register to 0.

When the ADC is enabled, the current consumption depends on the channel type measured (voltage or temperature) and

the ADC clock frequency. To minimize current consumption, disable the ADC when not in use. See details in “Enabling and

Disabling the ADC” on page 174.

Back-Drive Protection

To maintain the high performance of the analog circuits, AD(0-7), AD8/DP and AD9/DN pins are not back-drive protected.

Therefore, the voltage applied to these pins must be within the AGND to AVCC range; otherwise, the device may be dam-

aged. External circuits should not drive currents into these pins when the PC87591x is not powered up.

Measuring Out of Range Voltages

The ADC is capable of measuring positive input voltages from 0V to VFS. Input voltages outside this range should either be

divided or level-shifted, as required.

Bit 76543210

Name DATVAL CSCALE INTDVEN SELIN

Reset 00011111

Bit Type Description

4-0 R/W SELIN (Selected Input). Same as Voltage Channel 1.

5 R/W INTDVEN (Interrupt from Data Valid Enable). Same as Voltage Channel 1.

6 R/W CSCALE (Channel Scale). Same as Voltage Channel 1.

7 R/W1C DATVAL (Data Valid). Same as Voltage Channel 1.

Bit 1514131211109876543210

Name Reserved VCHDAT

Bit Description

9-0 VCHDAT (Voltage Channel 3 Data). Same as Voltage Channel 1.

15-10 Reserved.

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For positive input voltages higher than VFS, a resistor divider should be used in front of the analog input (see Figure 61a).

The divider should be calculated so that its output is lower than the full-scale value (VFS) for the maximum input signal

voltage.

For negative input voltages, a resistive level-shifter should be used in front of the analog input (see Figure 61b). The level-

shifter should be calculated so that its output is higher than 0V for the minimum input signal voltage.

Filtering the Noise on Voltage Input Signals

Noise may be coupled to the input signal for various reasons, including close proximity to digital circuits. The slow change

rate of the input signals, makes it possible to use an external low pass filter (LPF). This can be implemented by placing a

capacitor (CF) between the divider output and AGND, as shown in Figure 61. The cutoff frequency of this LPF should be at

least 22 times the maximum signal frequency required to be measured with a 10-bit accuracy (a smaller capacitor may be

used when a lower accuracy is acceptable). The formula below demonstrates the calculation of the components.

f(-3dB) =1/(2*π*Req*CF)

where: Req = (R1*

R2) / (R1 + R2)

Calculating the Voltage Channel Delay

The Voltage measurement delay time (tVD) is the period between input selection and the A/D conversion start. This delay

should be long enough to guarantee the voltage settling at the input of the A/D converter to within 1/2 LSB. This includes

the input interface circuits of the ADC and the externally added noise-rejection filters (if applicable). Figure 62 shows the

equivalent R-C circuit of a filtered input. Req represents the equivalent resistance of the input divider or level-shifter (see the

preceding section, “Filtering the Noise on Voltage Input Signals”). CFis the filter capacitor. The Input Interface Circuit in-

cludes the input the multiplexer.

Since the R-C of the input circuit is short, typically, all that is required is a very short delay, which shortens the overall mea-

surement time. The delay length may be sized during development by increasing the delay time from the minimum value to

the point were the ADC readout is not affected by the delay value (i.e., use the minimal delay to which the ADC readout is

invariant).

Thermistor-Based Temperature Measurement

The ADC is capable of measuring temperature by means of NTC or PTC thermistor devices. These elements change their

resistance according to their temperature. The resistance change is converted to voltage by connecting the element in a

voltage divider between AVCC and AGND, as shown in Figure 63. The translation of voltage to temperature is determined

by the parameters of the NTC/PTC thermistor in use.

VIN (12V)

ADn

VIN (-12V)

AVCC

AGND AGND

Figure 61. Measurement of Positive and Negative Voltages

a. VIN > VFS b. VIN < 0

Input

Signal

Figure 62. Filtered Voltage Input Equivalent Circuit

Interface

ADn

Circuit

Req

VIN CF

Input A/D Converter

Σ−∆

Embedded Controller Modules (Continued)

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Remote Diode Selection

Temperature accuracy depends on a good quality transistor used as a diode-connected, small-signal transistor. Accuracy

has been experimentally verified for the devices, among them Motorola, listed in Table 25. A temperature sensor can directly

measure the die temperature of CPUs with on-board temperature-sensing diodes.

The transistor must be a small-signal type with a relatively high forward voltage; otherwise, the A/D input voltage range might

be violated. The forward voltage must be greater than 0.25V at 10 µA for the highest expected temperature. The forward

voltage must be less than 0.95V at 100 µA for the lowest expected temperature. Large power transistors do not work. Also,

ensure that the base resistance is less than 100Ω. Tight specifications for forward-current gain (+50 to +150, for example)

indicate devices with consistent VBE characteristics.

Thermal mass can seriously degrade the temperature sensor’s effective accuracy. The use of smaller packages for remote

sensors, such as SOT23s, improves the situation.

Table 25. Remote Sensor Transistor Manufacturers

Filtering the Noise on Temperature Input Signals

Noise may be coupled to the input signal for various reasons, including close proximity to digital circuits. The ADC conver-

sion technology has good noise rejection especially for low-frequency signals, such as power supply hum. Rejection of high-

frequency noise can be improved using an external filter capacitor and PC board layout.

High-frequency noise is best filtered by placing a capacitor (CCof 2.2 nF) between pins DP and DN (see Figure 64), in prox-

imity to the PC87591x pins. The connection to the diode should use a twisted wire pair or a PCB that is read out using the

guidelines below.

It is most important to prevent any leak to ground, especially from the DP pin and serial resistance on the current loop to the

diode.

Manufacturer Model

Central Semiconductor (USA) CMPT3904

Motorola (USA) MMBT3904

National Semiconductor (USA) MMBT3904

Rohm Semiconductor (Japan) SST3904

Samsung (Korea) KST3904-TF

Siemens (Germany) SMBT3904

Zetex (England) FMMT3904CT-ND

NTC ADn

AVCC

AGND

Figure 63. Measuring Temperature Using Thermistors

a. NTC Thermistor b. PTC Thermistor

AVCC

PTC

ADn

AGND

Thermistor

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Calculating the Temperature Channel Delay

The delay time is the period between diode selection and the A/D conversion start. Due to the switched diode current, this

delay should be long enough to guarantee the voltage settling at the input of the A/D converter to within 0.5oC. This includes

the input interface circuits of the ADC and the externally added capacitors (CC).

It is preferable to use the minimal delay possible for the system. This depends on the capacitance on the wires and serial

resistance. TMPDLY field of ADLYCTL register defines the delay. Typically, a delay of 128 or 256 clocks (values 3 and 4,

respectively) is adequate. To find the best value, start from a high delay and reduce it until the point that the temperature

readouts starts to change. This parameter is mostly board layout and component dependent.

PC Board Layout

●Place the PC87591x as close as practical to the remote diode. In a noisy environment, such as a computer moth-

erboard, this distance can be 4 in. to 8 in. (typical) or more, as long as the worst noise sources (such as CRTs, clock

generators, memory buses and ISA/PCI buses) are avoided.

●Do not route the DP and DN lines next to high inductance signals. Also, do not route the traces across a fast memory

bus, which can easily introduce +30˚C error, even with good ﬁltering. Otherwise, most noise sources are fairly benign.

●Route the DP and DN traces in parallel and in close proximity to each other, away from any high voltage traces such

as +12V DC. Beware of leakage currents from PC board contamination; e.g., a 20 MΩleakage path from DP to

ground causes about +1˚C error.

●Connect guard traces to AGND on either side of the DP and DN traces (Figure 65). An additional AGND plane should

be placed “beneath” these traces. With guard traces and AGND plane in place, routing near high-voltage traces is no

longer a problem.

●Route through as few vias and crossunders as possible to minimize copper/solder thermocouple effects.

●When introducing a thermocouple, make sure that both the DP and DN paths have matching thermocouples.

In general, PC board-induced thermocouples are not a serious problem. A copper-solder thermocouple exhibits

3µV/˚C, and it takes about 200 µV of voltage error at DP and DN to cause a 1˚C measurement error. Therefore, most

parasitic thermocouple errors can be ignored.

●Use wide traces. Narrow ones are more inductive and tend to pick up radiated noise. The 10 mil widths and spacings

recommended in Figure 65 are not absolutely necessary (as they offer only a minor improvement in leakage and

noise), but try to use them where practical.

2N3904

Twisted Wire Pair or

Q1 PC87591x

CD= 2.2 to 3.3 nF

shielded PCB lines

Figure 64. Typical Remote Diode Circuit

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Twisted Pair and Shielded Cables

Forremotesensordistanceslongerthan8inchesorinparticularly noisy environments, a twisted pair cable is recommended.

Its practical length is 6 feet to 12 feet (typical) before noise becomes a problem, as tested in a noisy electronics laboratory.

For longer distances, the best solution is a shielded twisted pair such as that used for audio microphones. Connect the twist-

ed pair to DP and DN and the shield to AGND close to the PC87591x, and leave the remote end of the shield unterminated.

For very long cable runs, the cable parasitic capacitance adds a delay to the Temperature Channel. You should add the

cable capacitance to the value of the CD(see “Calculating the Temperature Channel Delay” on page 188) and correct the

delay setting accordingly.

Cable resistance also affects remote sensor accuracy. A 1Ω series resistance introduces about +1.0˚C to +0.5˚C error.

AGND

10 mil

Minimum

10 mil

AGND

Figure 65. DP and DN, PCB Traces

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4.12 DIGITAL TO ANALOG CONVERTER (DAC)

The DAC converts digital input values to analog signals. The DAC support four channels for handling up to four independent

conversions in parallel.

4.12.1 Features

●8-bit resolution

●Independent 4-channel D/A converter

●Fast settling time, 1 µs typical, on 50 pF capacitive load

●Output range from AGND to AVCC

●Independent enable/disable for each channel

●All converters can be automatically disabled in Idle mode

●Low power consumption when enabled; zero power consumption when disabled

●Outputs drive 0V when disabled

4.12.2 Functional Description

The DAC has four independent digital-to-analog converters. Each converter generates an output in the range of 0V to AVCC,

with 8-bit resolution. The converters drive the four output pins DA0-3, as shown in Figure 67. An output impedance of 3 KΩ

allows a settling time of about 1 µs on a 50 pF load.

When a DAC channel is enabled, its output is defined by the value written to its DACDATn register. DACDAT0-3 control

DA0-3, respectively. The maximum output voltage is (255 ÷256) *AVCC and is obtained for a value of FF16. The minimum

output, 0V, is obtained for a value of 0016.

The reference voltage of the converters is the AVCC analog power supply voltage. This allows full swing of the outputs from

0V to nearly AVCC.

After reset, all four channels are disabled and the voltage on the DA0-3 outputs is 0V.

In Idle mode, the DAC channels may be enabled or disabled (to reduce power consumption). Two control modes are pro-

vided:

●Automatic disable of all channels on entering Idle mode

●Selective disable of channels by software, before entering Idle mode

4.12.3 D/A Conversion

Output Signal

The DAC performs a linear conversion of the input digital value DACDATA7-0 registers to a unipolar analog output signal,

relative to the analog ground pin (AGND).

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When the value of DACDATA7-0 is 0016, the respective output has an output signal of 0V (AGND). When the value of

DACDATn register is FF16, the respective output has an output signal of (255/256) *AVCC. For other values, as shown in

Figure 66:

VOUT = (DACDATAn) *(AVCC / 256)

Reference Voltage

The analog output voltages are converted relative to a reference voltage. The reference voltage of the converters is the an-

alog power supply. To assure good signal quality at the output, a low-noise analog power supply should be used.

Conversion Time

When a DAC channel is enabled, the conversion is started by writing to DACDATn registers. The output settling time is de-

fined as the time the DAC requires to get to within 1/2 LSB of the final value; see “Output Settling Time” on page 195.

0123(256)

255254

. . . .

1/256

2/256

3/256

254/256

255/256

. . . . .

Level Data

[LSBits]

Voltage Ratio to AVCC

Figure 66. Channel Data to Output Voltage Ratio Conversion

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4.12.4 Operation

Initializing the DAC

The PC87591x wakes up after power-up with all the D/A channels disabled (DACEN0-3 bits in DACCTRL register are

cleared to 0). In this state, all DAC activities are halted, and its current consumption is reduced to zero.

DACDATn registers (n=0 to 3) must be initialized to 0016, or according to the required output level, before setting DACEN0-3

in DACCTRL register to 1.

Enabling and Disabling the DAC

Enabling the DAC. Each channel of the DAC is enabled independently by setting its DACEN bit. After enabling, it settles to

the value stored in DACDATn register after the specified settling time.

Disabling the DAC. The DAC channels may be independently disabled in order to reduce current consumption by clearing

the corresponding DACENn (n=0 to 3) bit in DACCTRL register. In this case, the output pin drives 0V, even if the respective

DACDATn register does not contain 0016.

Figure 67. DAC Functional Diagram

DAC0 DA0

DA1

DA2

DA3

AVCC

AGND

DAC

DACDAT0

Analog

Power

AVCC

to other

modules

DAC

Control

DAC1

DACDAT1

DAC2

DACDAT2

DAC3

VREF

DACDAT3

IDLE

AVCC

VREF

3.3V

Peripheral Bus

PC87591x

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All DAC channels are automatically disabled when entering Idle mode if ENIDLE bit in DACCTRL register is cleared to 0.

This happens regardless of the state of DACENn (n=0 to 3) bit in DACCTRL register. In this case, the DA0-3 outputs drive

0V.

If the ENIDLE bit is set to 1, entering the Idle mode does not affect DAC operation, and DA0-3 outputs drive the voltage level

set by DACDATn (n=0 to 3) registers.

4.12.5 DAC Registers

The DAC interfaces with the core using one control and four data registers. These registers are mapped to the core address

space, as defined in Appendix A on page 408.

DAC Register Map

DAC Control Register (DACCTRL)

This register controls the operation of the DAC module. DACCTRL is cleared (0016) on reset.

Location: 00 FF4016

Type: R/W

Mnemonic Register Name Type

DACCTRL DAC Control R/W

DACDAT0 DAC Data Channel 0 R/W

DACDAT1 DAC Data Channel 1 R/W

DACDAT2 DAC Data Channel 2 R/W

DACDAT3 DAC Data Channel 3 R/W

Bit 76543210

Name Reserved ENIDLE DACEN3 DACEN2 DACEN1 DACEN0

Reset 00000000

Bit Description

0DACEN0 (DAC Channel 0 Enable). Enables the DAC channel. The DA0 output pin drives a voltage level,

according to the value written into the corresponding DACDAT0 register.

When cleared, the DA0 output pin drives 0V.

0: Disabled (default)

1: Enabled

1DACEN1 (DAC Channel 1 Enable). Same as DACEN0 bit description, using DA1 output and DACDAT1

2DACEN2 (DAC Channel 2 Enable). Same as DACEN0 bit description, using DA2 output and DACDAT2

3DACEN3 (DAC Channel 3 Enable). Same as DACEN0 bit description, using DA3 output and DACDAT3

4ENIDLE (Enable in Idle). Controls the DAn (n=0 to 3) outputs in Idle mode.

0: Disabled - DAn outputs drive 0V (default)

1: Enabled - DAn outputs according to DACENn bits and DACDATn registers

7-5 Reserved.

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DAC Data Channel 0-3 Registers (DACDAT0-3)

These registers hold the data to be loaded into Channels 0-3 of the DAC. These registers are not affected by reset or disable

of the respective channel.

Location: Channel 0 - 00 FF4216

Channel 1 - 00 FF4416

Channel 2 - 00 FF4616

Channel 3 - 00 FF4816

Type: R/W

4.12.6 Usage Hints

Power Consumption

When a channel is enabled and no load is connected, the DAC current consumption depends on the value set in DACDAT

DAC Output Protection

To maintain the high performance of the analog circuits, the DAn (n=0 to 3) pins are not back-drive protected. Therefore, the

voltage applied to these pins must be within the AGND to AVCC range; otherwise the device may be damaged.

External circuits should not drive currents into these pins when the PC87591x is not powered up, because this may cause

the internal power-up reset circuit to fail.

Output Voltage Accuracy

Besides the intrinsic accuracy of the D/A channels, the output voltage accuracy directly depends on the accuracy of the

AVCC power supply, which serves as reference voltage. In order to improve the accuracy of the output voltage, the actual

AVCC value, measured by the ADC module (see Section 4.11 on page 170), should be used when computing the value of

DACDATA7-0 in DACDATn registers (see Section 4.12.3 on page 190).

The external load on DA0-3 pins may also affect the final output voltage of the DAC. Since the output resistance of these

pins is typically 3 KΩ, use high-impedance loads; if high accuracy or high output currents are required, use external analog

drivers.

For the worst case calculation, if the output resistance is 4 KΩ(maximum limit), the external load (RL) must not be lower

than 2 MΩ (see Figure 68). In this case, the error caused by the load is lower than 1/2 LSB.

To work with loads of 3 KΩ(1 mA at 3V) with an error lower than 1/2 LSB, the output resistance of the external driver should

be lower than:

ROEXT <3 KΩ/(2

*256) = 5.8 Ω

Bit 76543210

Name DAC DATAi

Bit Description

7-0 DAC Data. 8-bit unsigned binary value used for the D/A operation.

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Output Settling Time

The DAC output settling time depends on the external load characteristics and the required accuracy. Figure 68 shows the

equivalent circuit used for evaluating DAC behavior. Each DAC output has a typical output impedance of 3 KΩ. For example,

if the total load is a 50 pF capacitor only, the output settles to 1/2 LSB within 1 µs. The total load capacitance is comprises

the analog output capacitance (CAO) and the external load capacitance (CL).

Filtering Noise on Output Signals

Output signals may have unwanted noise caused by nearby digital circuits. When using slow changing signals in a noisy

environment, a low-pass filter (LPF) may be added externally. This may also be required in applications where the DAC out-

puts control sensitive circuits like audio amplifiers. This can be implemented as a simple RC circuit. The cutoff frequency of

this LPF should be above the required signal frequency.

Figure 68. DAC Output Equivalent Circuit

CAO RL

ApplicationDAC Output

Equivalent Circuit Load Circuit

VOUT

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4.13 ACCESS.BUS (ACB) INTERFACE

The PC87591x includes two ACCESS.bus interface modules. The registers of each module are prefixed with ACBn, where

‘n’ is module number 0 or 1. The signal names are suffixed with ‘n’.

Each ACCESS.bus (ACB) interface is a two-wire serial interface that is compatible with the ACCESS.bus physical layer. It

is also compatible with Intel’s SMBus and Philips’ I2C bus. The module can be configured as either a bus master or slave

and can maintain bidirectional communication with multiple master and slave devices. As a slave device, the ACB module

may issue a request to become the bus master.

The ACB interface provides full support for a two-wire ACCESS.bus synchronous serial interface. It permits easy interfacing

to a wide range of low-cost memories and I/O devices, including EEPROMs, SRAMs, timers, A/D converters, D/A convert-

ers, clock chips and peripheral drivers.

4.13.1 Features

●ACCESS.bus, SMBus and I2C compliant

●ACCESS.bus master

●ACCESS.bus slave

—One or two user-deﬁned addresses

—Global (broadcast) address

—ARP address

●Supports polling- or interrupt-controlled operation

●Generates a wake-up signal on detection of a Start Condition in Power-Down mode

●Optional internal pull-up on SDAn and SCLn pins

4.13.2 Functional Description

The ACCESS.bus protocol uses a two-wire interface for bidirectional communication between the ICs connected to the bus.

The two interface lines are the Serial Data Line (SDL) and the Serial Clock Line (SCLn). These lines should be connected

to a positive supply via a pull-up resistor and remain high even when the bus is idle.

The ACCESS.bus protocol supports multiple master and slave transmitters and receivers. Each IC has a unique address

and can operate as a transmitter or a receiver. Some peripherals are receivers only.

During data transactions, the master device initiates the transaction, generates the clock signal and terminates the transac-

tion. For example, when the ACB initiates a data transaction with an attached ACCESS.bus-compliant peripheral, the ACB

becomes the master. When the peripheral responds and transmits data to the ACB, their master/slave (data transaction ini-

tiator and clock generator) relationship is unchanged even though their transmitter/receiver functions are reversed.

Data Transactions

One data bit is transferred during each clock pulse. Data is sampled during the high state of the serial clock (SCLn). Con-

sequently, throughout the clock’s high period, the data should remain stable (see Figure 69). Any change on the SDAn line

while SCLn is in high state during a transaction causes the current transaction to abort. New data should be sent during the

low SCLn state. This protocol permits a single data line to transfer both command/control information and data, using the

synchronous serial clock.

Each data transaction is composed of a Start Condition, a number of byte transfers (set by the software) and a Stop Condi-

tion to terminate the transaction. Each byte is transferred with the most significant bit first. An Acknowledge signal must fol-

low each byte (8 bits). The following sections provide further details of this process.

SDAn

SCLn

Data Line

Stable:

Data Valid

Change

of Data

Allowed

Figure 69. Bit Transfer

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At each clock cycle, the slave can stall the master while it handles the previous data or prepares new data. The slave does

this, for each bit transferred or on a byte boundary, by holding SCLn low to extend the clock low period. Typically, slaves

extend the first clock cycle of a transfer if a byte read has not yet been stored or if the next byte to be transmitted is not yet

ready. Some microcontrollers with limited hardware support for the ACCESS.bus extend the access after each bit, thus al-

lowing the software time to handle this bit.

The ACCESS.bus master generates Start and Stop Conditions (control codes). After a Start Condition is generated, the bus

is considered busy. It retains this status for a given amount of time after a Stop Condition is generated. A high-to-low tran-

sition of the data line (SDAn) while the clock (SCLn) is high indicates a Start Condition. A low-to-high transition of the SDAn

line while the SCLn is high indicates a Stop Condition (Figure 70).

Inaddition to the first Start Condition, a Repeated Start Condition can be generated in themiddle of a transaction. This allows

either another device to be accessed or a change in the direction of the data transfer.

Acknowledge Cycle

The Acknowledge cycle consists of two signals:

●Acknowledge Clock pulse is sent by the master with each byte transferred

●Acknowledge signal is sent by the receiving device (Figure 71)

The master generates the Acknowledge clock pulse on the ninth clock pulse of the byte transfer. The transmitter releases

the SDAn line (permitting it to go high) to allow the receiver to send the Acknowledge signal.The receiver pulls down the

SDAn line during the Acknowledge clock pulse, thus signalling that it has correctly received the last data byte and is ready

to receive the next byte. Figure 72 illustrates the Acknowledge cycle.

SDAn

SCLn SP

Start

Condition Stop

Condition

Figure 70. Start and Stop Conditions

Start

Condition Stop

Condition

SDAn

SCLn

MSB

ACK ACK

3 - 6 78912 3 - 8 9

Acknowledge Signal

from Receiver

Byte Complete

Interrupt within

Receiver

Clock Line Held

Low by Receiver

while Interrupt

is Serviced

Figure 71. ACCESS.bus Data Transaction

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“Acknowledge After Every Byte” Rule

The master generates an Acknowledge clock pulse after each byte transfer. The receiver sends an Acknowledge signal after

every byte is received.

There are two exceptions to the “acknowledge after every byte” rule:

●When the master is the receiver, it must indicate to the transmitter an end of data by not acknowledging (negative

acknowledge) the last byte clocked out of the slave. This negative acknowledge still includes the Acknowledge clock

pulse (generated by the master), but the SDAn line is not pulled down.

●When the receiver is full or otherwise occupied, or if a problem occurs, it sends a negative acknowledge to indicate

that it cannot accept additional data bytes.

Addressing Transfer Formats

Each device on the bus has a unique address. Before any data is transmitted, the master transmits the address of the slave

being addressed. The slave device should send an Acknowledge signal on the SDAn line once it recognizes its address.

The address consists of the first seven bits after a Start Condition. The eighth bit contains the direction of the data transfer

(R/W). A low-to-high transition during a SCLn high period indicates the Stop Condition and ends the transaction of SDAn

(Figure 73).

When the address is sent, each device in the system compares this address with its own. If there is a match, the device

considers itself addressed and sends an Acknowledge signal. Depending on the state of the R/W bit (1=read, 0=write), the

device acts as a transmitter or a receiver.

The I2C bus protocol allows a general call address to be sent to all slaves connected to the bus. The first byte sent specifies

the general call address (0016); the second byte specifies the general call meaning (for example, “Write slave address by

software only”). Slaves that require data acknowledge the call and become slave receivers; other slaves ignore the call.

Start

Condition

SCLn 12

3 - 6 789

Transmitter Stays Off the

Bus During the

Acknowledge Clock

Acknowledge

Signal from Receiver

Figure 72. ACCESS.bus Acknowledge Cycle

Data Output

Transmitter

Data Output

Receiver

Start

Condition Stop

Condition

SDAn

SCLn 1 - 7 891 - 7 891 - 7 89

Address R/WACK Data ACK Data ACK

Figure 73. A Complete ACCESS.bus Data Transaction

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Arbitration on the Bus

Multiple master devices on the bus require arbitration between their conflicting bus access demands. Control of the bus is

initially determined according to address bits and clock cycle. If more than one master tries to address the same slave, data

comparisons determine the outcome of this arbitration. In Master mode, the device immediately aborts a transaction if the

value sampled on the SDAn line differs from the value driven by the device. (An exception to this rule is SDAn while receiving

data; in this case, the lines may be driven low by the slave without causing an abort.)

The SCLn signal is monitored for clock synchronization to allow the slave to stall the bus. The actual clock period is the long-

est one set by the master or the slave stall period. The clock high period is determined by the master with the shortest clock

high period.

When an abort occurs during address transmission, a master that identifies the conflict should give up the bus and switch

to Slave mode. It should then continue to sample SDAn to see if it is being addressed by the winning master on the bus.

4.13.3 Master Mode

Requesting Bus Mastership

An ACCESS.bus transaction starts with a master device requesting bus mastership. It asserts a Start Condition, followed by

the address of the device it wants to access. If this transaction is successfully completed, the software may assume that the

device has become the bus master.

For the device to become the bus master, the software should perform the following steps:

1. Configure INTEN in ACBnCTL1 register to the desired operation mode (Polling or Interrupt) and set START in the same

conditions, such as when BB in ACBnCST register is set to 0, can delay start). It then stalls the bus by holding SCLn low.

2. If a bus conflict is detected (i.e., some other device pulls down the SCLn signal before the PC87591x does), BER in

ACBnST register is set.

3. If there is no bus conflict, MASTER and SDAST in ACBnST register are set.

4. If INTEN in ACBnCTL1 register is set and either BER or SDAST in ACBnST register is set, an interrupt is sent to the core.

Sending the Address Byte

Once the PC87591x is the active master of the ACCESS.bus (MASTER in ACBnST register is set), it can send the address

on the bus. The address sent should not be any of the following:

●The PC87591x’s own address, as deﬁned by ADDR in ACBnADDR register, if SAEN in ACBnADDR is set.

●The PC87591x’s own address, as deﬁned by ADDR in ACBnADDR2, if SAEN in ACBnADDR2 is set.

●The global call address, if GCMTCH in ACBnST register is set.

●The ARP address, if ARPMATCH in ACBnST register is set.

To send the address byte, use the following sequence:

1. For a receive transaction where the software requires only one byte of data, the software should set ACK in ACBnCTL1

register. If only an address needs to be sent (e.g., for quick read/write protocols) or if the device requires stall for some

other reason, set STASTRE in ACBnCTL1 register to 1.

2. Write the address byte (7-bit target device address) and the direction bit to ACBnSDA register. This causes the module

to generate a transaction. At the end of this transaction, the acknowledge bit received is copied to NEGACK in ACBnST

conflict is detected, the transaction is aborted, BER in ACBnST register is set and MASTER in ACBnST register is

cleared.

3. If STASTRE in ACBnCTL1 register is set and the transaction was successfully completed (i.e., both BER and NEGACK

in ACBnST register are cleared), STASTR in ACBnST register is set. In this case, the ACB stalls any further AC-

CESS.bus operations (i.e., holds SCLn low). If INTEN in ACBnCTL1 register is set, it also sends an interrupt to the core.

4. Iftherequesteddirectionistransmitandthestarttransactionwascompletedsuccessfully(i.e.,neitherNEGACKnorBER

in ACBnST register is set and no other master has accessed the device), SDAST in ACBnST register is set to indicate

that the module awaits attention.

5. If the requested direction is receive, the start transaction was completed successfully and STASTRE in ACBnCTL1 reg-

ister is cleared, the module starts receiving the first byte automatically.

6. Check that both BER and NEGACK in ACBnST register are cleared. If INTEN in ACBnCTL1 register is set, an interrupt

is generated when either BER or NEGACK is set.

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Master Transmit

After becoming the bus master, the device can start transmitting data on the ACCESS.bus.

To transmit a byte, the software should:

1. Check that BER and NEGACK bits in ACBnST register are cleared and SDAST bit is set. In addition, if STASTRE bit in

ACBnCTL1 register is set, make sure that STASTR bit in ACBnST register is cleared.

2. Write the data byte to be transmitted to ACBnSDA register.

When the slave responds with a negative acknowledge, NEGACK in ACBnST register is set and SDAST in ACBnST register

remains cleared. In this case, if INTEN bit in ACBnCTL1 register is set, an interrupt is sent to the core.

Master Receive

After becoming the bus master, the device can start receiving data on the ACCESS.bus.

To receive a byte, the software should:

1. Check that SDAST bit in ACBnST register is set and BER bit is cleared. In addition, if STASTRE bit in ACBnCTL1 register

is set, make sure that STASTR in ACBnST register is cleared.

2. If the next byte is the last byte that should be read, set ACK bit in ACBnCTL1 register to 1. This causes a negative ac-

knowledge to be sent.

3. Read the data byte from ACBnSDA register.

Master Stop

To end a transaction, set STOP in ACBnCTL1 register before clearing the current stall flag (i.e., SDAST, NEGACK or STAS-

TR in ACBnST register). This causes the module to send a Stop Condition immediately and to clear STOP in ACBnCTL1

is set to 1).

Master Bus Stall

The ACB module can stall the ACCESS.bus between transfers while waiting for the core’s response. The ACCESS.bus is

stalled by holding the SCLn signal low after the acknowledge cycle. Note that this is interpreted as the start of the following

bus operation. The user must make sure that the next operation is prepared before the flag that causes the bus stall is

cleared.

The flags that can cause a bus stall in Master mode are:

●Negative acknowledge after sending a byte (NEGACK in ACBnST register is set to 1).

●SDAST in ACBnST register is set to 1.

●STASTRE in ACBnCTL1 register is set to 1 after a successful start (STASTR in ACBnST is set to 1).

Repeated Start

A repeated start is performed when the PC87591x is already the bus master (MASTER in ACBnST register is set). In this

case, the ACCESS.bus is stalled and the ACB module awaits core handling due to a negative acknowledge (NEGACK in

ACBnST register is set to 1), an empty buffer (SDAST in ACBnST is set to 1) and/or a stall after start (STASTR in ACBnST

is set to 1).

For a repeated start:

1. Set START in ACBnCTL1 register to 1.

2. In Master Receive mode, read the last data item from ACBnSDA.

3. Follow the address send sequence, as described in “Sending the Address Byte” on page 199.

4. If the ACB is awaiting handling because STASTR in ACBnST is set to 1, clear it only after writing the requested address

and direction to ACBnSDA.

Master Error Detection

The ACB detects an illegal Start or Stop Condition (i.e., a Start or Stop Condition within the data transfer or the acknowledge

cycle) and a conflict on the data lines of the ACCESS.bus. If an illegal condition is detected, BER is set and Master mode is

exited (MASTER in ACBnST register is cleared).

Bus Idle Error Recovery

When a request to become the active bus master or a restart operation fails, BER in ACBnST register is set to indicate the

error. In some cases, both the PC87591x and the other device may identify the failure and leave the bus idle. In this case,

the start sequence may not finish and the ACCESS.bus may remain deadlocked.

To recover from deadlock, use the following sequence:

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1. Clear BER in ACBnST register and BB in ACBnCST register.

2. Wait for a time-out period to check that there is no other active master on the bus (i.e., BB in ACBnCST remains cleared).

3. Disable and then re-enable the ACB to put it in non-addressed Slave mode. (This completely resets the module.)

At this point, some of the slaves may not identify the bus error. To recover, the ACB module becomes the bus master. It

asserts a Start Condition, sends an address byte and then asserts a Stop Condition that synchronizes all the slaves.

4.13.4 Slave Mode

A slave device waits in Idle mode for a master to initiate a bus transaction. Whenever the ACB module is enabled is not

acting as a master (i.e., MASTER in ACBnST register is cleared), it acts as a slave device.

Once a Start Condition on the bus is detected, the PC87591x checks whether the address sent by the current master match-

es any of the following possibilities:

●The ADDR value in ACBnADDR register, if SAEN in this register is set to 1

●The ADDR value in ACBnADDR2 register, if SAEN in this register is set to 1

●The global call address (0016), if GCMEM in ACBnCTL1 register is set to 1

●The global ARP address (110 00012), if ARPMEN in ACBnCTL3 register is set to 1.

The address match is checked even when MASTER in ACBnST register is set. If a bus conflict (on SDAn or SCLn) is de-

tected, BER is set, MASTER is cleared and the PC87591x continues to search the received message for a match.

If an address ARP or global match is detected:

1. The PC87591x asserts its SDAn pin during the acknowledge cycle.

2. MATCH in ACBnCST register, MATCHAF in ACBnST register (or GCMATCH if it is a global call address match, or ARP-

MATCH if it is an ARP address) and NMATCH in ACBnST register are set. If XMIT in ACBnST register is set (i.e., Slave

Transmit mode), SDAST in the same register is also set to indicate that the buffer is empty.

3. If INTEN in ACBnCTL1 register is set, an interrupt is generated if both INTEN and NMINTE in ACBnCTL1 register are set.

4. The software then reads XMIT in ACBnST register to identify the direction requested by the master device; it then clears

NMATCH in the same register so that future byte transfers are identified as data bytes.

Slave Receive and Transmit

Slave Receive and Transmit are performed after a match is detected and the data transfer direction is identified. After a byte

transfer, the ACB module extends the acknowledge clock until the software reads or writes ACBnSDA register. The receive

and transmit sequences are identical to those used in the master routine.

Slave Bus Stall

When operating as a slave, the PC87591x stalls the ACCESS.bus by extending the first clock cycle of a transaction in the

following cases:

●SDAST in ACBnST register is set.

●NMATCH in ACBnST register and NMINTE in ACBnCTL1 register are set.

Slave Error Detection

The ACB detects illegal Start and Stop Conditions (occurring within the data transfer or the acknowledge cycle) on the AC-

CESS.bus. When an illegal Start or Stop Condition is detected, BER is set and MATCH and GMATCH are cleared, setting

the module as an unaddressed slave.

4.13.5 Power-Down

When the PC87591x is in Idle mode, the ACB module is not active but retains its status. If the ACB is enabled (ENABLE in

ACBnCTL2 register is set) on detection of a Start Condition, a wake-up signal is issued to the MIWU. This signal may be

used to switch the PC87591x to Active mode.

Following the Start Condition that woke up the PC87591x, the ACB module can not check the address byte for a match. The

ACB responds with a negative acknowledge. The device should resend both the Start Condition and the address after the

PC87591x has had time to wake up.

Before entering Idle mode, make sure that BUSY in ACBnCST register is inactive. This guarantees that the PC87591x will

not stop responding after it acknowledges an address that was sent.

4.13.6 SDA and SCL Pin Configuration

The SDAn and SCLn are open collector signals that the user can choose to enable or disable. SDAn and SCLn also have

internal pull-up resistors that the user may enable. For more information about configuring these pins, see Table 8 on

page 54 and Section 4.5.2 on page 114.

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4.13.7 ACB Clock Frequency Configuration

The ACB module enables the user to set the ACCESS.bus clock frequency. The SCLn clock period is set by SCLFRQ in

ACBnCTL2 and ACBnCTL3 registers. This clock low period may be extended by stall periods initiated by the ACB module

or by another ACCESS.bus device. In case of a conflict with another bus master, a shorter clock high period may be forced

by the other bus master until the conflict is resolved.

4.13.8 ACB Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

ACB Register Map

ACB Serial Data Register (ACBnSDA)

The ACBnSDA register is a shift register used to transmit and receive data. The most significant bit is transmitted (received)

first and the least significant bit is transmitted (received) last. Reading or writing to the ACBnSDA register is allowed only

when SDAST in ACBnST register is set or for repeated starts after setting the START bit. An attempt to access the register

in other cases may produce unpredictable results.

Locations: Channel - 1 00 FF6016

Channel - 2 00 FFE016

Type: R/W

Mnemonic Register Name Type

ACBnSDA ACB Serial Data R/W

ACBnST ACB Status Varies per bit

ACBnCST ACB Control Status Varies per bit

ACBnCTL1 ACB Control 1 R/W

ACBnADDR ACB Own Address R/W

ACBnADDR2 ACB Own Address 2 R/W

ACBnCTL2 ACB Control 2 R/W

ACBnCTL3 ACB Control 3 R/W

Bit 76543210

Name Data

Bit Description

7-0 Data.

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ACB Status Register (ACBnST)

The ACBnST register maintains current ACB status. Some of its bits may be cleared by software, as described below. On

reset, and when the module is disabled, ACBnST is cleared (0016).

Location: Channel - 1 00 FF6216

Channel - 2 00 FFE216

Type: varies per bit

Bit 76543210

Name SLVSTP SDAST BER NEGACK STASTR NMATCH MASTER XMIT

Reset 00000000

Bit Type Description

0ROXMIT (Transmit Mode).

0: ACB not in master/slave Transmit mode

1: ACB in master/slave Transmit mode

1ROMASTER (Master Mode).

0: Arbitration loss (BER is set) or Stop Condition occurred

1: ACB in Master mode (successful request for bus mastership)

2 R/W1C NMATCH (New Match). The bit is set when the address byte following a Start Condition or a

repeated start causes an address match, ARP address match or a global call match. NMATCH is

cleared by writing 1 to it. Writing 0 to NMATCH is ignored. If INTEN in ACBnCTL1 register is set, an

interrupt is sent when this bit is set.

3 R/W1C STASTR (Stall After Start). The bit is set by the successful completion of sending an address (i.e.,

a Start Condition sent without a bus error or negative acknowledge), if STASTRE in ACBnCTL1

pulling down the SCL line) and suspends any further action on the bus (e.g., receiving the ﬁrst byte

in Master Receive mode). In addition, if INTEN in ACBnCTL1 register is set, it also causes the ACB

module to send an interrupt to the core. Writing 1 to STASTR clears it. It is also cleared when the

module is disabled and is always cleared when STASTRE is cleared. Writing 0 to STASTR has no

effect.

4 R/W1C NEGACK (Negative Acknowledge). The bit is set by hardware when a transmission is not

acknowledged on the ninth clock (in this case, SDAST is not set). Writing 1 to NEGACK clears it. It is

also cleared when the module is disabled. Writing 0 to NEGACK is ignored.

5 R/W1C BER (Bus Error). The bit is set by the hardware when a Start or Stop Condition is detected during

data transfer (i.e., Start or Stop Condition during the transfer of bits 2 through 8 and acknowledge

cycle) or when an arbitration problem is detected. Writing 1 to BER clears it. It is also cleared when

the module is disabled. Writing 0 to BER is ignored.

6ROSDAST (SDA Status). When set, this bit indicates that the SDA data register is waiting for data

(Transmit mode - master or slave) or holds data that should be read (Receive mode - master or

slave). This bit is cleared when reading from ACBnSDA register during a receive or when written to

during a transmit. When START in the ACBnCTL1 is set, reading ACBnSDA register does not clear

SDAST. This enables the ACB to send a repeated start in Master Receive mode.

7 R/W1C SLVSTP (Slave Stop). When set, SLVSTP indicates that a Stop Condition was detected after a slave

transfer (i.e., after a slave transfer in which MATCH or GCMATCH was set). Writing 1 to SLVSTP

clears it. It is also cleared when the module is disabled. Writing 0 to SLVSTP is ignored.

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ACB Control Status Register (ACBnCST)

The ACBnCST register maintains current ACB status and controls several ACB module functions, as described below. On

reset and when the module is disabled, the non-reserved bits of ACBnCST are cleared (0016).

Location: Channel 1 - 00 FF6416

Channel 2 - 00 FFE416

Type: Varies per bit

Bit 76543210

Name ARPMATCH MATCHAF TGSCL TSDA GCMATCH MATCH BB BUSY

Reset 00000000

Bit Type Description

0ROBUSY. When set (1), indicates that the ACB module is in one of the following states:

– Generating a Start Condition

– In Master mode (MASTER in ACBnST register is set)

– In Slave mode (MATCH or GMATCH in ACBnCST register is set)

– In the period between detecting a Start Condition and completing the reception of the address byte;

after this, the ACB either becomes not busy or enters Slave mode.

The BUSY bit is cleared by the completion of any of the above states or by disabling the module. It

should always be written 0.

1 R/W1C BB (Bus Busy). When set (1), indicates the bus is busy. It is set either when the bus is active (i.e., a

low level on either SDA or SCL) or by a Start Condition. It is cleared when the module is disabled, on

detection of a Stop Condition or by writing 1 to this bit. See Section 4.13.9 on page 207 for a

description of the use of this bit.

2ROMATCH (Address Match). In Slave mode, MATCH is set (1) when SAEN in ACBnADDR register is

set and the first seven bits of the address byte (the first byte transferred after a Start Condition) match

the 7-bit address in ACBnADDR register. It is cleared by Start Condition, a Repeated Start or a Stop

Condition (including illegal Start or Stop Condition).

3ROGCMATCH (Global Call Match). In Slave mode, GCMTCH is set (1) when GCMEN in ACBnCTL1

cleared by a Start Condition, a Repeated Start or a Stop Condition (including illegal Start or Stop

Condition).

4ROTSDA (Test SDA Line). Reads the current value of the SDA line. This bit can be used while

recovering from an error condition in which the SDA line is constantly pulled low by a slave that went

out of synch. Data written to this bit is ignored.

5 R/W TGSCL (Toggle SCL Line). Enables toggling the SCL line during the process of error recovery. When

the SDA line is low, writing 1 to this bit toggles the SCL line for one cycle. Writing 1 to TGSCL while

SDA is high is ignored. The bit is cleared when the clock toggle is completed.

6ROMATCHAF (Match Address Field). When the MATCH bit is set, MATCHAF indicates with which of

the two possible slave addresses (ADDR cleared in ACBnADDR register or set in ACBnADDR2

7ROARPMATCH (ARP address Match). In Slave mode, ARPMTCH is set (1) when ARPMEN in

ACBnCTL3 register is set and the address byte (the ﬁrst byte transferred after a Start Condition) is

110 00012. It is cleared by Start Condition, a Repeated Start or a Stop Condition (including illegal Start

or Stop Condition).

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ACB Control Register 1 (ACBnCTL1)

The ACBnCTL1 register is a byte-wide, read/write register that configures and controls the ACB module. On reset, the

ACBnCTL1 is cleared (0016).

Location: Channel 1 - 00 FF6616

Channel 2 - 00 FFE616

Type: R/W

Bit 76543210

Name STASTRE NMINTE GCMEN ACK Reserved INTEN STOP START

Reset 00000000

Bit Description

0START. Should be set when a Start Condition must be generated on the ACCESS.bus.

– If the PC87591x is not the active bus master (MASTER in ACBnST register is set to 0), setting START gener-

ates a Start Condition as soon as the ACCESS.bus is free (BB in ACBnCST register is set to 0). An address

transmission sequence should then be performed.

– If the PC87591x is the active master of the bus (MASTER in ACBnST register is set to 1), when START is set,

a write to ACBnSDA register generates a Start Condition. ACBnSDA data is then transmitted as the slave’s ad-

dress and the requested transfer direction.

In case of a Repeated Start Condition, the set bit may be used to switch the direction of the data flow between

the master and the slave or to choose another slave device without using a Stop Condition in between.

The START bit is cleared either when the Start Condition is sent or on detection of a Bus Error (BER in ACBnST

This bit should be set only when in Master mode or when requesting Master mode.

1STOP. In Master mode, setting this bit generates a Stop Condition, which completes or aborts the current

message transfer. This bit clears itself after STOP is issued.

2INTEN (Interrupt Enable). When INTEN is cleared (0), the ACB interrupt is disabled. When INTEN is set,

interrupts are enabled. An interrupt is generated (the interrupt signals to the ICU are high) on one of the

following events:

– An address match is detected (NMATCH in ACBnST register is set to1 and NMINTE in ACBnCTL1 register is

set to 1).

– A Bus Error occurs (BER in ACBnST register is set to 1).

– A negative acknowledge is received after sending a byte (NEGACK in ACBnST register is set to 1).

– Acknowledgment of each transaction (same as the hardware set of SDAST in ACBnST).

– In Master mode, if STASTRE in ACBnCTL1 register is set to 1 after a successful start (STASTR in ACBnST

– Detection of a Stop Condition while in Slave mode (SLVSTP in ACBnST register is set to 1).

3Reserved.

4ACK (Acknowledge). When acting as a receiver, this bit holds the value of the next acknowledge cycle. It

should be set when a negative acknowledge must be issued on the next byte. This bit is cleared (0) after the

ﬁrst acknowledge cycle.

This bit is ignored when in Transmit mode. It cannot be reset by software.

5GCMEN (Global Call Match Enable). When set, enables the matching of an incoming address byte to the

general call address (Start Condition followed by address byte of 0016) while the ACB is in Slave mode. When

cleared, the ACB does not respond to a global call.

6NMINTE (New Match Interrupt Enable). When set, enables the interrupt on a new match (i.e., when NMATCH

in ACBnST register is set). The interrupt is issued only if INTEN in ACBnCTL1 register is set.

7STASTRE (Stall After Start Enable). When set (1), enables the Stall After Start mechanism. In such a case,

the ACB stalls the bus after the address byte. When STASTRE is cleared, STASTR in ACBnST is always

cleared.

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ACB Own Address Register (ACBnADDR and ACBnADDR2)

The ACBnADDR and ACBnADDR2 registers hold the module’s ACCESS.bus addresses. The reset value of these registers

are undefined.

ACBnADDR:

Location: Channel 1 - 00 FF6816

Channel 2 - 00 FFE816

ACBnADDR2:

Location: Channel 1- 00 FE6C16

Channel 2- 00 FFEC16

Type: R/W

ACB Control Register 2 (ACBnCTL2)

The ACBnCTL2 register enables/disables the module and determines the ACB clock rate. On reset and while the module is

disabled (ENABLE in ACBnCTL2 register is set to 0), ACBnCTL2 is cleared (0016).

Location: Channel 1 - 00 FF6A16

Channel 2 - 00 FFEA16

Type: R/W

Bit 76543210

Name SAEN ADDR

Bit Description

6-0 ADDR (Address). Holds the 7-bit ACCESS.bus address of the PC87591x. When in Slave mode, the first seven

bits received after a Start Condition are compared to this field (the first bit received is compared to bit 6, the next

bit to bit 5 and so on until the last bit, which is compared to bit 0). If the address field matches the received data

and SAEN in ACBnADDR register is set to 1, a match is declared.

7SAEN (Slave Address Enable). When set (1), indicates that the ADDR ﬁeld holds a valid address and enables

the match of ADDR to an incoming address byte. When cleared, the ACB does not check for an address match.

Bit 76543210

Name SCLFRQ6-0 ENABLE

Reset 00000000

Bit Description

0ENABLE. When set, the ACB module is enabled. When the Enable bit is cleared, the ACB module is disabled,

ACBnCTL1, ACBnST and ACBnCST are cleared and the clocks are halted.

7-1 SCLFRQ6-0 (SCL Frequency bits 6 through 0). This ﬁeld, together with SCLFRQ8-7 in ACBCTL3 register,

defines the SCL’s period (low time and high time) when the PC87591x serves as a bus master. The clock low

time and high time are defined as follows:

tSCL =4*SCLFRQ*tCLK

tSCLl =t

SCLh

where tCLK is the PC87591x clock cycle when in Active mode (see Section 7.6.3 on page 385).

SCLFRQ may be programed to values in the range of 00 00010002(810) through 11 11111112(51110). Values

outside this range gives unpredictable results.

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ACB Control Register 3 (ACBnCTL3)

The ACBnCTL3 register expands the clock pre-scaler field and enables the match to ARP addresses. ACBnCTL2 is cleared

on reset (0016).

Location: Channel 1 -00 FF6E16

Channel 2- 00 FFEE16 (Update for Multiple Instances)

Type: R/W

4.13.9 Usage Hints

1. When the ACB is disabled, BB in ACBnCST register is cleared. After the ACB is enabled (by setting ENABLE in

ACBnCTL2 register), the bus may be in the middle of a transaction with another device in systems with more than one

master. This status is not reflected by BB.

To prevent bus errors, the ACB must synchronize with the bus activity status before issuing a request to become the bus

master for the first time. The software should check that there is no activity on the bus by checking the BB bit after the

time-out period allowed by the bus.

2. When waking up from power-down before checking MATCH in ACBnCST register, check BUSY in the same register to

make sure that the address transaction is completed.

3. The BB bit can help solve a deadlock in which two or more devices detect a usage conflict on the bus and both cease

being bus masters at the same time. In this situation, the BB bits of both devices are active (because each “detects”

another master currently performing a transaction, while in fact there is no transaction). This potentially causes the bus

to stay locked until a device on the bus sends a Stop Condition (through STOP in ACBnCTL1 register).

The BB bit allows the software to monitor bus usage so that it can detect whether the bus remains unused over a certain

period of time while BB is set. It also avoids sending a STOP signal in the middle of the transaction of another device on

the bus.

4. In some cases, the bus may get stuck with the SCL and/or SDA lines active, such as when an erroneous Start or Stop

Condition occurs in the middle of a slave receive session.

If the SCL line is stuck active, the module that holds the bus must release it.

If the SDA line is stuck active, the sequence below releases the bus (Note:In normal cases, SCL may be toggled only

by the bus master; this sequence is a recovery scheme which is an exception and should be only used if there is no other

master on the bus):

a. Disable and re-enable the module to set it for the Slave mode not addressed.

b. Set START in ACBnCTL1 register to attempt to issue a Start Condition.

c. Check if the SDA line is active (low) by reading TSDA in ACBnCST register. If it is active, issue a single SCL cycle

by writing 1 to TGSCL in the same register. If it is not active, skip to step e.

d. Check if MASTER in ACBnST register is set, which indicates that the Start Condition was sent. If it is not set, repeat

step c and this step until the SDA is released.

e. Clear BB. This enables START to be executed. Continue according to “Bus Idle Error Recovery” on page 200.

Bit 76543210

Name Reserved ARPMEN SCLFRQ8-7

Reset 00000000

Bit Description

1-0 SCLFRQ8-7 (SCL Frequency bits 8 and 7). Extends SCLFRQ ﬁeld and is concatenated with bits 0-6, which

are part of ACBnCTL2 register. Detailed use of SCLFRQ is provided in the SCLFRQ6-0 description in

ACBnCTL2.

2ARPMEN (ARP Match Enable). When set, enables the matching of an incoming address byte to the SMBus

ARP address (110 00012) while the ACB is in Slave mode. When cleared, the ACB does not respond to an ARP

address.

7-3 Reserved.

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4.14 ANALOG COMPARATORS MONITOR (ACM)

The Analog Comparators Monitor (ACM) checks the voltage level of eight analog inputs and reports their values to the core.

The ACM can either measure the voltage of each input with 6-bit resolution or compare the level of all eight inputs with a

programmable threshold.

An operation burst includes either the voltage measurement of all inputs or one comparison check of all inputs to a fixed

threshold. The bursts may be triggered by a low-frequency clock for periodic operation.

4.14.1 Features

●Voltage measurement

—Eight analog inputs

—6-bit resolution

—0V to VCC Full Scale (FS) input voltage range

—High-impedance inputs

●Comparison check

—6-bit threshold resolution

—Simultaneous on all inputs

●Ratiometric measurement using VCC

●Digital reading output

—Eight buffers for voltage value

—One buffer for comparison check

●170 µs voltage measurement of all the inputs

●Polling- or interrupt-driven interface

●Power consumption

—Zero current when disabled

—Low average current in Idle mode

4.14.2 Functional Description

Inputs. The ACM has eight analog inputs with a voltage ranging from 0V to VCC (FS), as shown in Figure 74.

The voltage level at each input is compared with a reference level, generated by a 6-bit D/A converter.

Operation. The ACM can be operated in one of three modes:

●Voltage Level Burst mode - The reference level generated by the D/A converter is ramped from 0V to FS by incre-

menting the value loaded into the converter. Whenever the ramp crosses the level of an input, its comparator toggles

state, and the D/A loaded value is latched into the corresponding Voltage Level Buffer. At the end of the ramp, exe-

cution stops and a set of eight voltage level values (one per input) is available.

●Threshold Comparison Burst mode - A programmable value is loaded into the D/A converter, generating a constant

threshold level. A bit is set for each input if the input’s voltage level is higher than the threshold. At the end of the

single comparison, the Comparison Result register holds the status of the eight inputs.

●Low Power Threshold Comparison mode - The inputs are periodically compared with a ﬁxed threshold. The compar-

ison is triggered by a low rate signal from the TWD module (T0IN). In addition, an interrupt is generated if at least

one input is below (or above) the threshold.

Timing. When the PC87591x is in Active or Active Executing Wait mode, ACM module timing is based on the core domain

clock (CLK). When the PC87591x is in Idle mode, timing is based on the low frequency clock (LFCLK) to minimize power

consumption.

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4.14.3 Voltage Level

VCC supply is the reference and full scale (FS) voltage for the D/A converter. This enables ratiometric voltage measurement

(parts of FS), were VCC is used to power an external voltage divider connected to the KBSINn inputs.

The 6-bit Voltage Level Data field (VOLTLVL) in VOLDATn (n = 0 to 7) registers and the Comparison Threshold Data field

(THRSHD5-THRSHD0) in THRDAT register are converted to input voltage, according to input voltage ratio (to FS), as

shown in Figure 75.

D/A Converter

(6-bit)

Control

Logic

Voltage In0

Interrupt

System

Peripheral Bus

ACM

Clock

Voltage In1

Voltage In7

Comparison

Control/Status

LFCLK

Figure 74. ACM Functional Diagram

T0IN

Result

PC87591x

KBSIN1

KBSIN7

KBSIN0

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4.14.4 ACM Operation

Reset

The ACM is initialized by core domain reset (Section 3.2 on page 65 describes the PC87591x reset events).

Upon reset, the ACM is disabled, with all interrupt sources masked and the over/under threshold select set to “below”. All

Event status bits are reset. The trigger division factor, as well as the data sampling delay, are set to their maximum value

(for the slowest ACM operation speed). The comparison threshold is set to zero.

All control, configuration and status registers are reset to their default values, as indicated in Section 4.14.5 on page 212.

Voltage Level Data Buffer registers and the Comparison Result register’s values are invalid until the first measurement oc-

curs (on each of them).

Sampling Delay

This delay separates between the new value being loaded into the D/A converter and the data being sampled into the Volt-

age Level Data Buffer registers and the Comparison Result register. Its value should be longer than the total time required

by the D/A output to settle (within 1/2 LSB of 6 bits) and the comparators to toggle their state.

The value set by SMPDLY field in ACMTIM register is expressed in terms of core CLK clock cycles. The maximum frequency

at which each delay may be used is specified in the register’s description.

Initializing the ACM

The ACM must be initialized before it is enabled and used. The following operations should be done:

●Select the ACM Mode Control by setting ACMMOD ﬁeld in ACMCNF register.

●Enable interrupts are required using the following bits of ACMCNF register:

—Interrupt from End-of-Measurement Event Enable by setting INTEMEN bit.

—Interrupt from Over/Under Threshold Event Enable by setting INTOUEN bit.

●Select Over or Under Threshold mode, using OVUNSEL bit in ACMCNF register.

●Set the data sampling delay using SMPDLY ﬁeld in ACMTIM register.

●Select the low power trigger rate by setting T0DIV ﬁeld in ACMTIM register.

●Select the Comparison Threshold Data for wake-up by setting THRSHD ﬁeld in THRDAT register.

After initializations are done, the ACM may be enabled by writing 1 to START bit in ACMCTS register.

Note: Setting any of the above bits/fields during ACM operation may cause unpredictable results.

0123(64)

6362

. . . . .

1/64

2/64

3/64

62/64

63/64

. . . . .

Level Data

Voltage Ratio to VCC (FS)

Figure 75. Level Data to Input Voltage Ratio Conversion

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Interrupt Structure

The ACM Interrupt is generated to the core if an event from Table 26 becomes active. Since the events are enabled in dif-

ferent ACM operation modes, only one event may occur at a time.

Table 26. ACM Interrupt Structure

When an event flag and its related mask bit are set (enabled), the ACM Interrupt request is asserted. This is indicated by

a high level of the ACM Interrupt signal.

The software must reset the event flag (or its mask bit) to de-assert the ACM Interrupt request.

All the event flags (EOMEV, EOCEV and OVUNTHEV) are cleared by writing 1 to START in ACMCTS register.

TheACMInterruptisroutedbothtotheICUandtotheMIWUasanACMIsignal(seeSection 4.3onpage 98and Section 4.4

on page 105).

ACM Operating Sequences

The ACM has three operating modes:

●Voltage Level Burst mode

●Threshold Comparison Burst mode

●Low-Power Threshold Comparison mode

After the ACM is properly initialized, one of these modes should be used. The operation sequences are as follows:

Voltage Level Burst Mode (ACMMOD = 012)

1. Start a new burst of eight voltage measurements by setting START bit in ACMCTS register to 1.

2. When End-of-Voltage level measurement burst is reached, software can detect the event by waiting for EOMEV in

ACMCTS register to be set to 1.

3. Read measured voltage level - Input 0, for channel 0, by reading VOLTLVL in VOLDAT0 register.

4. Read measured voltage level - Input 1, for channel 1, by reading VOLTLVL in VOLDAT1 register.

5. Read measured voltage level - Input 2, for channel 2, by reading VOLTLVL in VOLDAT2 register.

6. Read measured voltage level - Input 3, for channel 3, by reading VOLTLVL in VOLDAT3 register.

7. Read measured voltage level - Input 4, for channel 4, by reading VOLTLVL in VOLDAT4 register.

8. Read measured voltage level - Input 5, for channel 5, by reading VOLTLVL in VOLDAT5 register.

9. Read measured voltage level - Input 6, for channel 6, by reading VOLTLVL in VOLDAT6 register.

10.Read measured voltage level - Input 7, for channel 7, by reading VOLTLVL in VOLDAT7 register.

11.Clear the event flag (release the ACM interrupt if enabled) by writing 1 to EOMEV in ACMCTS register.

Threshold Comparison Burst Mode -(ACMMOD = 102)

1. Set the desired threshold value in bits THRSHD(5-0) in THRDAT register.

2. Start a new burst of threshold comparison by setting START in ACMCTS register to 1.

3. When End-of-Threshold comparison burst is reached, software can detect the event by waiting for EOCEV in ACMCTS

4. Read comparison result for inputs 0 to 7 by reading bits CMPIN(0-7) in CMPRES register.

5. Clear the event flag by writing 1 to EOCEV in ACMCTS register.

Event Flag Register

Mnemonic Mask Bit Register

Mnemonic Description

EOMEV ACMCTS INTEMEN ACMCNF End-of-Measurement event and associated interrupt enable

OVUNTHEV ACMCTS INTOUEN ACMCNF Over/Under Threshold event and associated interrupt enable

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Low-Power Threshold Comparison Mode (ACMMOD = 112)

1. Set the desired threshold value in bits THRSHD(5-0) in THRDAT register.

2. Start a new periodic, low-power threshold comparison by setting START in ACMCTS register to 1.

3. When there is an input under (or over) threshold event, software can detect the event by waiting for OVUNTHEV in

ACMCTS register to be set to 1.

4. Read comparison result for inputs 0 to 7 by reading bits CMPIN(0-7) in CMPRES register.

5. Clear the event flag (release the ACM interrupt if enabled) by writing 1 to OVUNTHEV in ACMCTS register.

Polling Driven Operation. Valid measurement results may be retrieved by polling the event flags in ACMCTS register,

EOMEV, EOCEV or OVUNTHEV, according to the selected operation mode. After reading the relevant data, clear the polled

event flag by writing 1.

Interrupt Driven Operation. When receiving an active ACM interrupt request, the software should check the two event

flags, EOMEV or OVUNTHEV, to identify the source of the interrupt. After reading the relevant data, clear (by setting to 1)

the event flag that caused the interrupt. Clearing the flag releases the ACM interrupt request.

4.14.5 ACM Registers

The ACM control/status and data out register set interfaces with the core through the Peripheral bus.

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

ACM Register Map

The ACM register set contains four control and status registers and nine data out registers.

Table 27. ACM Register Map

Mnemonic Register Name Type

ACMCTS ACM Control and Status Varies per bit

ACMCNF ACM Conﬁguration R/W

ACMTIM ACM Timing Control R/W

THRDAT Comparison Threshold Data R/W

CMPRES Comparison Result RO

Reserved

VOLDAT0 Voltage Level Data - Input 0 RO

VOLDAT1 Voltage Level Data - Input 1 RO

VOLDAT2 Voltage Level Data - Input 2 RO

VOLDAT3 Voltage Level Data - Input 3 RO

VOLDAT4 Voltage Level Data - Input 4 RO

VOLDAT5 Voltage Level Data - Input 5 RO

VOLDAT6 Voltage Level Data - Input 6 RO

VOLDAT7 Voltage Level Data - Input 7 RO

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ACM Control and Status Register (ACMCTS)

This register controls the operation and indicates the status of the ACM module. ACMCTS is cleared (0016) on reset.

Location: 00 FD4016

Type: Varies per bit

Bit 76543210

Name Reserved OVUNTHEV EOCEV EOMEV START

Reset 00000000

Bit Type Description

0WSTART (ACM Operation Start). Start trigger for the ACM operation in the mode selected by ACMMOD

ﬁeld in ACMCNF register. If the new ACMMOD value differs from the value currently in use, all event

ﬂags (EOMEV, EOCEV, OVUNTHEV) are cleared and operation in the new mode begins. Writing a 1 to

the START bit without modifying the ACMMODE value is ignored by the module.

0: No effect - (default)

1: Operation start trigger - automatically returns to 0 after start

1 R/W1C EOMEV (End-of-Measurement Event). End of voltage level measurement burst (for all eight inputs).

The bit is set only when the ACM is in Voltage Level Burst mode (ACMMOD = 012in ACMCNF

0: Measurement in progress, or not in Voltage Level Burst mode (default)

1: End of voltage level measurement burst

2 R/W1C EOCEV (End-of-Comparison Event). End of threshold comparison in Threshold Comparison Burst

mode (ACMMOD = 102in ACMCNF register).

0: Comparison in progress, or not in Threshold Comparison Burst mode (default)

1: End of threshold comparison

3 R/W1C OVUNTHEV (Over/Under Threshold Event). At least one input is above (or below) the voltage

threshold value. The bit is set only when the ACM is in Low Power Threshold Comparison mode

(ACMMOD = 112in ACMCNF register).

0: No input above (or below) the threshold, or not in Low Power Threshold Comparison mode (default)

1: One or more inputs above (or below) the threshold

7-4 Reserved.

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ACM Conﬁguration Register (ACMCNF)

This register controls the configuration of the ACM module. ACMCNF is cleared (0016) on reset.

Location: 00 FD4216

Type: R/W

Bit 76543210

Name Reserved OVUNSEL INTOUEN INTEMEN Reserved ACMMOD

Reset 00000000

Bit Description

1-0 ACMMOD (ACM Mode Control). Conﬁgures the operation mode of the ACM module. See “ACM Operating

Sequences” on page 211. This value becomes the active mode after writing a 1 to START bit in ACMCTS

Bits

1 0 Description

0 0: ACM disabled (default)

0 1: Voltage Level Burst mode - single measurement of the voltage level for all the eight inputs

1 0: Threshold Comparison Burst mode - single comparison of all the eight inputs to the set threshold

1 1: Low-Power Threshold Comparison mode - periodic comparison of the inputs to a constant threshold

(recommended for Idle PC87591x operation mode). Its operation is stopped by the

selection of a different mode (ACM disabled = 002 is the recommended value).

2Reserved.

3INTEMEN (Interrupt from End-of-Measurement Event Enable). Enables generation of an ACM interrupt on an

End of Voltage Measurement Burst event (EOMEV in ACMCTS register).

0: Disabled (default)

1: Enabled - ACM Interrupt from EOMEV

4INTOUEN (Interrupt from Over/Under Threshold Event Enable). Enables generation of an ACM interrupt on

at least one input above (or below) the threshold event (OVUNTHEV ACMCTS register).

0: Disabled (default)

1: Enabled - ACM Interrupt from OVUNTHEV

5OVUNSEL (Over or Under Threshold Select). “Any Over” or “Any Under” logic selection for OVUNTHEV bit in

ACMCTS register.

0: At least one input below threshold sets OVUNTHEV=1 (default)

1: At least one input above threshold sets OVUNTHEV=1

7-6 Reserved.

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ACM Timing Control Register (ACMTIM)

This register controls the sampling delay for the voltage level and compare out data; it also controls the division of the trigger

signal. ACMTIM is set to 3716 on reset.

Location: 00 FD4416

Type: R/W

Bit 76543210

Name Reserved T0DIV Reserved SMPDLY

Reset 0 0 110111

Bit Description

2-0 SMPDLY (Data Sampling Delay). Compensates for the settling time of the D/A converter and the input

comparators. To calculate the required delay value, see “Sampling Delay” on page 210.

Bits Settling Compare Max

2 1 0 Period1 Period1 Core Freq2

0 0 0: 1 10 5.5MHz

0 0 1: 1 15 8.5 MHz

0 1 0: 2 20 11.5 MHz

0 1 1: 2 25 14.2 MHz

1 0 0: 2 30 16.5 MHz

1 0 1: 2 35 20.0 MHz

1 1 0: 3 45 20.0 MHz

1 1 1: 3 55 20.0 MHz (default)

___________________________

1. The Settling and Compare periods are in clock cycles.

2. Conversion step time is equal to Settling Period + Compare Period

3Reserved.

5-4 T0DIV (Trigger Signal Division Factor). Controls the division of the T0IN trigger signal in Low Power Threshold

Comparison mode. A higher division factor gives a lower power consumption in Idle operation mode (see

Section 4.17 on page 235). T0IN frequency is separately set (see Section 4.10 on page 164).

Bits

5 4 T0In Division Factor

0 0: 16

0 1: 32

1 0: 64

1 1: 128 (default)

7-6 Reserved.

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Comparison Threshold Data Register (THRDAT)

This register holds the data used by the D/A converter in the threshold comparison modes. ACMCNF is cleared (0016)on

reset.

Location: 00 FD4616

Type: R/W

Comparison Result Register (CMPRES)

This register contains the result of the input comparison with the threshold.

Location: 00 FD4816

Type: RO

Bit 76543210

Name Reserved THRSHD5-THRSHD0

Reset 00000000

Bit Description

5-0 THRSHD5-THRSHD0 (Comparison Threshold Data). Data to be used by the D/A converter in Threshold

Comparison Burst and Low Power Threshold Comparison modes. All eight inputs are compared with the resulting

voltage value.

Range: 0 to 63 (0 to 63/64 *VCC); 6-bit, unsigned value with 1 LSB = VCC/64 (the value at reset is 0).

7-6 Reserved.

Bit 76543210

Name CMPIN7 CMPIN6 CMPIN5 CMPIN4 CMPIN3 CMPIN2 CMPIN1 CMPIN0

Bit Description

0CMPIN0 (Comparison Result for Input 0). Result of KBSIN0 comparison with the voltage threshold value.

Relevant only in Threshold Comparison Burst mode (ACMMOD = 102in ACMCNF register) and Low Power

Threshold Comparison mode (ACMMOD = 112). The value at reset is undeﬁned.

0: Input below threshold

1: Input above threshold

1CMPIN1 (Comparison Result for Input 1). Same as CMPIN0 for KBSIN1.

2CMPIN2 (Comparison Result for Input 2). Same as CMPIN0 for KBSIN2.

3CMPIN3 (Comparison Result for Input 3). Same as CMPIN0 for KBSIN3.

4CMPIN4 (Comparison Result for Input 4). Same as CMPIN0 for KBSIN4.

5CMPIN5 (Comparison Result for Input 5). Same as CMPIN0 for KBSIN5.

6CMPIN6 (Comparison Result for Input 6). Same as CMPIN0 for KBSIN6.

7CMPIN7 (Comparison Result for Input 7). Same as CMPIN0 for KBSIN7.

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Voltage Level Data Buffer - Input 0 through 7 (VOLDAT0-7)

This register holds the voltage level measurement result for inputs 0 through 7.

Location: 00 FD5016 - Input 0

00 FD5216 - Input 1

00 FD5416 - Input 2

00 FD5616 - Input 3

00 FD5816 - Input 4

00 FD5A16 - Input 5

00 FD5C16 - Input 6

00 FD5E16 - Input 7

Type: RO

4.14.6 Usage Hints

Voltage Level Burst

The total duration of the Voltage Level Burst measurement is a function of the system clock frequency (see Section 4.18 on

page 239) and the data sampling delay, selected by SMPDLY field in ACMTIM register. The values in Table 28 should only

be used to evaluate the maximum duration of the measurement. Actual duration may be shorter, depending on the input

level value. The software should use either EOMEV flag polling or the ACM interrupt, as described in Section 4.14.4 on

page 210.

Table 28. Voltage Level Burst Duration

Bit 76543210

Name Reserved VOLTLVL

Bit Description

5-0 VOLTLVL (Voltage Level Data). Voltage level of the respective input i (KBSINi for i 0 through 7), while operating

in Voltage Level Burst mode (ACMMOD = 012in ACMCNF register). The readout is an unsigned value with

1 LSB = VCC/64; the input voltage is calculated as: VIN = VOLTVL *(VCC/64).

7-6 Reserved.

System Clock Frequency

(MHz) SMPDLY Setting Maximum Burst Duration

(µs)

4 000 176

10 010 140

20 101 118

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4.15 ON-CHIP RAM

The PC87591x provides up to 4096-byte on-chip RAM array (2048-byte in PC87591E and PC87591L devices).

A 16-bit wide data bus links the core and the system RAM array. The system RAM can be byte or word accessed. Each

system RAM read or write operation is one cycle long and does not include any wait states. See Section 1.5.1 on page 33

for system RAM memory map.

4.16 ON-CHIP FLASH

The PC87591x has an on-chip flash memory device. This flash includes a Main Block, which serves as an on-chip Base

Memory, and an Information Block, which is used for device-specific parameters and user-defined data.

The Main Block (Base Memory) is used to store program and constant data of the core and/or host. In IRE and OBD envi-

ronments, the on-chip flash is used as (on-chip) Base Memory. In DEV environment, for easy and efficient code develop-

ment,theon-chipBase Memory is replaced by off-chip SRAM, which is referred to as off-chip Base Memory. See Section 1.4

on page 29 for more details about the memory emulation concept.

Note that in the PC87591L, the on-chip base memory is set to function as a ROM, with the associated limitations on write

and erase operations.

4.16.1 Features

●Two ﬂash memory blocks:

—Main Block (Base Memory)

—Information Block

●Designated areas for:

—Core boot code

—Host boot code

—Factory Parameters

—Protection information

●Supports ﬂash operations:

—Read (byte/word)

—Write (byte/word)

—Erase (page)

●Several access paths for ﬂash operations:

—Core

—Host

—JTAG

—Parallel Interface

●Flash contents protection:

—Different levels for each access path

—Different levels for each memory block

●Flash Timing Control for:

—Command-based automatic control

—Busy and error indicators

●Low Power operation

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4.16.2 Functional Description

The flash is byte accessible for reads and writes; it is erased in pages. Its organization is optimized for the PC87591x target

application and security needs. Table 29 summarizes the various flash size parameters.

Table 29. PC87591x Flash Organization

Flash Protection

The flash is partitioned into separate areas to protect the contents. Section 4.16.6 on page 226 provides details of the Main

Block and Information Block protection mechanisms, respectively. The main protected areas are:

●Main Block

—Core Boot Block - an area dedicated for the core boot code and protected from corruption by the CR or host.

—Host Boot Block - an area dedicated for host boot code and protected from corruption by the host.

—Other parts - optionally protected by software

●Information Block

—Factory Parameters - hold various parameters and calibration information deﬁned during PC87591x production; pro-

tected from all alterations.

—Protection Word - information about the ﬂash data protection that may restrict accessing, writing and/or erasing all or

parts of the ﬂash.

—Other parts - software-controlled read and write protection.

Main Block (Base Memory) Information Block

Size1

1. See “Accessing Base Memory” on page 35 for the mapping of the memory blocks in the core address space.

Organization2

2. The memory width should be used for correct conﬁguration of the BIU to enable cycle-by-cycle compatibility

between on-chip and off-chip Base Memory.

Page Size Access

Width AccessTime

Control Size Page Size Access

Width

64 Kbytes3

3. Block Size is 4 Kbytes only in PC87591L devices.

32Kx16

(Section 0) 512 bytes byte/word SZCFG1 64x16

(Section 0) 128 bytes byte/word

64 Kbytes4

4. This Main Block is available in PC87591S devices only.

32Kx16

(Section 1) 512 bytes byte/word SZCFG1 64x16

(Section 1) 128 bytes byte/word

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Access Paths

The flash memory can be read, written and erased through several access paths with different levels of protection for the

flash contents. Each of these paths can be operational in only some of the environments (i.e., IRE, OBD, DEV or PROG).

The flash access paths are:

●Host interface

●CR16B core

●JTAG ﬂash access

●Parallel interface

Thehostand core use core bus read write transactions to access the flash. The JTAG and Parallel Interfaces have dedicated

access paths. An arbitration scheme selects the active interface that accesses the flash at any given time. The host and core

accesses may interleave. JTAG flash access is enabled in OBD and ENV environments when the appropriate enable bits

are set (see “Flash Interface Functional Description” on page 251 for the access enabling scheme). The Parallel interface

is enabled in PROG environment only.

Table 30 summarizes the flash information accessibility, the restrictions that apply in the various environments and the pro-

tection bit settings for each of the memory areas. Details of read, write and erase access are provided in Section 4.16.4 on

page 224. The following notation is used:

NA - Not accessible

RO - Read only

RW - Read, Write

RWE - Read, Write and Erase

RWe - Read, Write and a limited Erase (i.e., entire flash erase only).

Figure 76. On-Chip Flash Block Diagram

Arbitration

Protection

Timing

Access

Control

Shared BIOS

and

Security

Core Bus

JTAG I/F

Parallel I/Fs

Core

Main Block Information Block

To Host

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Table 30. PC87591x Flash Read/Write/Erase Permission Matrix

Flash Page Organization and Erase Options

A flash erase operation changes all bits in the erased memory area to 1s. The minimum flash portion that can be erased is

a page. A byte address can be written once before the next erase.

The erase process includes verification. During an erase, a busy indicator is turned on. On completion, the busy indicator is

turned off, an error indicator is turned on if an error is detected and the on-chip flash returns to standby.

A flash program operation changes bits that are 1 to 0. A flash program operation may performed on bytes or words.

The PC87591x flash is organized in rows, grouped in pages and partitioned into sections as follows:

Table 31. PC87591x Section and Page Organization

The PC87591x provides three erase operations:

●Page Erase - erase either one page of the ﬂash Main Block or Information Block.

●Section Erase - erase an entire section.

●Special Erase - erase the entire ﬂash (except factory parameters).

Notes:

●The high voltage required for ﬂash operation is generated on-chip from VCC.

●Flash endurance: 10,000 write-erase cycles (minimum).

The PC87591L ﬂash is guaranteed for ﬁve write-erase cycles only.

●Data retention: more than 100 years at room temperature.

Memory Area Interface Host1

1. Additional read and/or write protection may apply according to the setting of the software

controlled protection mechanism.

Core JTAG2

2. Read and write operations are enabled only if the Flash Access Enable bit (FLAEN in

FL_CT_ST register) is 1 (see page 262). When the Flash Access Enable bit is cleared,

only a special erase may be performed.

Parallel I/F2

Environment IRE, OBD & DEV OBD & DEV PROG

Main Block

(Base Memory) Core Boot Block NA3

3. In DEV Environment, the Base Memory is implemented using an off-chip SRAM, thus any

access by the core and/or host is routed to it. Host access limitations apply in DEV envi-

ronment. The core is allowed full read and write access to the off-chip Base Memory.

RO3RWE RWE

Host Boot Block RO3RWE3RWE RWE

Other RWE3RWE3RWE RWE

InformationBlock Factory Parameters NA RO RO RWE

Protection Word NA RO RWe RWe

Block Section Name Address Range Page Size

Main Block Section 01

1. In the PC87591L, the main block is in addresses 00 000016 - 000FFF16.

00 000016 - 00 FFFF16 512 bytes

Section 12

2. Available only in the PC87591S.

01 000016 - 01 FFFF16 512 bytes

Information Block Section 0 00016 - 07F16 128 bytes

Section 1 08016 - 0FF16 128 bytes

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Flash Read, Write and Erase Time

The flash read access time affects the performance of the core. It is therefore recommended to configure the interface to

achieve the maximum performance allowed for the operation frequency. Table 32 lists the access time for each section of

the flash.

Notes:

●Write cycle timing is not cycle-by-cycle emulated for off-chip Base Memory (SRAM).

●For fast read operation, the respective BIU zone should be conﬁgured for fast read.

●For n wait states, the respective BIU zone should be conﬁgured for normal read with n wait states. This provides an

n+2 cycles read throughput.

●Sections 0 and 1 are also referred to as the Fast zone.

The Flash Timing Control, included as part of the PC87591x on-chip flash, controls the access time for read, write and erase

operations of the flash memory. This simplifies the handling and use of the flash by the user. To enable operation with var-

ious clock rates the Flash Timing Control includes a set of registers that enable the core to set the parameters. For more

details on the Flash Timing Control, see Section 4.16.3 on page 222.

4.16.3 Flash Interface States and Timing Control

The Flash Timing Control automates six states: Standby, Read, Program, Page Erase, Section Erase and Special Erase.

The widths of pulses used in flash operation are specified in registers and should be set by software based on the operation

frequency of the core clock.

●Standby State

The ﬂash does not perform a read, program or erase operation. This is the default state when no operation is per-

formed; current consumption of the ﬂash is therefore minimal.

●Read State

The ﬂash performs a read operation from either the Main Block or the Information Block. Host or core reads

through the core bus are extended to the required length based on the BIU SZCGF1settings. JTAG interface ac-

cess uses a busy ﬂag to indicate that the read operation is in progress. When the read is completed, the ﬂash re-

turns to Standby state.

●Program State

The ﬂash programs a byte or word in either the Main Block or Information Block. This state is entered by a core or

host write (with the Program control bit set) or by a JTAG program command. While in this state, the busy indicator

is set. When the program operation is completed, if the verify is enabled, the data is veriﬁed and the error bits are

updated accordingly. During Program state, reset is ignored. During programing of the ﬂash, additional writes to

the ﬂash are ignored and reads are delayed until the ﬂash page programing is completed.

●Page Erase State

The Page Erase state is entered by a core or host write or by a JTAG command when the Page Erase bit is set. An

address within the page speciﬁes which page is to be erased. While in this state, the busy indicator is set. When

the erase operation is completed and the veriﬁcation is enabled, the data is veriﬁed and the error bits are updated

accordingly. During Page Erase state, reset is ignored, additional writes to the ﬂash are ignored and reads are de-

layed until the ﬂash page erase is completed.

●Section Erase State

The Section Erase state is entered by a core write or by a JTAG command when the Section Erase bit is set. An

address within the section speciﬁes which section is to be erased. While in this state, the busy indicator is set.

When the erase operation is completed, the data is veriﬁed and the error bits are updated accordingly. During Sec-

tion Erase state, reset is ignored, additional writes to the ﬂash are ignored and reads are delayed until the ﬂash

section erase is completed.

Table 32. Access Time for Flash Sections

Block Name Section Number Max Frequency1,2

1. See Section 7.5 on page 381 for the values of these parameters.

2. The Zone Conﬁguration register SZCFG1 should be used to set the access speed, based on the cur-

rent operation speed and minimum required access time.

Write Time Erase Time

Main Block Sections 0 and 1 FFMAX @ fast read Approx. 20 µs,

as deﬁned in Table 33 Approx. 10 ms,

as deﬁned in Table 33

Information Block Sections 0 and 1 FFMAX @ 3 clock cycles Approx. 10 ms,

as deﬁned in Table 33

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A write to an address within a Main Block section results in an erase of the Main Block section. A write to an ad-

dress within an Information Block section results in an erase of the Information Block section and its corresponding

Main Block section (e.g., Main Block section 0 and Information Block section 0).

●Special Erase State

The Special Erase state is entered by a command from JTAG. Special erase enables erasing the entire ﬂash, ex-

cept for the factory parameters. It is the only operation on the ﬂash enabled for the JTAG when the ﬂash protection

ﬁeld is set to Protect. While in this state, the busy indicator is set. When the erase operation is completed, the data

is veriﬁed and the error bits are updated accordingly. During Special Erase state, reset is ignored. The protected

data information is always the last to be erased.

Both program and erase can be initiated by the host, core or JTAG interface. Note that no instruction fetch or data read/write

can be performed from/to the on-chip flash while it is being programed or erased.

While the JTAG Flash interface is enabled, the Debugger interface generates a reset, which causes the core, the Host in-

terface circuit and the core bus to be held in reset.

Flash Operation Timing Control

The Information Block read, the program and erase timings are controlled by internal timers. (The read timing from the Main

Block is controlled by the BIU configuration). The timers default on Power-Up reset to operate at a core frequency of 4 MHz.

Software may change this for operation with other core clock frequencies.

Section 4.16.7 on page 228 lists the timing control registers. Table 33 provides the values that should be programed into

the control registers for each core domain clock frequency. It is the responsibility of the firmware to make sure that the timing

control registers are set according to the current core domain clock frequency before any flash erase or flash program is

allowed.

Reset

While the on-chip flash is in Read state, driving reset aborts the current operation. Flash program and Erase operations con-

tinue to completion and the reset is extended accordingly. If reset is applied during Program or Erase state, the contents of

memory are not guaranteed (i.e., the program or erase may fail).

After reset, the on-chip flash defaults to Standby state.

When JTAG access to flash is disabled, the Flash interface is reset by all reset events. When the JTAG access to flash is

enabled, the PC87591x is reset, but the Flash interface allows flash access after all of the following have occurred:

●The core clocks are stable in their default setting.

●The protection information has been read.

●Default values have been loaded into the Flash Interface registers.

On exiting from “JTAG Access to Flash” mode, the Flash Interface module is reset again (i.e., protection information is read

and default values loaded into the Flash Interface registers)

Table 33. Control Registers Values per Core Domain Clock

Core Domain

Clock FLPSLR FLSTART FLTRAN FLPROG FLPERASE FLSERASE FLEND FLSEND FLRCV

[MHz] [hex] [hex] [hex] [hex] [hex] [hex] [hex] [hex] [hex]

4 0 14 28 A 9 9 14 32 4

5 0 19 32 C C C 19 3E 5

6 0 1E 3C F E E 1E 4B 6

7 0 23 46 11 11 11 23 57 7

8 0 28 50 14 13 13 28 64 8

9 0 2D 5A 16 16 16 2D 70 9

10 1 19 32 C C C 19 3E 5

12 1 1E 3C F E E 1E 4B 6

20 3 19 32 C C C 19 3E 5

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Pipelined Programing Cycles

Pipelined programing uses a word-wide double-buffer (for Main Block accesses) or a byte-wide double-buffer (for Informa-

tion Block accesses). Accesses should be word-wide or byte-wide, correspondingly; otherwise, results are undefined.

When the double-buffer is empty, the pipelined programing is initiated on a valid byte/word write to the on-chip flash. The

address of the transaction is the starting address. The Flash Timing Control automatically increments the address for the

next write to point to the next byte/word.

Pipelined programing is completed when the double-buffer is empty or on reaching the highest address within the row. On

completion, the busy indicator is turned off, any data in the double-buffer is discarded, an error indicator is turned on if an

error is detected, and the on-chip flash returns to standby.

Results are undefined when Main Block and Information Block accesses are interleaved while the double-buffer is notempty.

Low Power Read Operation Mode

The PC87591x supports low power read operation for the on-chip flash. When this is enabled (see “Flash Memory Control

enabled only when the core clock is below the following limit:

●Below FMAX for Sections 0 and 1 controlled by LOWPWRF bit

4.16.4 Flash Access and Control

The flash may be accessed for read, program and erase of data in either the Main Block or Information Block. This section

describes the activities required to enable any of the operations from each of the access paths (Core, Host, JTAG).

Before an access path to the flash may be used, the PC87591x must be in a state that enables that path:

●Core and Host Interface - Active in IRE, OBD or DEV environment (Information Block only for DEV environment).

For host write operations, the host must gain control of the ﬂash (HLOCK bit in SMCCST register must be set).

Any access (read or write) protection may override the requested access.

●JTAG Interface - OBD or DEV environments with the JTAG Flash interface enabled.

Section 4.19 on page 248 provides details of the JTAG flash access. Section 4.16.5 on page 226 provides details of the

PROG environment bus. For all interfaces, read, program and erase protection flags may prevent the operations described

from being completed.

Note that during Erase and Program of the flash, an access to the flash is handled as follows:

●Core read is delayed to the end of the read.

●Core write to the Main Block or Information Block is ignored.

●Core write to IBAI register is ignored.

●Host reads or writes are ignored by the Flash interface and restarted by the host once the ﬂash program/erase is

completed.

If core activity is required during flash program or erase, make sure it executes from RAM or external memory before the

flash erase/programing begins.

Main Block Read

When the flash is not busy, read operations return the data in the accessed on-chip flash address. Either byte or word may

be read.

The SZCFG1 register defines the number of core bus cycles used to access Base Memory (see Section 4.1.11 on page 86

and “Static Zone Configuration Register (SZCFGn)” on page 85 for further details). The number of cycles that each access

requires, for each one of the zones, is defined in “Flash Read, Write and Erase Time” on page 222.

If the BIU configuration is identical in all environments, the access time to the on-chip flash Main Block and off-chip Base

Memory, for read operations, is the same. This allows cycle-by-cycle compatibility in IRE, OBD and DEV operating environ-

ments.

Information Block Read

Information Block data is read using an indirect access scheme. This information may be read by the core, through the JTAG

Interface or the Parallel Interface.

The core accesses the Information Block using indirect byte/word read access. To read from the Information Block:

●The byte or word address must be stored in IBAI register (note that Information Block addresses are mapped from

000 as shown in Table 31 on page 221).; word addresses must be even.

●Data byte/words must be read using a byte/word read operation from BD register.

The JTAG performs a read operation with an Information Block address attribute set. Only word read is allowed.

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Main Block Page Erase

Pages in the Main Block may be erased one at a time. The size of the pages are defined in Table 30 on page 221 and “Flash

Read, Write and Erase Time” on page 222. To enable erasing by the core or host, the page must be enabled for write.

1. Verify that the flash is not busy.

2. Prevent access to the flash while erase is in progress, if required.

3. Set the page erase bit.

4. Write to an address in the desired page.

5. Wait until the busy bit is cleared and check the error flags to see if the erase was successful.

6. To erase additional pages, repeat steps 3 through 5.

7. Clear the page erase bit to prevent accidental erase operations.

To erase a page using the JTAG interface, see Section 4.19.4 on page 251.

Information Block Page Erase

Pages in the Information Block may be erased one at a time. The size of the pages are defined in Table 30 on page 221 and

Table 31 on page 221. Note that the factory parameters and the protection information may not be updated by the core.

To erase a page using the JTAG interface, see Section 4.19.4 on page 251. Note that the Factory Parameters page may

not be erased by the JTAG interface.

Main Block Section Erase

Sections in the Main Block may be erased with a single erase operation. The size of the sections are defined in Table 30 on

page 221 and Table 31 on page 221. To enable an erase by the core, the entire section must be enabled for write. Note that

Host-initiated section erases are not allowed.

1. Verify that the flash is not busy.

2. Prevent access to the flash while erase is in progress, if required.

3. Set the section erase bit in the control register (SMER bit in FLCR register).

4. Write to an address in the desired section.

5. Wait until the busy bit is cleared and check the error flags to see if the erase was successful.

6. To erase additional sections, repeat steps 3 through 5.

7. Clear the section erase bit (SMER bit in FLCR register) to prevent accidental erase operation.

To erase a page using the JTAG interface, see Section 4.19.4 on page 251.

Main and Information Block Section Erase

Sections in the Main Block and Information Block may be erased simultaneously using a single erase operation. The size of

the sections are defined in Table 30 on page 221 and Table 31 on page 221. To erase a section using the JTAG interface,

see Section 4.19.4 on page 251.

Special Erase

This operation is enabled only for the JTAG interface. If the Flash Contents Protection bit is set, this operation should be

done to enable any other access to the flash (or to enable the Debugger interface functions).

To perform a special erase using the JTAG interface, see Section 4.19.4 on page 251.

Program the Main Block

The program operation enables changing bits with a value of 1 to 0. Each byte address of the Main Block may be programed

once before being erased. If required, perform an erase operation prior to the program operation. To program a byte in the

Main Block:

1. Verify that the flash is not busy.

2. Prevent access to the flash while the program operation is in progress, if required.

3. Set the program bit in the control register (PE bit in FLCR register).

4. Write to the byte or word that needs to be programed.

5. Wait until the busy bit is cleared and check the error flags to see if the program operation was successful.

6. To program additional bytes/words, repeat steps 3 through 5.

To program a byte or word using the JTAG interface, see Section 4.19.4 on page 251.

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Program a Page in the Information Block

The program operation enables changing bits with a value of 1 to 0. Each byte address of the Information Block may be

programed once before being erased. If required, perform an erase operation prior to the program operation.

To program a word using the JTAG interface, see Section 4.19.4 on page 251.

4.16.5 Parallel Flash Interface

The Parallel Flash interface used in PROG environment allows the PC87591x to be tested and programed quickly with Au-

tomated Test Equipment (ATE) and programers in the OEM’s manufacturing flow.

For details about this interface, contact a National Semiconductor sales representative.

4.16.6 Flash Protection

The Main Block can be accessed by the core, host, JTAG interface and Parallel interface. The Information Block may be

accessed by the core, JTAG interface and Parallel interface. A protection mechanism that combines hardware and software

controlled elements is provided. The protection level depends on the access path used and the contents of the ‘protection

word’.

Protection Word

The protection word is stored in address 0FE16 in the flash Information Block. It is constructed as follows:

Bit 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Name Res RST2EN Reserved Flash Contents

Protect

Force

MBTA

Zero

RTC Lock

Default Host Boot

Block Core Boot Block

Bit Description

3-0 Core Boot Block. Deﬁnes the size of the Core Boot Block

The boot block starts at address 00 0000 and ends at the address speciﬁed by this ﬁeld.

Bits

3 2 1 0 Description

1 1 1 1: Flash is erased. When in IRE and OBD environments, the core is kept in reset (default).

1 1 1 0: 4K

1 1 0 1: 8K

1 1 0 0: 16K

1 0 1 1: 24K

1 0 1 0: 32K

1 0 0 1: 40K

1 0 0 0: 48K

0 1 1 1: 56K

0 1 1 0: 80K

0 1 0 1: 96K

0 1 0 0: 112K

0 0 1 1: 128K

Other: Reserved

4Host Boot Block. Deﬁnes the use and the size of a Host Boot Block area. The Host Boot Block is always at

the end of the on-chip ﬂash memory. Protection is provided by the Shared Memory function.1

0: A 64 Kbyte Host Boot Block is specified

1: No Host Boot Block is available (default)

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The protection word is read by hardware from the Information Block during the internal reset process. This information is

used to set the host access restrictions described in Section 5.3.5 on page 301, the core access restrictions defined in this

section, and the JTAG access protection described in OBD and PROG environment access restrictions; see Table 30 on

page 221.

There is no protection over the core’s reading the flash contents. Writes to a write-protected page are ignored. When en-

abled, a core interrupt may be generated on write-protect violations.

Core-Initiated Accesses

There is no read protection on core-initiated read accesses. Write protection is provided with default settings and firmware

override as follows:

●Main memory block - per 8 Kbyte block

●Information Block Factory parameters and protection word are always write protected

This protection is deﬁned using FCWP0 register. All blocks are deﬁned as write protected on reset. The blocks within the

Core Boot Block and Host Boot Block are read only (RO) to prevent accidental alteration of their contents by the core.

Special Erase state is not supported for core-initiated accesses.

Host-Initiated Accesses

Host access to the flash Main Block is controlled by the information in the protection word and is controlled and further re-

stricted by the core. Section 5.3.5 on page 301 details the host access limitations. The host may not access the Information

Block.

5RTC Lock Default. Deﬁnes the reset value of the Lock RTC Host Access (LKRTCHA) bit in the Lock SuperI/O

Host Access register (LKSIOHA). This enables preventing host access to the RTC at any time when the RTC is

used by security applications running on the core.

0: RTC Lock is disabled on reset (LKRTCHA=0)

1: RTC Lock is enabled on reset (LKRTCHA=1) (default)

6Force MBTA Zero. Enables the setting of the host boot block location to either end of on-chip ﬂash or to the

expansion memory1. See “Shared Memory Core Top Address Register (SMCTA)” on page 308.

0: MBSD field in SMCTA register is reset to the implemented on-chip flash size

1: MBSD field in SMCTA register is reset to 000016 (default)

9-7 Flash Contents Protect. Enables protecting the contents of the on-chip ﬂash from probing through the JTAG

interface or Parallel interface.

Bits

9 8 7 Description

1 1 1: Flash access is enabled for both read and write

Other: Flash access is protected. In any environment other than IRE, the device remains reset.

In OBD and DEV environments, only

special erase through the JTAG interface is enabled.

12-10 Reserved.

14-13 RST2EN (RESET2 Enable). Controls the use of the RESET2 alternate function. The following options are

supported in the PC87591x:

Bits

15 14 Description

0 0: Reserved

0 1: RESET2 is enabled on the IOPB7/RING/PFAIL/RESET2 pin

1 0: RESET2 is enabled on the IOPD2/EXWINT24/RESET2 pin

1 1: RESET2 input is disabled, and RESET2 events will not be generated (default)

15 Reserved.

1. When expansion memory is used for a shared BIOS implementation, set the Force MBTA Zero bit to 0, do not

clear the Host Boot Block bit, and use a ﬂash device with a boot block as expansion memory.

Bit Description

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JTAG-Initiated Accesses

JTAG-initiated accesses for both read and write is restricted based on the value held in the Flash Contents Protect field of

the protection word.

When any bit in the Flash Contents Protect field is 0, no reads or writes are allowed. In OBD or DEV environment, the device

remains reset until a special erase is performed. The only operation allowed in this case is a special erase of the flash con-

tents.

When all bits in the Flash Contents Protect field are 1, all flash operations are allowed. The entire flash may be read, and

except for the Factory Parameters page Of the Information Block, the entire flash may be erased and programed.

Parallel Flash Interface-Initiated Accesses

Parallel Flash interface-initiated accesses are subject to the same protection scheme as JTAG-initiated accesses. When

any bit in the Flash Contents Protect field is 0, only special erase operations are allowed and all other flash access opera-

tions are ignored.

See also Section 4.16.5 on page 226.

4.16.7 Flash Interface Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

Information Block Access Index Register (IBAI)

This register defines the address bits 7-0 for read or write transaction to the Information Block.

Location: 00 F88016

Type: R/W

Table 34. Flash Interface Register Map

Mnemonic Register Name Type

IBAI Information Block Access Index R/W

IBD Information Block Data R/W

FCWP0 Flash Core Write Protect R/W

FLCR Flash Memory Control R/W

FLSR Flash Memory Status R/W1C

FLPSLR Flash Memory Pre-Scaler R/W

FLSTART Flash Memory Start Time R/W

FLTRAN Flash Memory Transition Time R/W

FLPROG Flash Memory Program Time R/W

FLPERASE Flash Memory Page Erase Time R/W

FLSERASE Flash Memory Section Erase Time R/W

FLEND Flash Memory End Time R/W

FLSEND Flash Memory Section Erase End Time R/W

FLRCV Flash Memory Recovery Time R/W

Bit 1514131211109876543210

Name Reserved Indirect Memory Address 7-0

Bit Description

7-0 Index Address 7-0. The address is of a byte address in the ﬂash Information Block. Access to words is allowed

only to word-aligned addresses.

15-8 Reserved.

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Information Block Data Register (IBD)

This register holds the data for read or write transaction from/to the Information Block. Byte or word reads and writes to this

register are allowed to access a byte or word pointed to by IBA register. Note the program and erase limitations imposed by

the flash protection scheme.

Location: 00 F88216

Type: R/W

Flash Core Write Protect Register 0 (FCWP0)

This register controls write protection of the Main Block per 8 Kbyte blocks. It is cleared (0016) on reset.

Location: 00 F89016

Type: R/W

Bit 1514131211109876543210

Name Information Block Data

Bit Description

15-0 Information Block Data.

Bit 1514131211109876543210

Name FC0WP15-0

Reset 0000000000000000

Bit Description

15-0 Core Write Protect. Each bit controls an 8 Kbyte block.

For bit i, the block’s start address is i x 00 200016.

0: Program and erase are inhibited for this block

1: Program and erase are allowed for this block

Bits within the Core Boot Block and Host Boot Block, as deﬁned by the protection word, are ignored, and the

ﬂash memory is always write protected.

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Flash Memory Control Register (FLCR)

This register controls the on-chip flash operation modes. It is cleared (0016) on reset. The core can write this register only

when HLOCK bit in SMCCST register is 0 (see Section 5.3.9 on page 307). Otherwise, writes are ignored.

Location: 00 F8C016

Type: R/W

Bit 76543210

Name SMER PMER PE IENPROG Reserved LOWPWR

Reset 00000000

Bit 15 14 13 12 11 10 9 8

Name Reserved DISVRF

Reset 00000000

Bit Description

0LOWPWR (Low Power Mode).

0: On-chip flash is in Normal mode

1: On-chip flash is in Low Power mode

This bit may be set (1) only when the core domain’s clock is up to fFLPMAX.

It may be altered only when FRE bit in SZCFG1 register is set (1).

3-1 Reserved.

4IENPROG (Interrupt Enable for Program).

0: Interrupt request disabled.

1: An interrupt request to the ICU is enabled (see FMLFULL in the Flash Memory Status register).

5PE (Program Enable). This bit is impact core program operations only.

0: Flash Programing is disabled (default)

1: Flash Programing is enabled (if PMER and SMER are cleared)

6PMER (Page Erase). When set (1) a valid write to the on-chip flash erases the entire page pointed to by the

write address. This bit affects core erase operations only.

This bit may be modiﬁed, only when the FMBUSY bit is cleared (0); otherwise, results are undeﬁned.

0: Flash Page Erase is disabled (default)

1: Flash Page Erase is enabled (if PE and SMER are cleared).

7SMER (Section Erase). When set (1), a valid write to the on-chip ﬂash erases the entire section pointed to by

the write address.

Write to a Main Block address results in a Main Block section erase.

Write to an Information Block address results in an Information Block section and its corresponding Main Block

section erase. This bit affects core erase operations only.

This bit may be modiﬁed only when the FMBUSY bit is cleared (0); otherwise, results are undeﬁned.

0: Flash Section Erase is disabled (default)

1: Flash Section Erase is enabled (if PMER and PE are cleared).

8DISVRF (Disable Verify). This bit affects core program and erase operations only.

0: Verify flash contents after program or erase is enabled (default).

1: Disable the automatic verification of flash contents after program or erase.

This speeds up the program or erase speed.

15-9 Reserved.

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Flash Memory Status Register (FLSR)

This register provides the on-chip flash status. It is cleared (0016) on reset.

Location: 00 F8C216

Type: Varies per bit

Flash Memory Pre-Scaler Register (FLPSLR)

The FLPSLR register selects the pre-scaler divider ratio. FLPSLR defaults to (0016) on reset.

Location: 00 F8C416

Type: R/W

Bit 76543210

Name Reserved DERR FMLFULL FMBUSY PERR EERR

Reset 00000000

Bit Type Description

0 R/W1C EERR (Erase Error). Indicates an error in erasing the ﬂash by the core. It is cleared by writing 1 to it.

Writing 0 is ignored. This bit may be cleared only when the FMBUSY bit is cleared (0).

0: No program error detected (default)

1: An error occurred during erase

1 R/W1C PERR (Program Error). Indicates an error in writing to the ﬂash by the core. It is cleared by writing 1

to it. Writing 0 is ignored. This bit may be cleared only when the FMBUSY bit is cleared (0).

0: No program error detected (default)

1: An error occurred during program

2ROFMBUSY.

0: The embedded flash is ready to accept operations

1: The embedded flash is not accessible since the PC87591x clocks are not ready or the embedded flash

is busy programing or erasing

3ROFMLFULL (Double-Buffer Full). Indicates that the core can not write to the ﬂash since its buffer is full.

0: There is at least one word empty in the flash double buffer. If IENPROG is set (1), in the Flash Memory

Control register, an interrupt request to the ICU is active.

1: The double-buffer is full

4 R/W1C DERR (Data Loss Error). Indicates that a double-buffer overrun error has occurred during core access.

It is cleared by writing 1 to the DERR bit. Writing 0 is ignored. This bit may be cleared only when the

FMBUSY bit is cleared (0).

0: No data loss detected (default)

1: A write to a full buffer was detected

7-5 Reserved.

Bit 76543210

Name Reserved FTDIV

Reset 00000000

Bit Description

3-0 FTDIV (Pre-Scaler Divider Value). This register should be configured based on the currently set core

frequency. See Table 33 on page 223 for details of required values.

7-4 Reserved.

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Flash Memory Start Time Register (FLSTART)

The FLSTART register controls the program/erase start delay time. FLSTART defaults to (1416) on reset.

Location: 00 F8C616

Type: R/W

Flash Memory Transition Time Register (FLTRAN)

The FLTRAN register controls some program/erase transition timings. FLTRAN defaults to (2816) on reset.

Location: 00 F8CA16

Type: R/W

Flash Memory Program Time Register (FLPROG)

The FLPROG register controls the programing pulse width. FLPROG defaults to (0A16) on reset.

Location: 00 F8D016

Type: R/W

Bit 76543210

Name FTSTART

Reset 00010100

Bit Description

7-0 FTSTART (Start Delay Count). This register should be configured based on the currently set core frequency.

See Table 33 on page 223 for required values.

Bit 76543210

Name FTTRAN

Reset 00101000

Bit Description

7-0 FTTRAN (Transition Count). This register should be configured based on the currently set core frequency. See

Table 33 on page 223 for details of required values.

Bit 76543210

Name FTPROG

Reset 00001010

Bit Description

7-0 FTPROG (Programing Pulse Width). This register should be configured based on the currently set core

frequency. See Table 33 on page 223 for details of required values.

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Flash Memory Page Erase Time Register (FLPERASE)

The FLPERASE register controls the page erase pulse width. FLPERASE defaults to (0916) on reset.

Location: 00 F8D216

Type: R/W

Flash Memory Section Erase Time Register (FLSERASE)

The FLSERASE register controls the section erase pulse width. FLSERASE defaults to (0916) on reset.

Location: 00 F8D416

Type: R/W

Flash Memory End Time Register (FLEND)

The FLEND register controls the program/page erase end delay time. FLEND defaults to (1416) on reset.

Location: 00 F8D816

Type: R/W

Bit 76543210

Name FTPER

Reset 00001001

Bit Description

7-0 FTPER (Page Erase Pulse Width). This register should be configured based on the currently set core

frequency. See Table 33 on page 223 for details of required values.

Bit 76543210

Name FTSER

Reset 00001001

Bit Description

7-0 FTSER (Section Erase Pulse Width). This register should be configured based on the currently set core

frequency. See Table 33 on page 223 for details of required values.

Bit 76543210

Name FTEND

Reset 00010100

Bit Description

7-0 FTEND (End Delay Count). This register should be configured based on the currently set core frequency. See

Table 33 on page 223 for details of required values.

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Flash Memory Section Erase End Time Register (FLSEND)

The FLSEND register controls the section erase end delay time. FTSEND defaults to (3216) on reset.

Location: 00 F8DC16

Type: R/W

Flash Memory Recovery Time Register (FLRCV)

The FLRCV register controls the recovery time required between two accesses. FTRCV defaults to (0416) on reset.

Location: 00 F8DE16

Type: R/W

Bit 76543210

Name FTSEND

Reset 00110010

Bit Description

7-0 FTSEND (Section Erase End Delay Count). This register should be conﬁgured based on the currently set core

frequency. See Table 33 on page 223 for details of required values.

Bit 76543210

Name FTRCV

Reset 00000100

Bit Description

7-0 FTRCV (Recovery Time). This register should be configured based on the currently set core frequency. See

Table 33 on page 223 for details of required values.

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4.17 POWER MANAGEMENT CONTROLLER (PMC)

The Power Management Controller (PMC) module improves the efficiency of PC87591x operation by adjusting the chip’s

power consumption to the level of activity required by the application. This module works together with the High-Frequency

Clock Generator (HCFG) and the core to control the activity of the PC87591x. It also interacts with the Multi-Input Wake-Up

(MIWU), Interrupt Control Unit (ICU) and Debugger interface for wake-up events.

4.17.1 Features

●Three core domain power modes:

—Active

—Idle

—Power Off

●Two clock inputs:

—High-frequency clock (HFCLK)

—Low-frequency clock (LFCLK)

●Power mode switching by software and/or hardware control

●High-frequency clock source Enable/Disable control

●Other core domain modules are controlled with power mode indications

4.17.2 The Core Domain Power Modes

Table 35 summarizes the main properties of the three modes and shows the activity levels of clocks while in the various

power states.

Table 35. Core Domain Power Mode Summary

Active Mode

In Active mode, the core domain operates at the frequency generated by the HFCG. This frequency may be changed dy-

namically using the Load, Fast, Load96 or Fast96 operations in the HFCG module. The module’s respective enable/disable

bits control module activity.

In this mode, power consumption can be reduced by selectively disabling modules and/or by the core executing the WAIT

instruction. When WAIT is executed, the core stops executing new instructions until it receives an interrupt signal.

After reset, the PC87591x is in Active mode.

Idle Mode

In Idle mode, the clock is stopped for most of the core domain. Only the PMC and a limited number of core domain modules

(such as the TWD) continue to operate at the low-frequency oscillator rate; they can wake up the core domain and resume

instruction execution when required.

For modules that are active in Idle mode, details of their activity are included in the module’s description.

Wake-up events are generated by the MIWU module according to the enabled internal and external events.

Power Off Mode

When VCC power is turned off, the core domain reaches its lowest activity level. The contents of the memories (except for

the on-chip flash) and registers are not preserved in this mode. Applying power to the core domain should be done using

the VCC power-up reset sequence.

Mode HFCG LFCG CLK LFCLK1

1. The RTC and TWM modules always work from the LF oscillator.

VCC Supply

Active2

2. The core may execute the WAIT instruction while in Active mode to reduce power con-

sumption while no core activity is required. This state is referred to as “Active Executing

WAIT” in some places in the speciﬁcation, but it is not a separate power state as far as

clocks are concerned.

On On HF LF On

Idle On or Off3

3. Can be turned off by software but depends also on SuperI/O clock domain activation.

On Off LF On

Power Off Off On Off Off Off

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A battery supply pin (VBAT) provides power to the RTC and low-frequency clock oscillator (LFCO), allowing these parts to

continue functioning even in Power Off mode. Some registers are reserved and events recorded. These registers and events

are maintained by VPP, as noted.

Details of the activity of each battery-operable module are provided in the module’s specification.

4.17.3 Switching Between Power Modes

The switching from one power mode to another is done using the protocols described below.

Figure 77 shows the three power modes of the core domain and the transitions between them.

Wake-Up Event

Some of the power-up switchings are based on receiving a wake-up event. This event has three possible sources:

●A maskable event (from MIWU)

●A Non-Maskable Interrupt (NMI)

●An ISE interrupt (from the Debugger interface)

The wake-up is identified by a high level on the maskable event and/or a low-to-high transition on NMI or ISE interrupts.

Once a wake-up event is detected, it is latched until an interrupt acknowledge bus cycle is detected or a reset is applied.

Decreasing Power Consumption

Entering Idle Mode

Enter Idle mode by setting (1) IDLE bit in PMCSR register and then executing the WAIT instruction. WBPSM must be set

before executing WAIT.The HFCG may be disabled to further reduce the power consumption. This is done by writing 1 to

DHF in PMCSR register before executing WAIT.

Entering Power Off Mode

Switch to Power Off mode by turning off the supply to the VCC pins of the PC87591x Note that VDD must be turned off as well.

The PFAIL input may be used to interrupt the PC87591x so that context saving to a non-volatile memory can be completed

and write operations to the RTC can be stopped before the power to the PC87591x is disconnected.

Increasing Activity

Fast Wake-Up from Idle Mode to Active

Ahardwarewake-upevent causes the core domain to switch directly from Idle mode to Active mode. The following sequence

is performed:

1. HDF in PMCSR register is cleared, thus enabling the high-frequency clock (if it was disabled).

2. After waiting for the high-frequency clock to become active (OHFC in PMCSR register is set), the core domain switches

to Active mode.

When in Active mode, Idle bit in PMCSR register is cleared.

Active

Idle

Power Off

Turn off supply

IDLE =1

and WAIT

Turn on power

apply reset

HW event

supply and

Reset

Figure 77. Power Modes and Transitions

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If the core was executing a WAIT instruction, it resumes operation by entering an interrupt routine (an enabled interrupt in

the ICU, NMI or ISE).

Exit from Power Off

When in Power Off, activity can be resumed only by switching to Active mode. This is done by applying VCC power to the

PC87591x. The Power-Up reset sequence described in “VCC Power-Up Reset” on page 66 should be applied.

Power Mode Switch Protection

The PMC module includes a mechanism that protects the PC87591x from malfunctions caused by missing or unstable clock

signals.

Clock Toggling Indication

OHFC and OLFC bits in PMCSR register indicate the current status of the high- and low-frequency clock inputs, respectively.

The current status is based on indications from the HFCG and LFCG modules.

ThePMCdoesnotusethehigh-frequencyclockwhenthe OHFCbit is 0; it does not use the low-frequency clock when OLFC is 0.

During reset, the PC87591x clock does not toggle until OHFC is 1. During power mode change, if there is a request to switch

to a non-stable or non-toggling clock, the power mode change stalls.

4.17.4 The Power Management Controller Status Register (PMCSR)

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

PMCSR is a byte-wide, read/write register that selects the Active or Idle modes. In addition, it controls the operation of the

HFCG by enabling or disabling the high-frequency core clock domain. On reset, all non-reserved bits are cleared. PMCSR

format is shown below.

Location: 00 FF8016

Type: R/W

Bit 76543210

Name OLFC OHFC WBPSM Reserved IDLE DHF Reserved

Reset 00000000

Bit Description

0Reserved.

1DHF (Disable High-Frequency Oscillator). When cleared (0), the HFCG is enabled. In Active mode, the

HFCG is enabled regardless of the DHF value.

If in Idle mode, DHF can be used to reduce power consumption. When DHF=1, the HFCG is disabled and the

high-frequency clock is not generated. In Power off mode, the HFCG is disabled regardless of the DHF value.

DHF is cleared by the hardware when a hardware wake-up event is detected.

2IDLE. When set, the core domain enters Idle mode on the execution of a WAIT instruction. WBPSM must be

set before executing the WAIT instruction.

This bit can be set and cleared by software; it is cleared by hardware when a hardware wake-up event is detected.

4-3 Reserved.

5WBPSM (Wait Before Entering Power Save Mode). When set, the switch from Active to Idle mode is done by

setting the IDLE bit and executing a WAIT instruction. In addition, if DHF is set, the high-frequency oscillator is

disabled only after the WAIT instruction is executed and Idle mode is entered.

6OHFC (Oscillating High-Frequency Clock).

0: Indicates that the high-frequency clock received by the PMC is either disabled, not available or not producing

a stable clock. When OHFC is cleared, the PMC does not switch to Active mode.

1: Indicates that the high-frequency clock received by the PMC is available and producing a stable clock.

7OLFC (Oscillating Low-Frequency Clock).

0: Indicates that the low-frequency clock received by the PMC is either disabled, not available or not producing a

stable clock. When the OLFC is cleared, the PMC does not switch from Active mode to Power Save or Idle

modes.

1: Indicates that the low-frequency clock received by the PMC is available and producing a stable clock.

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4.17.5 Usage Hints

The hints below apply when Idle mode is used with a disabled HFCG.

1. When disabling HFCG in Idle mode, on wake-up, a frequency clock may be generated that differs from the selected set-

ting due to temperature variations in the working environment during the idle period. For details on the resulting deviation

from the nominal frequency, refer to “tCLKINTwk” on page 385. To avoid any failures that may result from waking up to

a higher frequency in case the access time to the internal or external memory is marginal using the current BIU config-

uration, follow the procedures exactly.

Before entering Idle mode, configure SZCFGi (where i=0-2) for an additional Wait clock cycle (see Section 4.1.10 on

page 83 for details on SZCFGi configuration).

2. After waking up from Idle mode, wait 0.5 seconds before returning to the optimal SZCFG0 configuration.

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4.18 HIGH-FREQUENCY CLOCK GENERATOR (HFCG)

The HFCG generates the high-frequency clock (OSCCLK) based on the system’s 32.768 KHz clock signal. The HFCG out-

put is derived from OSCCLK and generates the host domain clock and the core domain clock. Clock generation is controlled

by the core domain’s PMC module (see Section 4.17 on page 235) and the host domain’s SuperI/O configuration (see

Section 6 on page 335).

To generate OSCCLK, the HFCG includes a programmable frequency multiplier. The core domain clock is derived from

OSCCLK via a programmable pre-scaler; its frequency is in the range of 4 MHz to 20 MHz. The host domain clock is derived

from OSCCLK via a pre-scaler that divides by 2, generating an output of 48 MHz (see Figure 78).

4.18.1 Features

●Programmable frequency multiplier for a wide range of output frequencies

●Core domain clock and host domain clock generation

●Programmable pre-scaler to derive the core domain clock from OSCCLK

●Separate enable/disable for core domain clock and host domain clock

●On VCC power-up:

—4 MHz default core domain clock frequency is set

—Host domain clock is disabled

●On WATCHDOG reset and Debugger Interface reset:

—If host domain clock is enabled, the 48 MHz clock monitor is initiated

—If host domain clock is disabled, the 4 MHz default core domain clock frequency is set

4.18.2 Functional Description

Figure 78 shows the HFCG blocks.

The frequency multiplier includes a 5-bit variable (N) and a 14-bit variable (M); these variables define the OSCCLK frequen-

cy. There are two software methods to set the frequency of OSCCLK (by changing N and M); the method used depends on

the HFCG state, as described in Section 4.18.3. The methods are:

Software Method 1. Write new values (HFCGML, HFCGMH and HFCGN registers) to a buffer and enable the programma-

ble frequency setting. Either a normal or fast clock setting may be used. The programmable pre-scaler of the core domain

clock is automatically set to a divide by 1; see “PMC Enabled SuperI/O Disabled State” on page 240.

Frequency

Multiplier

N, M, I

32 KHz

Programmable

Control and Status Host Domain

Clock

Core Domain

Clock

Enable from PMC

Enable from SuperI/O

Pre-Scaler

Parameter Settings

Current Settings

Hardwired Settings

N, M, I for

= Includes software-accessible registers

OSCCLK

Divide by 2

Host Domain

INT to ICU

Figure 78. HFCG Schematic Diagram

= Software

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Software Method 2. Enable the hardwired frequency setting (M and N are set to generate a 96 MHz OSCCLK). Either a

normal or fast clock setting may be used. The programmable pre-scaler of the core domain clock is set according to the

HFCGP register; see “SuperI/O Enabled State” on page 242.

During a frequency change, the OSCCLK output is low to prevent the system from using an unstable clock.

The HFCG is designed to be tightly coupled with the PMC. The HFCG receives two enable signals: one from the PMC and

the other from the host domain. The PMC can enable or disable core domain clock generation while in Idle mode; it enables

the core domain clock in Active mode. The SuperI/O configuration enables or disables clock generation for the host domain

according to the host processor requests.

4.18.3 HFCG States

There are three groups of HFCG states:

●PMC Enabled SuperI/O Disabled: OSCCLK is programmable (set by hardware or by software method 1). The core

domain clock is enabled; the host domain clock is disabled.

●SuperI/O Enabled PMC Enabled/Disabled: OSCCLK is ﬁxed at 96 MHz (set by hardware or by software method 2).

The host domain clock is enabled; the core domain clock is either enabled or disabled depending on PMC.

●Disabled: OSCCLK is disabled. Both core domain clock and host domain clock are disabled.

Transitions between the states are controlled by either hardware or firmware. Figure 79 illustrates the states and the hard-

ware or software transitions between them. Some of the software settings and transitions are protected to improve the sys-

tem’s durability with regard to software errors; see details in the following sections.

PMC Enabled SuperI/O Disabled State

Normal Clock Setting. This operation enables changing the clock frequency while in PMC Enabled SuperI/O Disabled

state or switching from SuperI/O Enabled PMC Enabled state to PMC Enabled SuperI/O Disabled state.

To change the OSCCLK frequency, load the N and M variables with new values. M is loaded in two parts by writing to

HFCGML and HFCGMH registers.

Load the new setting (N and M values, simultaneously) into the frequency multiplier. The core writes the new variables into

a data input buffer. Then a command loads the new values into the frequency multiplier. The command also loads simulta-

neously the programmable pre-scaler with 0 (set to a divide by 1). Note that HFCGP register does not change its contents.

To set a new clock frequency:

1. Write the N value to HFCGN register.

2. Write the low byte of the M value to HFCGML register.

3. Write the upper bits of the M value to HFCGMH register.

4. Set LOAD in the HFCGCTRL1 register to 1.

SuperI/O Enabled

Disabled

PMC Enabled

SuperI/O Disabled

PMC Disabled PMC Enabled

PMC Enabled

PMC Disabled

PMCPMC

SuperI/O

Disabled

Enabled

Disabled

Load or Fast

Load96

Software Transitions

Hardware Transitions

Program Pre-Scaler

Reload M, N, I

or Fast96

May be done in response to

interrupt on SuperI/O Disabled

May be done in response to

interrupt on SuperI/O Enabled

Figure 79. HFCG States and Transitions

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When the new HFCGML, HFCGMH and HFCGN register values are loaded, the HFCG holds OSCCLK low until the frequen-

cy multiplier locks onto the target frequency and the new frequency stabilizes. The core domain clock is also low during this

time. This automatic locking process can take several milliseconds to complete.

Frequencies within the range of 4 MHz to 20 MHz are valid. See Table 36 for a sampling of selected frequencies and their

corresponding M and N values.

Table 36. Frequencies of Selected Settings

Fast Clock Setting. This operation enables changing the clock frequency while in PMC Enabled SuperI/O Disabled state

or switching from SuperI/O Enabled PMC Enabled state to PMC Enabled SuperI/O Disabled state.

The HFCG maintains an internal I variable. The I variable is defined by two byte-wide registers: HFCGIL and HFCGIH. If

new M and N values are loaded, the frequency multiplier automatically searches for the I value needed to lock onto the target

frequency. The locking process can take several milliseconds to complete. The I variable can be recorded for a given M and

N set of values and used later to reduce the time needed for frequency locking.

To record the I value:

1. Read the low byte of the I value via HFCGIL register.

2. Check if IVLID bit in HFCGCTRL1 register is set to 0. If yes, repeat steps 1 and 2.

3. Read the upper six bits of the I value via HFCGIH register.

To fast load a new setting, load the M and N values and the corresponding I value. Then set FAST bit in HFCGCTRL1 reg-

ister to 1. The FAST command loads (simultaneously) the new values into the frequency multiplier and loads the program-

mable pre-scaler with 0 (set to a divide by 1). Note that HFCGP register does not change its contents. The frequency

multiplier quickly locks onto the target frequency without searching for a new I value.

To fast set a new clock frequency:

1. Write the N value to HFCGN register.

2. Write the low byte of the M value to HFCGML register.

3. Write the upper bits of the M value to HFCGMH register.

4. Write the low byte of the I value to HFCGIL register.

5. Write the upper six bits of the I value to HFCGIH register.

6. Set FAST bit in HFCGCTRL1 register to 1.

Changes in temperature or voltage may cause variations in the value of I for a given output frequency. If these changes

occur in the interval between recording I and its use, the output frequency generated following a fast frequency setting may

differ from the target frequency. However, after some time, the output frequency converges to the desired frequency.

Frequency1(MHz)

1. This value is referred to as tCLKINTnom in the AC

speciﬁcations.

HFCGMH HFCGML HFCGN

4.00 (default) 0316 CF16 0816

5.00 0316 9216 0616

6.00 0316 9216 0516

7.00 0716 8116 0916

8.00 0A16 7C16 0B16

9.00 0A16 B916 0A16

10.00 0A16 B916 0916

12.00 1116 2A16 0C16

14.00 1916 0716 0F16

16.00 1116 2916 0916

18.00 1116 2916 0816

20.00 1716 D616 0A16

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SuperI/O Enabled State

Normal Clock Setting. This operation enables switching from PMC Enabled SuperI/O Disabled state to SuperI/O Enabled

PMC Enabled state.

To generate a 96 MHz OSCCLK, a command loads the hardwired M and N values (simultaneously) into the frequency mul-

tiplier. At the same time, the command loads the programmable pre-scaler with the value held in HFCGP register. To set a

96 MHz clock frequency and the required core clock.

1. Write the HFCGP value.

2. Set LOAD96 bit in HFCGCTRL1 register.

The HFCGN, HFCGML and HFCGMH registers are ignored and left unchanged when switching to SuperI/O Enabled states.

Fast Clock Setting. This operation enables fast switching from PMC Enabled SuperI/O Disabled state to SuperI/O Enabled

PMC Enabled state.

The HFCG maintains an internal I variable for the 96 MHz clock. The I variable is defined by two byte-wide registers: HFCGIL

and HFCGIH. In a LOAD96 operation, the frequency multiplier automatically searches for the I value needed to lock onto

the target frequency. The locking process can take several milliseconds to complete. The I variable can be recorded for the

96 MHz setting and used later to reduce the time needed for frequency locking.

To record the 96 MHz I value:

1. Write the required HFCGP value.

2. Enter any of the SuperI/O Enabled states using the Normal clock setting or Hardware clock setting process.

To fast set a 96 MHz clock frequency:

1. Write the required HFCGP value.

2. Set FAST96 bit in HFCGCTRL1 register to 1.

The HFCGN, HFCGML and HFCGMH registers are ignored and left unchanged when switching to SuperI/O Enabled states.

4.18.4 The Programmable Pre-Scaler: Core Domain Clock Generation

The core domain clock (CLK) is driven from OSCCLK via a 5-bit pre-scaler. When in PMC Enabled SuperI/O Disabled state,

the pre-scaler divides by 1. In SuperI/O Enabled PMC Disabled state, the pre-scaler is programmable, as defined in HFCGP

The core domain clock may be set in the range of 4 MHz to 20 MHz.

When LOAD96 or FAST96 bit in HFCGCTRL1 register is set (1), the pre-scaler is set to the value held in HFCGP register

(core frequency = 96 MHz / (HFCGP +1)).

When in SuperI/O Enabled PMC Enabled state, a write to HFCGP register changes the core’s frequency at the next cycle

of the pre-scaler.

When LOAD or FAST bit in HFCGCTRL1 register is set (1), the pre-scaler is automatically set to a divide by 1. The contents

of HFCGP are unchanged.

When in SuperI/O Enabled PMC Enabled state or SuperI/O Enabled PMC Disabled state, WATCHDOG reset or Debugger

Interface reset sets HFCGP to its reset value and initializes the pre-scaler using this value; see Section 4.18.6 on page 243

for details about setting the pre-scaler during state transitions.

When in Disabled state or PMC Enabled and SuperI/O Disabled state, WATCHDOG reset or Debugger Interface reset

keeps the pre-scaler in the divide by 1 operation and loads the HFCGP to its reset value.

In all states, on VCC power-up, WATCHDOG reset or Debugger Interface reset, HFCGP is set to its reset value and the pre-

scaler is set to a divide by 1.

4.18.5 State Transitions

The following section describes the actions taken by the HFCG during state transitions. Unless explicitly specified, the ac-

tions are initiated by hardware.

Transition to PMC Enabled SuperI/O Disabled State

●When transitioning from Disabled state:

—OSCCLK defaults to a frequency set by the input data buffer (according to the most recent LOAD, FAST or Reset

command).

—The pre-scaler defaults to a divide by 1.

●When transitioning from SuperI/O Enabled PMC Enabled state:

— Software sets OSCCLK and the pre-scaler by the LOAD or FAST command (software method 1).

●The host domain clock is disabled (low).

●The core domain clock is enabled and starts toggling as soon as the frequency multiplier has stabilized.

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When transitioning from SuperI/O Enabled PMC Enabled state, there may be a transition period in which the core domain

clock is still toggling according to the setting in SuperI/O Enabled PMC Enabled state. This occurs until software method 1

is performed by the interrupt handler of the SuperI/O Disabled event.

Transition to SuperI/O Enabled PMC Disabled State

●OSCCLK defaults to 96 MHz

●The host domain clock is enabled and starts toggling as soon as the frequency multiplier has stabilized

●The core domain clock is disabled (low)

Transition to SuperI/O Enabled PMC Enabled State

●When transitioning from SuperI/O Enabled PMC Disabled state:

—OSCCLK defaults to 96 MHz

—The pre-scaler is set according to HFCGP

●When transitioning from PMC Enabled SuperI/O Disabled state:

— Software sets OSCCLK and the pre-scaler by the LOAD96 or FAST96 command (software method 2)

●The host domain clock is enabled and starts toggling as soon as the frequency multiplier has stabilized

●The core domain clock is enabled and starts toggling as soon as the frequency multiplier has stabilized

When transitioning from PMC Enabled SuperI/O Disabled state, there may be a transition period in which the core domain

clock is still toggling according to the setting in PMC Enabled SuperI/O Disabled state. This occurs until software method 2

is performed by the interrupt handler of the SuperI/O Enabled event. During this transition period, the host domain clock is

still disabled.

4.18.6 48 MHz Clock Monitor

While in one of the SuperI/O Enabled states, a WATCHDOG reset or Debugger Interface reset does not interfere with the

operation of the SuperI/O. Thus, if the 48 MHz clock is correctly toggling, it is not interfered with. Toggling is monitored by

the 48 MHz clock monitor. If a violation is detected, the 48 MHz monitor error flag is set and the HFCG goes through a com-

plete reset, after which it is put into PMC Enabled SuperI/O Disabled state, ignoring the host domain enable signal.

The 48 MHz clock monitor is initiated when a WATCHDOG reset or Debugger Interface reset occurs while the HFCG is in

a SuperI/O Enabled state. The monitor checks that the host domain clock frequency is in the range of 48 MHz ±1%.

If the host domain clock frequency is in the correct range, the HFCG continues generating the 96 MHz OSCCLK, but the

programmable pre-scaler is set to a default of divide by 24. The HFCG is in SuperI/O Enabled PMC Enabled state.

The core reset routine is responsible for switching to SuperI/O Enabled PMC Enabled state and/or communicating the failure

to the host software.

4.18.7 HFCG Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

HFCG Register Map

Mnemonic Register Name Type

HFCGCTRL1 HFCG Control 1 Varies per bit

HFCGML M Low Byte Value R/W

HFCGMH M High Byte Value R/W

HFCGN N Value R/W

HFCGIL I Low Byte Value R/W

HFCGIH I High Byte Value R/W

HFCGP HFCG Pre-Scaler R/W

HFCGCTRL2 HFCG Control 2 Varies per bit

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HFCG Control Register 1 (HFCGCTRL1)

The HFCGCTRL1 register sets the frequency multiplier’s operating parameters. On VCC power-up, WATCHDOG reset and

Debugger Interface reset, it is initialized to 0C16.

Location: 00 FFA016

Type: Varies per bit

Bit 76543210

Name Reserved FAST96 LOAD96 IVLID OHFC PENABLE FAST LOAD

Reset 00001100

Bit Type Description

0WOLOAD (Load M and N Values). Write 1 to this bit to perform a normal frequency change by loading

the HFCGML, HFCGMH and HFCGN buffer data to the frequency multiplier. The pre-scaler is

automatically set to a divide by 1. The bit always reads back 0. Results are undefined when more than

one of the following bits is written with 1 at the same time: LOAD, FAST, LOAD96, FAST96.

1WOFAST (Load M, N and I Values). Write 1 to this bit to perform a fast frequency change by loading the

HFCGML, HFCGMH, HFCGN, HFCGIH and HFCGIL input buffer data in the frequency multiplier. The

pre-scaler is automatically set to a divide by 1. The bit always reads back 0. Results are undefined when

more than one of the following bits is written with 1 at the same time: LOAD, FAST, LOAD96, FAST96.

2ROPMC ENABLE (Enable Core Domain Clock). Provides the status of the PMC enable/disable

command. Any data written to this bit is ignored.

0: Disabled

1: Enabled

3ROOHFC (Output Clock Status). Indicates when the HFCG is oscillating and produces a stable clock.

Any data written to this bit is ignored.

0: Not oscillating

1: Oscillating with stable output

4ROIVLID (I Value Valid).

0: Data read is invalid; repeat HFCGIL register read operation

1: Data read is valid; HFCGIH can be read

5WOLOAD96 (Load M and N Values for 96 MHz). Write 1 to this bit to perform normal locking on 96 MHz

frequency by loading the hardwired variables M and N to the frequency multiplier. The pre-scaler is set

according to the value held in HFCGP register. The bit always reads back 0. Results are undefined

when more than one of the following bits is written with 1 at the same time: LOAD, FAST, LOAD96,

FAST96.

6WOFAST96 (Load M, N and I Values for 96 MHz). Write 1 to this bit to perform fast locking on 96 MHz

frequency by loading the hardwired variables M and N and registers HFCGIH and HFCGIL to the

frequency multiplier. The pre-scaler is set according to the value held in HFCGP register. The bit

always reads back 0. Results are undefined results when more than one of the following bits is written

with 1 at the same time: LOAD, FAST, LOAD96, FAST96.

7Reserved.

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HFCGM Low Value Register (HFCGML)

The HFCGML register contains the lower eight bits of the frequency multiplier M value. Data written to the register is stored

in the setup buffer. Reading the register returns the HFCGML value of the currently set frequency. On VCC power-up,

WATCHDOG reset and Debugger Interface reset, it is loaded with CF16.

Location: 00 FFA216

Type: R/W

HFCGM High Value Register (HFCGMH)

The HFCGMH register contains the upper bits of the frequency multiplier M value. Data written to the register is stored in

the setup buffer. Reading the register returns the HFCGMH value of the currently set frequency. On VCC power-up, WATCH-

DOG reset and Debugger Interface reset, it is loaded with 0316.

Location: 00 FFA416

Type: R/W

HFCGN Value Register (HFCGN)

The HFCGN register is a byte-wide, read/write register containing five bits of the frequency multiplier N value. Data written to the

register is stored in the setup buffer. Reading the register returns the HFCGN value of the currently set frequency. On VCC

power-up, WATCHDOG reset and Debugger Interface reset, it is loaded with 0816.

Location: 00 FFA616

Type: R/W

Bit 76543210

Name HFCGM7-0

Reset 11001111

Bit Description

7-0 HFCGM7-0. Contains the lower eight bits of the M value.

Bit 76543210

Name HFCGM

Reset 00000011

Bit Description

7-0 HFCGM. Contains the upper bits of the M value.

Bit 76543210

Name Reserved HFCGN4-0

Reset 00001000

Bit Description

4-0 HFCGN4-0. Contains the five bits of the N value.

7-5 Reserved.

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HFCGI Low Value Register (HFCGIL)

The HFCGIL register contains the lower eight bits of the frequency multiplier I value. Data written to the register is stored in

the setup buffer. Reading the register returns the value of its first 8 bits. (IVLID bit in HFCGCTRL1 register indicates if the

data is valid.)

Location: 00 FFA816

Type: R/W

HFCGI High Value Register (HFCGIH)

The HFCGIH register is a byte-wide, read/write register containing the upper six bits of the frequency multiplier I value. Data

written to the register is stored in the setup buffer. Reading the register returns the HFCGIH value of the currently set fre-

quency.

Location: 00 FFAA16

Type: R/W

HFCG Pre-Scaler Register (HFCGP)

The HFCGP register is a byte-wide, read/write register. It allows the core clock to be derived from the 96 MHz clock.

On reset HFCGP is initialized to 1716.

Location: 00 FFAC16

Type: R/W

Bit 76543210

Name HFCGI7-0

Bit Description

7-0 HFCGI7-0. Contains the lower eight bits of the I value.

Bit 76543210

Name Reserved HFCGI13-8

Bit Description

5-0 HFCGI13-8. Contains the upper six bits of the I value.

7-6 Reserved.

Bit 76543210

Name Reserved HFCGP4-0

Reset 00010111

Bit Description

4-0 HFCGP4-0 (Pre-Scaler Divider Value). The divider of OSCCLK is the number defined by HFCGP(4-0) + 1,

e.g., a value of 0016 results in a divide by 1; a value of 1F16 results in a divide by 32.

Results are undeﬁned when the pre-scaler holds a value that yields a core domain clock frequency higher than

20 MHz or lower than 3 MHz.

The pre-scaler is set according to the value held in HFCGP register when LOAD96 bit or FAST96 bit is set (1).

Reading HFCGP register returns the last value written to it.

7-5 Reserved.

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HFCG Control Register 2 (HFCGCTRL2)

The HFCGCTRL2 register sets the frequency multiplier’s operating parameters. On VCC power-up, WATCHDOG reset and

Debugger Interface reset, it is initialized to 0016.

Location: 00 FFAE16

Type: Varies per bit

Bit 76543210

Name Reserved 96MON MONERR SCESTP SCESTR SENABLE

Reset 00000000

Bit Type Description

0ROSIO ENABLE (Enable Host Domain Clock). Provides the status of the SuperI/O enable/disable

command. Any data written to this bit is ignored.

0: Disabled

1: Enabled

1 R/W1C SCESTR (SIO Clock Enable Start). Indicates that a rising edge was detected on the SENABEL

signal. When set, an interrupt is sent to the ICU (level high). Cleared by writing 1 to it. This interrupt

may be masked only in the ICU.

0: No rising edge on SENABLE was detected (default)

1: A rising edge on SENABLE was detected and an interrupt is sent to the ICU

2 R/W1C SCESTP (SIO Clock Enable Stop). Indicates that a falling edge was detected on the SENABEL

signal. When set, an interrupt is sent to the ICU (level high). Cleared by writing 1 to it. This interrupt

may be masked only in the ICU.

0: No falling edge on SENABLE was detected (default)

1: A falling edge on SENABLE was detected and an interrupt is sent to the ICU

3 R/W1C MONERR (Monitor Error). Indicates that a 48 MHz monitor error was detected during the last

WATCHDOG or Debugger Reset process. Note that this bit is cleared by all resets except WATCHDOG

and Debugger Interface resets. Once set, this bit is cleared by writing 1 to it.

0: No error detected (default)

1: 48 MHz monitor detected an out of range frequency

4RO96MON (96 MHz Oscillations On). Indicates the oscillation frequency at which the HFCG is operating.

0: HFCG is oscillating as defined by the HFCGM and HFCGN. The core clock is identical to HFCG fre-

quency.

1: HFCG is oscillating at 96 MHz. The core clock is pre-scaled as defined by HFCGP.

7-5 Reserved.

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4.19 THE DEBUGGER INTERFACE

The Debugger Interface module links between a debugger running on a host machine and the PC87591x.

The Debugger interface associates a processor number with the processor core. The number associated with the core is 0.

The Debugger interface can also program the on-chip flash.

4.19.1 Features

●Debugger communication via an IEEE 1149.1b 1994 JTAG serial bus

●Test Access Port (TAP) for JTAG serial bus

●Hardware reset signal assertion by debugger command

●Conﬁgurable ABORT event

●Interrupt signal (TINT) to the debugger indicates a waiting message

●Waiting message to on-chip processor by non-maskable ISE interrupt

●8-word (16-byte) Rx (downstream) data link

●8-word (16-byte) Tx (upstream) data link

●On-chip ﬂash support

—Read, Program and Erase

—Read protect option to secure contents

4.19.2 Structure

The Debugger interface consists of a TAP, ISE Interrupt Control, Rx and Tx data links and a PC87591x reset-by-command

source circuit. Figure 80 shows these functional blocks.

Figure 80. Debugger Interface

Rx Data

Peripheral Bus

Tx Data

ISE Interrupt

Control

TAP

JTAG Serial Bus TINT

ISE

Interrupts

Debugger

Reset

Link Link

Flash Programing

Interface

Flash

On-Chip To

Reset Circuit

and Flash

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The TAP block has an IEEE 1149.1b 1994 standard interface to a JTAG serial bus. In addition, it uses TINT to notify the

host/debugger that a message is waiting upstream. The TAP and the JTAG form the debugging communication channel and

port for the PC87591x. They operate as follows:

●The TAP copies downstream messages (from the debugger to one of the on-chip processors) to the Rx data link, to

be read by the relevant processor via the peripheral bus.

●A processor writes upstream messages (from an on-chip processor to its debugger) to the Tx data link for upstream

transmission via the JTAG serial bus.

●The ISE interrupt control generates ISE interrupts to the processor in cases of ABORT or a waiting message in the

Rx data link.

●The debugger reset circuit generates a PC87591x reset by a debugger command. This is in addition to the Power-Up

and Hardware reset sources.

●Flash access (control, status, read, write and erase) interface and control is provided. The Debugger interface gen-

erates a reset signal when JTAG access to the ﬂash is enabled.

4.19.3 Debugger Interface Functional Description

The Debugger interface supports four operating modes: Rx session, Tx session, chip RESET and ABORT. Some of these

modes can be active simultaneously for the same or different processors. The ISE interrupt control block includes hooks to

control these conditions.

Rx Session (Sending Data Downstream)

A message sent downstream by the debugger to a processor is called an Rx session. In an Rx session, a debugger uses

both the TAP and the JTAG to monitor the “busy” indication for the Rx data link. Following a “not busy” indication, a message

is sent to a processor via the JTAG, TAP and Rx data link.

One of the internal ISE interrupts is asserted (if not active) according to the PID field of the instruction currently loaded into

the TAP IR register. The signaled processor accesses the data link via the peripheral bus, reads the message length (op-

tional) and fetches it from the Rx data buffer.

At the end of the data transfer, the processor turns off the “busy” indication of the Rx data link.

Tx Session (Sending Data Upstream)

A message sent upstream by a processor to the debugger is called a Tx session. In a Tx session, one of the processors

tries to own the Tx data link by accessing the Tx semaphore DBGTXLOC register. If successful, it writes a message body

to the Tx data buffer and a message length, in words, to DBGTXST register.

After completion of the data buffer update, the processor sets ASSERT bit in DBGTINT register to 1. This signals the de-

bugger with an active-low pulse on TINT. The debugger reads the data using both the TAP and the JTAG.

At the end of the data transfer, the semaphore circuit is set to “not busy” and TINT is released.

Chip RESET

The PC87591x is reset by a dedicated TAP instruction.

ABORT

Either a TAP instruction or a bit-set operation in DBGABORT register generates an ABORT. Asserting an ISE interrupt to-

gether with a non-zero ABORT_i bit in DBGISESRC register signals an ABORT operation. The ISE interrupt control circuit

asserts the ISE interrupt according to the pre-programed mask bits in ABORT_MASK register. A dedicated circuit, together

with a set of registers in the ISE Interrupt Control, clears the ISE requests after they have been served.

Rx Data Link

The Rx data link consists of an 8-word read/write data buffer, DBGRXD0 to DBGRXD7 registers and the Status (DBGRXST)

On PC87591x reset, DBGRXST register is set to its reset value. On TAP reset, the data link maintains its values.

When the TAP controller is in Update-DR state and the current IR is SCAN_RX, DBGRXDX registers are updated from the

TAP Data Shift (DBGDATA) register. Data is valid to the processor only while BUSY bit in DBGRXST register is set. In this

case (i.e., Update-DR of SCAN_RX), the TAP controller copies the PID and length fields from its IR to the Status register

and sets BUSY bit to 1 in this state.

A processor may turn off the BUSY bit by writing 1 to it. BUSY can be cleared even when TCK is not toggling. The Rx data

link functions in Active or Idle modes.

DBGDATA length is set to the length field of the SCAN_RX instruction before Capture_DR state (see Section 4.19.7 on

page 260). No parallel load is executed in Capture-DR state.

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TX Data Link

The Tx Data link consists of an 8-word, read/write data buffer, DBGTXD0 to DBGTXD7 registers, a read/write Status register

(DBGTXST), a read/write semaphore lock register (DBGTXLOC) and a write-only TINT control register (DBGTINT).

On Power-Up reset, the Tx Data link is reset (negating any pending message), DBGTXLOC and DBGTXST are set to their

reset values and TINT is released (1). On Warm and Internal reset, any partial message (i.e., TINT=1) is negated by setting

DBGTXLOC and DBGTXST to their reset values. Messages that were completed (i.e., TINT=0) are maintained for transmis-

sion to the host by maintaining DBGTXLOC and DBGTXST values.

On TAP reset, the data link maintain its values.

DBGTXD registers are captured by the TAP data shift register (DBGDATA) in Capture-DR state of the TAP controller when

the current Information Register (IR) is SCAN_TX. The DBGDATA length is set dynamically, according to the length field of

DBGTXST register before the Capture_DR state of the SCAN_TX operation (see Section 4.19.7 on page 260). The TAP IR

state. No parallel load is executed in Update-DR state.

The semaphore is implemented by DBGTXLOC register. A write operation, to PID field of this register, of a value other than

‘1111’ changes the contents of this field only when the PID field equals ‘1111’. This field returns to ‘1111’ in one of the fol-

lowing ways:

●Write operation of ‘1111’ to PID ﬁeld of DBGTXLOC register from the peripheral bus while TINT is not asserted

●Update-DR state of the TAP controller when the current instruction loaded into TAP IR register is SCAN_TX (this ac-

tion take place at the rising edge of TCK)

●On Warm or Internal reset if TINT=1 and on Power-Up reset

A processor can access DBGTXDi registers in Active mode only. For a processor to gain ownership of the Tx link, it must

capture the DBGTXLOC semaphore using the following sequence:

1. Verify that the value of PID in DBGTXLOC register is ‘1111’.

2. Write the processor PID code to DBGTXLOC register.

3. Read DBGTXLOC. If the PID field is equal to the value that was written, the data link is granted. If not, repeat step 1.

A processor should access DBGTXDi and DBGTXST registers only after successfully gaining ownership over the Tx link by

using the above sequence.

The TINT signal is an active-low pulse asserted by the Tx data link when ASSERT bit in DBGTINT register is written with 1.

It is de-asserted, together with the semaphore indication in Update-DR state of the TAP controller, when the current instruc-

tion loaded into TAP IR register is SCAN_TX.

Access to DBGTXLOC, DBGTXST and DBGTXDi registers should be done only while TINT is not asserted. TINT negation

can be identified by the release of PID (‘1111’).

Debugger Reset Circuit

Chip reset is asserted in the Update-DR state of the TAP controller when the current instruction is ASSERT_DBG_RST. This

triggers a Debugger reset, as described in “ASSERT_DBG_RST” on page 260. This circuit is functional in Active or Idle

modes. It is functional, while TCK is not toggling, one cycle after exit from Update-DR state.

ISE Interrupt Control

The ISE interrupt control module sends ISE interrupt requests to the processor core. It consists of the write-only DBGABORT

The DBGISESRC register is cleared on PC87591x reset. During TAP reset, the values of these registers are maintained.

The DBGMASKS value is modified only in Update-DR state of the TAP controller when the current instruction is

SCAN_ABORT_MASK.

The ISE interrupt control module issues an ISE interrupt request to a specific processor or multiple processors, together with

the matched bit in DBGISESRC register, according to the MESSAGE or ABORT event.

In a MESSAGE event, an ISE interrupt is requested for a specific processor according to the PID field of the SCAN_RX

instruction. The request is issued (together with DBGISESRC bit assertion) if the current instruction loaded in TAP IR is

SCAN_RX and the TAP controller is in Update-DR state (rising edge of TCK).

An ABORT event occurs when SCAN_RX is executed with a PID of all 1s (ISE and ABORT_i bits in DBGISESRC register

are asserted) or when processor bits P_i are set in DBGABORT register by one of the processors. That is, ISE and

DBGISESRC bits are asserted with the write operation itself; if DBGABORT is written with some 0 bits, the PIDs related to

these bits do not get the ISE. In an ABORT event, the assertion of each ISE interrupt and DBGISESRC bit depends on its

masking bit in DBGMASKS register.

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Each ISE interrupt is cleared when ABORT_i and RX_i in DBGISESRC register are both 0. Any bit in DBGISESRC register

is cleared by writing 1 to it (writing 0 is ignored). If there is a new source activity in the same write cycle during which

DBGISESRC register of a specific processor is cleared, the ISE interrupt control asserts ISE again, together with its source

bit.

The ISE interrupt is an active-high pulse. For nested ISE sources, the ISE remains asserted, and the ISE interrupt control

module sets the new source bit to 1.

The DBGMASKS register is not available to the peripheral bus; it is accessed only from the JTAG serial bus when the

SCAN_ABORT_MASK instruction is loaded into the TAP IR.

The ISE signal, together with its source bit, should be asserted in Active or Idle modes for wake-up purposes when the

source is a debugger message or debugger abort. Other functionality should be consistent while changing modes (i.e., dur-

ing wake-up). Full functionality of this module is maintained even when TCK is not toggling.

Clock Synchronization

Some operations are related to TCK, others to the PC87591x main clock and yet others are asynchronous. The PC87591x

logic guarantees correct operation and a meta-stable protected interface in all its operating modes (i.e., Active and Idle).

The core may access the Debugger interface registers only in Active mode.

4.19.4 Flash Interface Functional Description

The Flash interface enables access to the flash through the JTAG serial bus without any core involvement. This enables a

firmware-independent update of flash contents.

The Flash interface is divided into three parts:

●Flash Control and Status: Controls ﬂash operations and returns ﬂash status.

●Flash Address: Stores the address for ﬂash operations and includes an auto-increment mechanism for speeding up

the ﬂash update process.

●Flash Data: Handles ﬂash data for both read and write operations.

Enabling Access to the Flash

The flash can be accessed through the JTAG serial bus in OBD and DEV environments. In IRE and PROG environments,

access cannot be enabled (i.e., write operations to the JTAG Access Enable (JTFIE) bit in the Flash Control and Status reg-

ister, FL_CT_ST, are ignored).

To enable Flash interface access to the flash, use the following sequence:

1. Set Instruction Register (IR) to Flash Control Scan Instruction.

2. Scan in a code with the Flash JTFIE bit in FL_CT_ST register is set to enable access to the PC87591x.

3. Repeat step 2 until the FMBUSY bit in FL_CT_ST register is cleared.

Enabling the flash puts the PC87591x in Reset state. It remains in this state, with the clocks enabled and any core or host

activity disabled, until the Flash interface is again disabled. To disable the flash, clear the JTFIE bit. This releases the

PC87591x from reset and enables the core to start executing the code stored in the flash.

Flash Contents Protection

The flash has a contents protection mechanism that protects the flash contents from read operations and prevents them

from being altered during write transactions. When this mechanism is set, only a special erase that erases the entire flash

can be performed.

When the Blank Flash flag is set, it indicates to the core that the flash has no valid code and that the core should remain in

Reset state until the protection information is changed. Both this flag and the Access Enable flag are part of the flash pro-

tection byte and should be programed after the flash is loaded with data. See Section 4.16.6 on page 226.

Flash Data Read

To read the contents of the flash, perform the following sequence:

1. Enable flash access (if not already enabled).

2. Set the flash to read as follows:

a. Set the IR to Flash Control and Status Scan instruction.

b. Scan in a read operation code (800016).

3. Set the address as follows:

a. Set IR to Flash Address Scan instruction.

b. Scan the address of the memory location to be read into the chip.

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4. Read the data as follows:

a. Set IR to Flash Data Read Scan instruction.

b. Scan out of the chip the first word of the data.

c. Repeat step b for additional data words for consecutive addresses.

Flash Data Erase

Pages, sections or the entire flash device (special erase) can be erased. If the flash is locked (FLAEN in the Flash Status

To select and perform a flash erase, perform the following sequence:

1. Enable flash access (if not already enabled).

2. Set the desired erase mode as follows:

a. Set IR to Flash Control and Status Scan instruction.

b. Scan in a code of 810016 (page erase), 820016 (section erase) or 840016 (special erase).

3. Set the address as follows:

a. Set IR to Flash Address Scan instruction.

b. Scan an address into the memory block to be erased, specifying the correct block.

4. Erase the page or section as follows:

a. Set IR to Flash Data Erase Scan instruction.

b. Scan the erase command into the chip with 116 data.

c. Repeat the scan with 016 data until the Busy status flag indicates erase completion. The Error bit indicates if the erase

was successful. In case of an error, the failing address is provided in Flash Address register.

d. To erase additional pages or sections, repeat the Set Address (3) and Erase (4) operations.

5. Erase the entire flash device (special erase) as follows:

a. Set IR to Flash Data Erase Scan instruction.

b. Scan the erase command into the chip with 116 data.

c. Repeat the scan with 016 data until the Busy status flag indicates erase completion. The Error bit indicates if the erase

was successful. In case of an error, the failing address is provided in Flash Address register.

d. If there is no error indication, repeat steps b and c two more times.

Flash Data Write

Writing data to the flash should be done after properly erasing the page (see “Flash Page Organization and Erase Options”

on page 221 for flash write after erase limitations).

To write data, perform the following sequence:

1. Enable flash access (if not already enabled).

2. Set the flash to Program mode as follows:

a. Set IR to Flash Control and Status Scan instruction.

b. Scan in a code of 808016 for program enable.

3. Set the address as follows:

a. Set IR to Flash Address Scan instruction.

b. Scan an address into the memory address to be written.

4. Write the block as follows:

a. Set IR to Flash Data Write Scan instruction.

b. Scan the write data into the chip with the data byte/word and Valid bit set.

c. Repeat the scan instruction as long as the Valid bit is cleared, checking for the returned Valid status flag to indicate

a ‘not busy’ status. The Error bit indicates if an error occurred during the write process of the previous word. On suc-

cessful write completion, the address is incremented to the next address. In case of an error, the failing address is

provided in Flash Address register; further writes are disabled until the error flag is cleared. The exact source of the

error is provided in FL_CT_ST register. The error may be cleared using FL_CT_ST register.

5. Repeat the write operation (step 4) for writing data to successive addresses.

6. Check that the write is completed by reading the Flash Status bit until it indicates that the flash is not busy; to do this:

a. Set IR to Flash Control and Status Scan instruction.

b. Scan in a code of 808016, maintaining the program enable.

c. Check the capture status for completion of the last write (the FMBUSY bit should be cleared).

d. Repeat steps b and c until the flash is not busy.

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Flash ID Read

To identify the device version, perform the following sequence:

1. Enable flash access (if not already enabled).

2. Read the Device ID (SID and SRID register values), using the Device ID Scan, as follows:

a. Set the IR to Device ID Scan instruction.

b. Scan the LF_ID chain.

4.19.5 Test Access Port (TAP)

This section defines the top-level design of the TAP, as illustrated in Figure 81. Subsequent sections provide detailed TAP

design requirements.

The TAP includes the following elements:

●TAP signals

●TAP controller

●Instruction Register (IR)

●Data registers (Debugger and Flash interfaces).

The Instruction and data registers have separate shift register-based paths connected in parallel. These registers have a

common serial data input and a common serial data output connected to the TAP TDI and TDO signals, respectively.

The TAP controller selects between TDI and TDO as the alternative instruction and data register paths.

Figure 81. TAP Block Diagram

DBGDATA Register

Instruction Register

Instruction Decode

Output Buffer

TDI TDO

Clocks and/or Controls

TAP Controller

TMS

TCK

DBGMASKS Register

BYPASS Register G

FL_ADDR Register

FL_DATA Register

FL_ID Register

FL_CT_ST Register

FL_ERASE Register

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Further Information

The TAP is based on the test logic in the IEEE 1149.1b-1994 specification. However, since its purpose is to facilitate com-

munication, it does not support IEEE 1149.1b-1194 testing facilities. It is used here to benefit from off-the-shelf bus controller

cards and software and potential future enhancements to the test scheme.

This document includes the relevant rules of this specification. See the following documents for further information.

●For further details and examples of the standard, see IEEE Standard Test Access Port and Boundary-Scan Architec-

ture, May 21, 1990.

●For further details of test bus chips and equipment, see the relevant manufacturer datasheets and application notes,

e.g., SCANTM Data book, National Semiconductor 400102.

●For technical background, refer to text books on the subject, for example, Colin M. Maunder and Rodham E. Tulloss,

“The Test Access Port and Boundary-Scan Architecture”, IEEE Computer Society Press Tutorial.

TAP Signals

The TAP interface signals to the JTAG serial bus are: Test Clock Input (TCK), Test Mode Select Input (TMS), Test Data Input

(TDI) and Test Data Output (TDO). The TAP controller is reset at Power-Up reset only; see Section 3.2 on page 65 for further

information.

TCK. TCK provides the clock for the JTAG serial bus and the TAP controller. Stored-state devices in the TAP maintain their

state indefinitely after the signal applied to TCK is stopped.

TMS. The TAP controller next state is set by the TMS value and its current state. The TAP samples the signal presented at

TMS on the rising edge of TCK.

Circuitry, fed from TMS, produces the same response to the application of a logic 1 as for a non-driven input.

TDI. This is the data and instructions serial input. The TAP samples the signal presented at TDI on the rising edge of TCK.

Circuitry fed from TDI produces the same response to the application of a logic 1 as for a non-driven input.

When data is shifted from TDI towards TDO, test data received at TDI appears without inversion at TDO following a number

of rising and falling edges of TCK. This is determined by the length of the instruction or Test Data register selected.

TDO. This is the data and instructions serial output. The signal driven through TDO changes its state only after the falling

edge of TCK.

The TDO driver is set to its inactive drive state, except while data or an instruction is being scanned.

TAP Controller

The TAP controller is a synchronous, finite state machine that responds to changes in the TMS and TCK signals and controls

the sequence of operations of the PC87591x reset, ISE interrupt control and data link circuitry.

Figure 82 shows the TAP controller state diagram.

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Figure 82. TAP Controller State Diagram

For a detailed description of the controller states, see the IEEE 1149.1b-1994 specifications.

All state transitions of the TAP controller occur based on the value of TMS on the rising edge of TCK. TAP actions (described

in Sections 2.1.3 to 2.1.7) occur either on the rising or falling edge of TCK in each controller state, as shown in Figure 83.

Figure 83. Timing of Actions in a Controller State

Tap-Reset

Run-Test

Idle Select-

DR-Scan

Capture-DR

Shift-DR

Exit1-DR

Pause-DR

Exit2-DR

Update-DR

01Select-

IR-Scan

Capture-IR

Shift-IR

Exit1-IR

Pause-IR

Exit2-IR

Update-IR

0101

Note: The value for each state transition represents the signal on TMS

for a rising edge at TCK.

State Entered

Controller State

TCK

Actions Occurring on the

Falling Edge of TCK

Actions Occurring on

Rising Edge of TCK

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TAP Controller Operation

The TAP controller changes state only in response to the following events:

●A rising edge of TCK

●Power-up

The TAP controller generates signals to control the operation of the TAP registers and associated PC87591x reset, ISE in-

terrupt control and data link circuitry.

The TDO output buffer and the circuitry that selects the register output fed to TDO are controlled as shown in Table 37.

Changes at TDO, as defined in Table 37, occur on the falling edge of TCK after entry into the state.

Table 37. TAP Operation in Each Controller State

TAP Controller Initialization

Circuitry built into the PC87591x forces the TAP controller into TAP-Reset state at power-up in an asynchronous manner.

The TAP controller must not be initialized by operation of any system input, such as a system reset.

When TMS is equal to 1 for five consecutive TCK cycles, this forces the controller into TAP-Reset state from any state.

4.19.6 TAP Instruction Register

The Instruction Register (IR) allows an instruction to be shifted into the Debugger interface. The instruction selects the mode

of operation, the data register to be addressed or both.

In any serial scan operation, the JTAG serial bus controller transmits and receive vectors of the same length. This serial

scan chain property is used to transmit status bits from the device to the bus controller in any instruction scan operation. The

Instruction register in the PC87591x allows status information generated within the data links to be examined and supports

flash programing, as shown in Table 38 on page 257.

Design and Construction

The IR uses a shift register-based design with a parallel input for register cells other than the two nearest to the serial output.

An instruction, shifted into the register, is latched at the completion of the shifting process.

The IR includes 12 shift register-based cells capable of holding instruction data.

An instruction that is shifted into the register is latched so that the related changes occur only in the Update IR and TAP-

Reset states.

Controller State Register Selected to Drive TDO TDO Driver Level

Tap-Reset Undeﬁned Inactive

Run-Test-Idle Undeﬁned Inactive

Select-DR-Scan Undeﬁned Inactive

Select-IR-Scan Undeﬁned Inactive

Capture-IR Undeﬁned Inactive

Shift-IR Instruction Active

Exit1-IR Undeﬁned Inactive

Pause-IR Undeﬁned Inactive

Exit2-IR Undeﬁned Inactive

Update-IR Undeﬁned Inactive

Capture-DR Undeﬁned Inactive

Shift-DR Test Data Active

Exit-DR Undeﬁned Inactive

Pause-DR Undeﬁned Inactive

Exit2-DR Undeﬁned Inactive

Update-DR Undeﬁned Inactive

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Data is not inverted between the serial input and serial output of IR.

The IR parallel input status bits, loaded at the Capture IR state of any instruction scan operation, are shown below.

Instruction Register Operation

Table 38 shows the behavior of IR in each TAP controller state.

All actions resulting from an instruction terminate when a new instruction is transferred to the parallel output of the IR (i.e.,

in Update-IR or TAP-Reset states).

All operations of the shift register stages occur on the rising edge of TCK after entry into a TAP controller state.

Table 38. Instruction Register Operation in Each Controller State

The data present at the parallel output of the IR is latched from the shift register stage on the falling edge of TCK in Update-

IR state.

After entry into TAP-Reset state as a result of TAP controller clocked operation, the BYPASS instruction is latched onto the

IR output on the falling edge of TCK.

Bit 1176553210

Name MSG_LEN PID RX_BUSY 0 1

Reset

Bit Description

0 Fixed value (1).

1 Fixed value (0).

2RX_BUSY (Receive Busy). Busy indication from the Rx data link.

6-3 PID (Processor ID). Contains the processor ID from the Tx data link.

When TINT is set to 1 (not active), PID ﬁeld is ‘1111’, indicating that the Tx link has no valid data.

When TINT is set to 0 (active), PID ﬁeld indicates the value of PID ﬁeld in DBGTXLOC register. Note that this

value is latched when TINT becomes active and is held until the Rx data is read by the host.

11-7 MSG_LEN (Message Length). Contains the Tx message length in words. When the Tx status word PID ﬁeld is

not ‘1111’, the MSG_LEN holds a copy of the MSG_LEN ﬁeld in DBGTXST register. When the size of this ﬁeld

is less than ﬁve bits, the MSG_LEN MSBs in the status word are forced to 0.

Controller State Shift Register Stage Parallel Output

TAP-Reset Undeﬁned Set to give BYPASS instruction

Capture-IR Load status data (table 2-2) Retain last state

Shift-IR Shift towards serial output Retain last state

Exit1-IR

Exit2-IR

Pause-IR

Retain last state Retain last state

Update-IR Retain last state Load from shift register stage

All other states Undeﬁned Retain last state

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Instructions

Instructions are entered serially into the Debugger interface logic during an IR scan by using the IR. See Table 39 for the

required binary codes.

Table 39. IR Instruction Binary Codes

Note:

●1. D0 is the nearest to the serial output.

●2. “X” means ignore.

●3. Debugger abort is generated by SCAN_RX when PID=‘1111’.

Data registers not selected by the current instruction do not interfere with the operation of the on-chip system logic or with

the selected data registers.

Each instruction enables a single serial data register path to shift data between TDI and TDO in Shift-DR state, as shown in

Table 40.

Instruction codes that are not required to control test logic are equivalent to the BYPASS instruction.

BYPASS

The BYPASS instruction operates the BYPASS register. This register contains a single shift register stage and provides a min-

imum-length serial path between the TDI and TDO pins of a component when no test operation is needed for that component.

This allows more rapid movement of test data to and from other board components that are required to perform test operations.

The BYPASS instruction selects BYPASS register to be connected for serial access between TDI and TDO in the Shift_DR state.

If the BYPASS instruction is selected, all other data registers continue their normal functionality.

Flash Support Instructions

Flash Control Scan

The Flash Control Scan instruction switches the data scan path to FL_CT_ST register. During this instruction, the length of

the scan chain is 16 bits. In this case, the Control and Status register of the flash can be scanned. In the Capture-DR state

of the TAP controller, the Status register is latched into the FL_CT_ST register chain. During the Update-DR state, the Con-

trol register is loaded with the contents of FL_CT_ST register. Some bits are shared between the two registers and operate

as read/write or read/write 1 to clear.

Device I/D Scan

The Device I/D Scan instruction switches the data scan path to FL_ID register. During this instruction, the length of the scan

chain is 32 bits. In this case, SID and REVID registers of the SuperI/O are read and their contents are sampled in the

Capture-DR state. No updates are made during the Update-DR state.

Flash Address Scan

The Flash Address Scan instruction switches the data scan path to FL_ADDR register. During this instruction, the length of

the scan chain is 32 bits. In this case, the Address register of the flash can be scanned. In the Capture-DR state of the TAP

controller, the flash address is latched into the FL_ADDR chain. During the Update-DR state, if the Block ID field is other

than ‘0000’, Flash Address register is loaded with a new value from FL_ADDA and the Valid bit in the data register is cleared.

After Flash Address register is loaded, a read operation from the array is performed, the result is stored in the Flash Read

Data buffer, and the Data Read buffer Valid bit is set.

D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Instruction

x x x x x x x x x 1 1 1 BYPASS

x x x x x x x x x 0 0 0 BYPASS (Reserved for Scan)

x x x x x x x x x 1 1 0 BYPASS

0 0 0 0 0 0 0 0 0 0 0 1 Flash Control Scan

0 0 0 0 0 0 0 0 1 0 0 1 Device I/D Scan

0 0 0 0 0 0 0 1 0 0 0 1 Flash Address Scan

0 0 0 0 0 0 1 1 0 0 0 1 Flash Data Read Scan

0 0 0 0 0 1 0 1 0 0 0 1 Flash Data Write Scan

0 0 0 0 0 1 1 1 0 0 0 1 Flash Erase Scan

other 0 0 1 BYPASS

L4 L3 L2 L1 L0 PID3 PID2 PID1 PID0 0 1 0 SCAN_RX

x x x x x x x x x 0 1 1 SCAN_TX

x x x x x x x x x 1 0 1 SCAN_ABORT_MASK

x x x x x x x x x 1 0 0 ASSERT_DBG_RST

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Flash Data Read Scan

The Flash Data Read Scan instruction switches the data scan path to FL_DATA register. During this instruction, the length

of the scan chain is 18 bits. In the Capture-DR state, the Flash Read Data buffer and the two status bits are loaded into the

shift register and the Valid bit is cleared. The Error bit indicates any error that occurred during the read operation.

If the Valid bit read was cleared, the data and error fields should be ignored. If the Valid bit read was set, the address is

incremented after the Capture-DR state. A data read from the memory is performed, placing the data in the Flash Read Data

buffer and setting the Valid bit.

When the flash address is in the flash main block or Information block, the data read is one word and the address increment

is two.

Flash Data Write Scan

The Flash Data Write Scan instruction switches the data scan path to FL_DATA register. During this instruction, the length

of the scan chain is 18 bits. In the Capture-DR state, the Flash Read Data buffer and the two status bits are loaded into the

shift registers and the Valid bit is cleared. The Error bit indicates any error that occurred during the write operation.

If the Valid bit read was cleared, the data and error fields should be ignored. If the Valid status (RO) bit is cleared and the

Valid control bit is set (WO) during the Update-DR state, the data is loaded into the Flash Write Data buffer, starting the data

write sequence to the flash. When the write is completed, a flash read is performed, placing the data in the Flash Read Data

buffer. The data is then compared to the Flash Write Data buffer; if the two are different, the Program Error flag in the Control

Status register and the Error flags in the data register are set. The Valid bit read (RO) indicates when another word may be

written to the data write buffer.

When the flash address is in the flash main block or Information block, the data written is one word (16 bits) and the address

increment is two.

FMBUSY is set at the beginning (Update-DR) of the write process; it is cleared when the write to the flash is completed. The

Flash error flags are updated in case an error occurs during the write operation.

Flash Erase

The Flash Erase instruction switches the data scan path to FL_ERASE register. During this instruction, the length of the scan

chain is two bits. In the capture-DR state, the Flash Busy and Error bits are read. If the Busy bit is cleared, the Error bit

indicates any failure in the erase process.

During the Update-DR state of this instruction, the Start (WO) bit is loaded into the Control register. If the Start bit and any

of the Erase bits are set, the respective erase process starts. The Flash Address and Block ID are used to indicate the page

or sector to erase in the Page and Sector Erase commands, respectively.

When the erase is completed, the Busy bit is set. The Error flag indicates any failure that occurs in the flash erase procedure.

The FMBUSY and FMERR bits in Flash Status register are updated in parallel to the Erase instruction Busy and Error flags.

Debugger Interface Instructions

SCAN_RX

The SCAN_RX instruction switches the data scan path to DBGDATA register. The DBGDATA length is set to L0 to L4; see

“Debug Data Register (DBGDATA)” on page 261. The result of the Capture-DR state of the TAP controller is unpredictable.

A parallel load of data from DBGDATA register to the DBGRXD Rx data buffer is done in Update-DR state.

The controller sets the RX_BUSY indication in DBGRXST register to 1 in Update-DR state. The PID and message fields of

the SCAN_RX instruction are available for read access, through the peripheral bus, from DBGRXST register. The ISE inter-

rupt control block asserts the ISE interrupt and RX_i bit in DBGISESRC register, according to the PID index.

DEBUGGER ABORT

This operation has no dedicated operation code. It is performed using the SCAN_RX instruction with the PID field is ‘1111’.

Following SCAN_RX mode, the ISE interrupt control block asserts ISE interrupts, together with ABORT_i bits in

DBGISESRC register, according to the MASKS values in DBGMASKS register. The assertion is triggered during the TCK

rising edge during Update-IR state. In this case, there is no RX_BUSY indication and no change in the contents of DB-

GRXST register (i.e., this format of SCAN_RX may be issued with a busy Rx data link).

SCAN_TX

The SCAN_TX instruction switches the data scan path to DBGDATA register. In Capture-DR state, DBGDATA register cap-

tures the values from the Tx data buffer DBGTXD. No parallel load is performed in Update-DR state. The length of

DBGDATA register is set to the value of MSG_LEN in DBGTXST register (see “Debug Data Register (DBGDATA)” on

page 261). No parallel load is performed in Update-DR state.

The Controller sets DBGTXLOC to all 1s and releases TINT on Update-DR state. This operation clears the semaphore and

enables the data link for a new transaction. TINT is asserted, as described in “TX Data Link” on page 250.

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SCAN_ABORT_MASK

The SCAN_ABORT_MASK instruction switches the data scan path to ABORT_MASK register. In Capture-DR state, a par-

allel update of the shift register occurs with the DBGMASKS values. Parallel load is performed in Update-DR state to update

the DBGMASKS values.

ASSERT_DBG_RST

A Debugger reset is asserted in Update-DR state. Serial data is switched to the BYPASS register.

4.19.7 TAP Data Registers, Debugger Interface

Bit Arrangement and Mapping

Figure 84 shows the bit allocation for a parallel load operation between any pair of serial shift registers and a peripheral bus

addressable register.

Figure 84. Bit Allocation Arrangement

Functionality in Various TAP Controller States

When data is shifted through a data register, data applied to TDI appears without inversion at TDO following an appropriate

number of TCK transitions, when the TAP controller is in Shift-DR state.

The data register connected between TDI and TDO shifts data one stage towards TDO after each rising edge of TCK in

Shift-DR state.

In TAP-Reset state, all data registers either perform their system function (if one exists) or do not interfere with the operation

of the on-chip system logic.

If, in response to the current instruction, a data register loads data from a parallel input, the data is loaded on the rising edge

of TCK following entry into Capture-DR state.

If the data register connected between TDI and TDO in response to the current instruction is provided with latched parallel

data outputs, the data is latched into the parallel output buffers on the falling edge of TCK, during Update-DR or Run-

Test/Idle states, as appropriate.

If, in response to a current instruction, no operation of a selected data register is required in a given controller state, the

When the TAP controller state machine is in TAP-Reset state during Power-Up reset, IR register is reset.

Data registers that are not selected by the current instruction are set to perform their functions, as described in Section 4.19;

specifically, see “TX Data Link” on page 250, “Debugger Reset Circuit” on page 250 and “ISE Interrupt Control” on page 250.

Table 40. Data Register Operation in Each Controller State

Controller State Action

Capture-DR Load data at parallel input into shift register stage. Parallel output registers, or latch, retains last state.

Shift-DR Shift data towards serial output. Parallel output register, or latch where provided, retains state.

Exit1-DR

Exit2-DR

Pause-DR

Retain last state.

Update-DR Load parallel output register or latch from the shift register stage. Shift register stage retains state.

All other controller

states Registers that have a parallel output maintain the last state of this output; otherwise undeﬁned.

15 0 15 0 15 0

TDI TDO

ADD XXXN ADD XXX(N-1) ADD XXX0

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Debug Bypass Register (BYPASS)

The BYPASS register provides a minimum length serial path for data movement between TDI and TDO. This path can be

selected when no other data register needs to be accessed.

The BYPASS register consists of a single shift register stage.

When the current instruction selects the BYPASS register for inclusion in the serial path between TDI and TDO, the shift

register stage is set to 0 on the rising edge of TCK following entry into Capture-DR state. The BYPASS register is accessed

from the JTAG serial bus only.

Debug Data Register (DBGDATA)

This register is the shift register element of DBGRXD and DBGTXD. It is accessed from the JTAG serial bus only. Figure 85

shows the parallel load data scheme.

The DBGDATA register consists of shift register stages according to the data buffer length. The actual length of the data value,

in a scan operation, is set before Capture-DR state when the current instruction is SCAN_RX or SCAN_TX. In the first case, it

is set according to SCAN_RX L0 to L4; in the latter case, it is set according to the value of MSG_LEN in DBGTXST register.

The actual length of the register is 16*(length+1), where “length” is the binary positive number created by the length field

(with L4 as MSB).

A length longer than the maximum data buffer is mapped to maximum length. A length shorter than the maximum data buffer

results in loading the data to/from the smallest addresses in the data buffer. Maximum length for this design is 128 shift reg-

ister stages. Note that TDO is always fixed; the TDI “insertion-point” changes according to the actual length.

Figure 85. DBGDATA Connection to the Data Links

Debug Abort Mask Register (DBGMASKS)

This is a serial shift register, with parallel output and parallel input (for read and write of ABORT_MASK register), accessed

by the JTAG serial bus while the SCAN_ABORT_MASK instruction is set to TAP IR. The register is not addressable from

the peripheral bus. The non-reserved bits of ABORT_MASK register are preset to 1 on Power-Up reset.

The ABORT_MASK register consists of shift register stages with 16 bits. Bits 1 to 15 are reserved and should be written with

0. A bit value of 1 enables the processor to abort; a bit value of 0 disables it.

Figure 86. ABORT_MASK and DBGMASKS Register Interaction

15 0 15 0 15 0

TDI TDO

ADD XXE ADD XXC ADD XX0

15 0

ADD XX2

DBGTXD

DBGDATA

DBGRXD

ADD YYE ADD YYC ADD YY0ADD YY2

15 0 15 0 15 015 0

Length = 1 word

Length = 8 words

15 0

TDI TDO

ABORT_MASK

DBGMASKS

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4.19.8 TAP Data Registers, Flash Interface

This section describes the flash interface registers available to the host through the flash interface. The bit ordering is as

described in “TAP Data Registers, Debugger Interface” on page 260.

Flash Control and Status Register (FL_CT_ST)

FL_CT_ST is a shift register that enables reading from the Flash Status register and writing to the Flash Control register.

The Flash Status register is read in Capture-DR state; the Flash Control register is updated in Update-DR state. The con-

nection of the register to the serial chain is shown in Figure 87. The Control and Status registers are reset at Power-Up and

TAP resets only.

Flash Status

Type: Varies per bit

Bit 76543210

Name FMPRGE BLFF FLAEN FMDERR FMBFULL FMBUSY FMPERR FMEERR

Reset 00000100

Bit 15 14 13 12 11 10 9 8

Name JTFIE DISVRF Reserved FMSPERE FMSERE FMPERE

Reset 00000000

Bit Type Description

0 R/W1C FMEERR (Flash Memory Erase Error). Indicates an error in erasing to the flash. It is cleared by

writing 1 to FMEERR bit in the Control register. This bit may be cleared only when FMBUSY bit is

cleared (0).

0: No program error detected (default)

1: An error occurred during erase

This bit may be cleared only when FMBUSY bit is cleared (0).

1 R/W1C FMPERR (Flash Memory Program Error). Indicates an error in writing to the ﬂash. It is cleared by

writing 1 to FMPERR bit in the Control register. This bit may be cleared only when FMBUSY bit is

cleared (0).

0: No program error detected (default)

1: An error occurred during program

2ROFMBUSY (Flash Memory Busy).

0: The embedded flash is ready to accept operations if no error flag is set

1: The embedded flash is not accessible because the PC87591x clocks are not ready or the embedded

ﬂash is busy programing or erasing

3ROFMBFULL (Flash Double-Buffer Full).

0: There is at least one empty word in the flash double buffer

1: The double-buffer is full

Figure 87. Flash Control and Status Register

15 0

TDI TDO

Flash Control Status

15 0

FL_CR_ST

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Flash Identiﬁcation Register (FL_ID)

FL_ID is a shift register that contains device identification information. This information can help to verify the use of the cor-

rect flash programing algorithm and to match downloaded information to the device properties.

Type: Read Only

4 R/W1C FMDERR (Flash Data Loss Error). Indicates that a double-buffer overrun error occurred. The bit is cleared

by writing 1 to FMDERR bit in Control register. It may be cleared only when FMBUSY bit is cleared (0).

0: No data loss detected (default)

1: A write to a full buffer was detected

5ROFLAEN (Flash Access Enabled).

0: The flash memory protection is set; read, write and erase (except special erase) are disabled

1: The flash memory access through the JTAG serial bus is enabled

6ROBLFF (Blank Flash Flag).

0: The Blank Flash flag is cleared and the core is allowed to execute from it

1: The Blank Flash flag is set and the core is kept in reset, even when flash access is enabled

7 R/W FMPRGE (Flash Memory Program Enable).

0: Programing the flash memory using JTAG write instructions is disabled (default)

1: Programing the flash memory using JTAG write instructions is enabled

8 R/W FFMPERE (Flash Memory Page Erase Enable).

0: Flash page erase disabled (default)

1: Flash page erase using the JTAG Erase instruction is enabled

9 R/W FMSERE (Flash Memory Sector Erase Enable).

0: Flash sector erase disabled (default)

1: Flash sector erase using the JTAG Erase instruction is enabled

10 R/W FMSPERE (Flash Memory Special Erase Enable).

0: Flash special erase operation disabled (default)

1: Flash special erase operation using the JTAG Erase instructions is enabled

13-11 Reserved.

14 R/W DISVRF (Disable Verify).

0: Enables verification of flash contents after program or erase (default)

1: Disables the automatic verification of flash contents after program or erase;

this speeds up the program or erase speed.

15 R/W JTFIE (JTAG To Flash Interface Enabled).

0: Flash access through the JTAG is disabled. Write of 1 to any other bit in this register is ignored, all

error flags are cleared, and all other JTAG access flash transactions are ignored (i.e., Capture-DR re-

turns invalid data, Update-DR is ignored) (default).

1: Interface to the flash through the JTAG is enabled

Bit 31 30 29 28 27 26 25 24 23 2 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Name Reserved SRID SID

Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ID values

Bit Type Description

Figure 88. Flash Identiﬁcation Register

32 0

TDI TDO

SID

FL_ID

SRID

15 0

Reserved

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Flash Address Register (FL_ADDR)

FL_ADDR is a shift register that enables reading from and writing to flash addresses. The address includes two fields: the

Flash Address and the Block Identifier (main block or information block). In Capture-DR state, the next address for read

and/or program is read. In case of a program or page erase fail, the offset within the section of the failing memory location

is returned. In Update-DR state, the address register is loaded with a new address. The connection of the register to the

serial chain is shown in Figure 89. The address register is reset at Power-Up and TAP resets only.

Type: R/W

Bit Description

7-0 SID (SuperI/O Identiﬁcation). Returns the value of SID register (see “SuperI/O ID Register (SID)” on page 344)

15-8 SRID (SuperI/O Revision ID). Returns the value of SID register (see “SuperI/O Revision ID Register (SRID)” on

page 346)

31-16 Reserved.

Bit 31302928272625242322120191817161514131211109876543210

Name Block ID Flash Address

Reset 0 0

Bit Type Description

27-0 R/W Flash Address. Holds the ﬂash address in bytes, starting from address 0000016. The ﬂash last address

depends on the block size. All addresses must be word aligned. Note that the ﬁeld may hold values larger

than the actual ﬂash size. Addresses beyond the ﬂash size are reserved and should not be speciﬁed.

31-28 R/W Block ID. Holds an ID for a speciﬁc block. The ID ﬁeld values are:

Bits

31 30 29 28 Description

0 0 0 0: For Capture-DR,reserved; for Update-DR, noload of Addressand Block IDregisters (default)

0 0 0 1: Flash Main Block

0 0 1 0: Flash Information Block

Other: Reserved

Figure 89. Flash Address Register

TDI TDO

Flash Address

27 0

FL_ADDR

Block ID

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Flash Data Register (FL_DATA)

FL_DATA is a shift register that enables scanning data for flash read and write. This register is used during both flash pro-

graming and flash read. It includes two fields: a 16-bit data field and two Control/Status bits. In Capture-DR state, data read

from the array (for either a read instruction or as a confirmation of a write cycle) is loaded from the Flash Read buffer into

FL_DATA register. The Valid and Error bits indicate if program and read operations are successfully completed. In Update-

DR state, data is loaded into the Flash Write Data buffer if the Valid bit in the data shifted in is set. The connection of the

Type: Varies per bit

Bit 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

Name Error Valid Data

Reset

Bit Type Description

15-0 R/W Data. In read, returns the data read from the ﬂash memory. Following a previous read instruction or a

set address, the data is read from the array with the currently held address. Following a previous write

instruction, the data is read back from the array as part of the write veriﬁcation.

During write instruction, data scanned into this ﬁeld, if the Valid bit is set, is loaded into the Flash Write

Data buffer and used for the next ﬂash programing action.

16 RO

Valid. Indicates that the data read or written is valid.

On Read (Capture-DR):

0: Data is not valid, since the read was not completed or the write buffer is not ready to accept new data.

1: Indicates that data in the Data Read buffer is valid. This data may be the result of a read (following a

previous read instruction) or the result of a failed write. Note that when a 1 is read from this bit, it is

automatically cleared to 0. In a read instruction, a read of 1 triggers a new read operation from memory

with the successive address.

During flash write sequences, indicates that the write data buffer is ready to accept new data; the bit

is cleared when new data is written to the buffer.

On Write (Update-DR): This bit must be written with 0 during a read instruction or when the flash is not

ready to accept new data (i.e., when the Valid bit in the Capture-DR is cleared).

0: Data is not valid. Do not update the Flash Data Write buffer.

1: Indicates that valid data is written to the Flash Data Write buffer. In write instruction, this triggers the

ﬂash to be programed with new data.

17 RO Error. Indicates that an error occurred during the last programing cycle. The bit is set when the error

is detected.

0: Last write was completed successfully (default)

1: An error was detected during the last write. This may be due to a failed write, a double buffer error or

to an attempt to violate restrictions put by the flash contents protection mechanism. For more details

about the error type, see “Flash Control and Status Register (FL_CT_ST)” on page 262.

When set, the error is cleared by clearing any set error flag in FL_CT_ST register.

Figure 90. Flash Data Register

17 0

TDI TDO

Flash Read Data Buffer

Flash Write Data Buffer

FL_DATA

Status

Control

15 0

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Flash Erase Register (FL_ERASE)

FL_ERASE is a shift register that starts a flash erase operation and returns the status of the erase operation. The type of

erase performed depends on the settings in the Control and Status register. The connection of the register to the serial chain

is shown in Figure 91. The FL_ERASE register is reset at Power-Up and TAP resets only.

Type: Varies per bit

Bit 1 0

Name Error Start/Busy

Reset 0 0

Bit Type Description

0RO

Busy. On read (Capture-DR), indicates the status of the flash array.

0: Flash is idle and is ready for an erase command to be started

1: Flash is busy executing a previous erase or write command; any command given at this state is ig-

nored.

Start. On write (Update-DR), starts a flash erase process.

0: Do not start a new erase process

1: Start a new erase process

1ROError. Indicates that an error occurred during the last erase cycle. This bit has valid data only when the

Busy bit is cleared.

0: Last erase was completed successfully (default)

1: An error was detected during the last erase. This may be due either to a failed erase or protection be-

ing set. More details about the error type are available by reading the Control and Status register.

When a value of 1 is read, this bit is cleared.

Figure 91. Flash Erase Register

TDI TDO

Status

Control

FL_ERASE

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4.19.9 Core Registers, Debugger Interface

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

Core Register Map

Debug Receive Data Registers 0, 2, 4, 6, 8, 10, 12 and 14 (DBGRXD0-14)

DBGRXD0 to DBGRXD14 is a group of eight word-wide read-only registers. The DBGRXD0-14 registers are written from

the JTAG serial bus. They can only be read from the peripheral bus. A representative DBGRXDi register is shown below.

Location: Channel 0 - 00 FDC016

Channel 2 - 00 FDC216

Channel 4 - 00 FDC416

Channel 6 - 00 FDC616

Channel 8 - 00 FDC816

Channel 10 - 00 FDCA16

Channel 12 - 00 FDCC16

Channel 14 - 00 FDCE16

Type: RO

Mnemonic Register Name Type

DBGRXD0-14 Debug Receive Data Registers 0, 2, 4, 6, 8, 10, 12 and 14 RO

DBGRXST Debug Receive Status Register Varies per bit

DBGTXD0-14 Debug Transmit Data Registers 0, 2, 4, 6, 8, 10, 12 and 14 R/W

DBGTXLOC Debug Transmit Lock Register R/W

DBGTXST Debug Transmit Status Register R/W

DBGTINT Debug TINT Assert Register WO

DBGABORT Debug Abort Generate Register WO

DBGISESRCA Debug ISE Source Register A R/W

Bit 1514131211109876543210

Name RX_DATAi

Bit Description

15-0 Receive Data (RX_DATA). Data bits 16*i through 16*i+15 of the Rx data link data buffer.

15 0

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Debug Receive Status Register (DBGRXST)

DBGRXST is a byte-wide register updated by the TAP controller to reflect the PID and MSG_LEN fields of the SCAN_RX

instruction. Bits 1 to 7 of this register are read-only bits; data written to them is ignored. The register format is shown below.

Location: 00 FDE016

Type: Varies per bit

Debug Transmit Data Registers 0, 2, 4, 6, 8, 10, 12 and 14 (DBGTXD0-14)

DBGTXD0 to DBGTXD14 is a group of eight word-wide read/write registers. The DBGTXD0-14 registers are written by a

processor from the peripheral bus. A representative DBGTXDi register is shown below.

Location: Channel 0 - 00 FDD016

Channel 2 - 00 FDD216

Channel 4 - 00 FDD416

Channel 6 - 00 FDD616

Channel 8 - 00 FDD816

Channel 10 - 00 FDDA16

Channel 12 - 00 FDDC16

Channel 14 - 00 FDDE16

Type: R/W

Bit 76543210

Name MSG_LEN PID RX_BUSY

Bit Type Description

0 R/W RX_BUSY (Receive Busy). Data link busy indication. This bit can be cleared by writing 1 to it. Writing

0 is ignored.

0: Not Busy

1: Busy

4-1 RO PID (Processor Index). A write operation to this ﬁeld is ignored.

Bit Value

(Decimal) Description

0: Processor ID index

1-14: Invalid

15: All processors abort

7-5 RO MSG_LEN. The message length equals (MSG_LEN+1). Write operations to this ﬁeld are ignored.

Bit 1514131211109876543210

Name TX_DATAi

Bit Description

15-0 TX_DATAi (Transmit Data i). Data bits i*16 through i*16+15 of the transmit buffer.

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Debug Transmit Lock Register (DBGTXLOC)

DBGTXLOC is a byte-wide read/write register. The PID field of this register is used as a semaphore for locking the Tx chan-

nel for a specific processor. If TINT is not active (1), this register is loaded with F16 on Warm or Internal reset. If TINT is

active (0), it is not affected by a Warm or Internal reset. At Power-Up reset, the register is always loaded with 0F16. The

Location: 00 FDE416

Type: R/W

Debug Transmit Status Register (DBGTXST)

DBGTXST is a byte-wide read/write register. This register is written by a processor to indicate the message length, which is

used by the Tx data link to set the length of the serial shift register and by the processor software to define the message

length parameter. While TINT is inactive, this register may be written to at any time. While TINT is active, the contents of

this register are locked and can be read by the host via the TAP controller status word MSG_LEN field. While TINT is inac-

tive, DBGTXST is cleared on reset. While TINT is active, only Power-Up reset clears DBGTXST. The register format is

shown below.

Location: 00 FDE216

Type: R/W

Bit 76543210

Name Reserved PID

Reset 0 0 001111

Bit Description

3-0 PID (Processor Index). Indicates which processor currently has control over the Tx channel. When TINT

becomes active, the value of PID is locked. On the Update_DR state of SCAN_TX instruction, PID is reset to

F16 after the host reads the data.

016-E16: Processor ID index. When the PID ﬁeld holds any of these values, write operations of values other

than F16 are ignored.

F16: Semaphore free indication. When the PID ﬁeld holds this value, write operations may capture the Tx

for processor use.

7-4 Reserved.

Bit 76543210

Name Reserved MSG_LEN

Bit 00000000

Bit Description

2-0 MSG_LEN (Message Length). The number of words in a message equals (MSG_LEN+1).

7-3 Reserved.

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Debug TINT Assert Register (DBGTINT)

This is a byte-wide write-only register used to assert TINT. The register format is shown below.

Location: 00 FDE616

Type: WO

Debug Abort Generate Register (DBGABORT)

DBGABORT is a word-wide write-only register, used to generate an ABORT. A processor may generate an ABORT to a

processor with a PID index of i by modifying its P_i bit to 1. Writing 0 to P_i does not result in ISE assertion. The register

format is shown below.

Location: 00 FDE816

Type: WO

Bit 76543210

Name Reserved ASSERT

Bit Description

0ASSERT (Assert TINT Control). Writing 1 to this bit asserts the TINT output. TINT is de-asserted during

Update_DR state of SCAN_TX or during Power-Up reset.

7-1 Reserved.

Bit 1514131211109876543210

Name Reserved Res Res Res Res Res Res Res P_0

Bit Type Description

0WOP_0. The ABORT source activation.

0: Processor ID i does not get an ABORT

1: Processor ID i gets an ABORT

15-1 Reserved. Reserved for future expansion.

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Debug ISE Source Registers A (DBGISESRCA)

DBGISESRCA is a word-wide read/write register that indicates the ISE sources. The register is cleared on reset. Writing 1

to a bit in this register clears it. Writing 0 to a bit does not change its value. The DBGISESRCA register format is shown

below.

Location: 00 FDEA16

Type: R/W S

4.19.10 Usage Hints

JTAG Performance

For best performance, the PC87591x should be the only device in the scan path. Since the Debugger interface is used in

the development phase of the product, this should not be a problem. Keep the scan path as short as possible.

JTAG Clock Rate

For reliable communication over the JTAG serial bus, the error probability should be extremely low. This can be achieved

by connecting the TAP to the JTAG bus controller card, paying attention to the TCK frequency, signal timing, this cable type

and cable length (for long cables, transceivers may be required).

Communication Lockout

Some erroneous operations by the host may cause a lockout of the communication hardware. Examples of such cases are:

●Performing a data scan when the JTAG instruction is SCAN_RX with a PID value of ‘1111’

●Performing a data scan with a JTAG instruction with a PID value that is not in the system (i.e., PID > 0)

●Performing a SCAN_TX when the PID value is ‘1111’

A reset instruction is guaranteed to recover from all of these locked cases, but it resets the entire PC87591x.

Bit 15 14 13 12 11 10 9 8

Name Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved

Reset 00000000

Bit 76543210

Name Reserved ABORT_0 RX_0

Reset 00000000

Bit Description

0RX_i. The ISE source is the Rx data link. Turn on with ISE assertion. Turn off by writing a byte to DBGISESRC

containing 1 in the RX_i bit location.

0: Not an ISE source

1: The ISE source is the Rx data link

1ABORT_i. The ISE source is an ABORT request by the debugger or one of the processors. This bit is set by

either an abort command from the debugger (SCAN_RX with PID=‘1111’) or by a write of a 1 to the processor’s

respective bit in DBGISECA register.

0: Not an ISE source

1: The ISE source is an ABORT event

7-2 Reserved. These bits are reserved for future expansion.

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4.20 DEVELOPMENT SYSTEM SUPPORT

The PC87591x supports code development and debug in the On Board Development (OBD) and Development (DEV) envi-

ronments. OBD environment is used for debug of the code in the final production board. DEV environment is used in Appli-

cation Development Boards (ADBs) and ISE systems.

4.20.1 Features

●ISE clipping support via a TRI-STATE strap input (TRIS)

Features available in OBD and DEV environments:

●Debugger interface via the JTAG based Debugger Interface module

●Internal ISE interrupt generation by the Debugger Interface module

●Internal Reset generation by the Debugger Interface module

●Ability to prevent real-time events from interfering with operation of ADB monitor

●Core-integrated hardware breakpoint

Features available in DEV environment:

●Optional use of break line input signal

●Status Information to trace internal activities and implement debug features such as hardware breakpoint and traces

●Use of SRAM in the ADB for fast download of code during development

Feature available in OBD environment:

●Use of on-chip ﬂash for executing the ﬁnal code

4.20.2 The ISE Interrupt

The core ISE interrupt is an edge-triggered, non-maskable interrupt that is triggered on the rising edge of the Debugger in-

terface output. The ISE interrupt is asserted by the Debugger Interface module for RX or ABORT events to the core.

The ISE interrupt is enabled in DEV and OBD environments when ON bit in DBGCFG register is set to 1; otherwise, it is held

inactive.

4.20.3 Break Line and Reset Output Interrupt

The BRKL_RSTO signal is available in DEV environment. It has two functions: BRKL interrupt input and RSTO reset indi-

cation. Multiplexing between the two functions is done based on bus activity as defined below.

BRKL Function

The BRKL interrupt input is enabled in DEV environment when ON and BRKLE in DBGCFG register are both set (1); other-

wise, it is held inactive.

When BRKL is active during an instruction fetch, it indicates to the core a request to break on the execution of the instruction

(if the instruction is to be executed). This enables implementing multiple hardware breakpoints using external hardware.

RSTO Function

RSTO is a pulse output that is driven low when the PC87591x is in reset due to any of its sources (i.e., any reset to the core).

This output may be used to set any required defaults in the development system.

RSTO and BRKL Selection

The BRKL_RSTO signal serves as input to the PC87591x whenever there is activity on the bus i.e., while either SELIO,

SEL0 or SEL1 are active. If SELIO, SEL0 or SEL1 are inactive, the system must stop driving the BRKL_RSTO signal and

hold it high using a pull-up resistor.

When there is no activity on the bus, BRKL_RSTO may serve as output. It is driven low during an internal reset. There may

be a delay from reset start to the signal being driven low, but it is guaranteed to be low for at least three CLK cycles.

4.20.4 TRIS Strap Input Pin

The TRIS strap input signal is used by ISEs to allow clipping on a PC87591x while it is mounted in the production system.

The TRIS input is sampled at VCC Power-Up reset while the device is in IRE or OBD environments. When TRIS is low (0),

the PC87591x acts normally. When TRIS is high (1), all PC87591x outputs, except for DAC outputs and 32KX2, are put in

TRI-STATE.

Section 2.3 on page 53 describes the strap input handling.

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4.20.5 Freezing Events

The PC87591x can prevent real-time events from interfering with the operation of the ADB monitor and changing the status

of the PC87591x. This is done by disabling maskable interrupts and setting FREEZE bit; the FREEZE bit freezes the

WATCHDOG counter and disables destructive read operations.

Disabling Maskable Interrupts

Clearing the core I or E bits in PSR register disables the maskable interrupts. The I bit is cleared automatically whenever a

trap or interrupt occurs and after reset.

Freezing the WATCHDOG Counter

To freeze the WATCHDOG counter, FREEZE bit in DBGCFG register must be set to 1 on entering a TMON routine (the bit

must be cleared before returning to the application). Setting FREEZE bit prevents the WATCHDOG from generating the re-

set that occurs if WATCHDOG is not cleared on time (see Section 4.10 on page 164). The WATCHDOG counter keeps its

value while it is frozen and resumes counting after FREEZE is cleared.

If an application fails to touch the WATCHDOG in time and a reset event is generated before or while FREEZE bit is set, the

PC87591x receives the reset.

Disabling Additional Modules

The two MFT16 and the two ACB modules may be frozen by the FREEZE bit. Freezing is enabled when the respective bit

in DBGFRZEN register is set; the bits can be set to meet specific needs of different applications.

Disabling Destructive Reads

When FREEZE in DBGCFG register is set (1), destructive reads do not change the system state (i.e., they return the read

data but do not clear or set bits or send signals). This allows the debugger to present the values of these bits. NMISTAT is

an exception to this rule and is not affected by FREEZE. Core accesses to Host domain registers (using the “Core Access

to Host Controlled Modules”) may also be destructive but are not affected by FREEZE. Note that host operations continue

without any FREEZE bit impact.

4.20.6 Monitoring Activity During Development

In DEV environment, information is available for monitoring on-chip activities and implementing debug features in the devel-

opment system.

Bus Status Signals

The Bus Status signals (BST2-0) indicate if a transaction on the core bus was issued and, if so, the type of transaction.

The BST2-0 signals reflect activity on the core bus. For word accesses involving 8-bit expansion memory, the core bus cycle

triggers two external bus cycles. The first external bus cycle is flagged as a T1 cycle of the core bus. The second is not

flagged as a T1 cycle, i.e., BST2-0 is 000. See Table 41.

Table 41. Core Bus Transaction Encoding

BST Core Bus Transaction Type

000 Not a T1 cycle, except when the core waits for an

interrupt following WAIT instruction execution

001 Core waits for an interrupt following WAIT

instruction execution

010 T1 of an interrupt acknowledge bus cycle

011 T1 of a data transfer of a non-core bus master

100 T1 of a sequential instruction fetch

101 T1 of a non-sequential instruction fetch

110 T1 of a core data transfer

111 T1 of an exception data transfer

Embedded Controller Modules (Continued)

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Transaction Effect on the External Bus

The following core bus transactions are reflected on the external bus:

●Accesses to external zones of expansion memory, off-chip base memory and accesses that use the I/O Expansion

protocol are indicated by the active state of the SEL0, SEL1 and SELIO signals, respectively, and are described by

the address and data buses and the status signals, BST2-0.

●Accesses to on-chip memories and peripheral modules can be observed using the “Core Bus Monitoring Bus Cycles”

(see “Core Bus Monitoring” on page 82). They accesses are indicated by an inactive state for the SEL0, SEL1 and/or

SELIO signals. They are described by addresses A0-19, the byte-enable BE0-1 signals, the CBRD signal and the

BST2-0 signals.

●BE0 is high when a lower memory byte (a byte in an even address) is accessed. BE1 is high when a higher memory

byte (a byte in an odd address) is accessed.

●CBRD is high when the transaction is a read operation and low when it is a write operation.

Pipe Status Signals (PFS and PLI)

The PFS indicates the completion of an instruction in the core. The Pipe Long Instruction (PLI) signal indicates the size of

the completed instruction, where 0 = word instruction and 1 = double-word instruction (see Figure 92). If an instruction flush-

es the pipeline, the fetch for the next instruction (BST=101) is issued during the cycle following the instruction’s PFS, or later.

4.20.7 On-Chip Hardware Breakpoint

The core provides two types of hardware breakpoints:

●Address Match - Detection of a matched address for the current executed instruction (PC value)

●Data Match - Detection of a read or write transaction for a matched memory location

For a detailed description of the core breakpoint mechanism, refer to the CR16B User Manual.

CLK

PFS

PLI

Instruction i

Completed Instruction i+1

Completed

Figure 92. Pipe Status Signal (PFS and PLI)

Embedded Controller Modules (Continued)

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4.20.8 CR16B Development Support Registers

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

CR16B Development Support Register Map

Debug Conﬁguration Register (DBGCFG)

The DBGCFG register controls the configuration of debug support features. On reset, DBGCFG is cleared (0).

Only the software development tools may access DBGCFG. This enables application software to be binary compatible in all

environments.

Location: 00 FF1616

Type: R/W

Mnemonic Register Name Type

DBGCFG Debug Conﬁguration R/W

DBGFRZEN Debug Freeze Enable R/W

Bit 76543210

Name Reserved BRKLE FREEZE ON

Reset 00000000

Bit Description

0ON.

0: In IRE environment, this bit is always cleared to 0; any data written to it is ignored. The ON bit becomes read-

only when DBGL bit in DCR register in the core is set.

1: In OBD and DEV environments, enables the following debug support features:

- ISE interrupt signal

- Use of other bits in DBGCFG register

1FREEZE.

0: No effect

1: When ON is 1, the WATCHDOG timer is stopped from counting. All bits that use destructive reads (i.e., bits set

or cleared by read operations and other events triggered by reads) become indifferent to reads. An exception

is NMISTAT register, which is always affected by reads. The DBGFRZEN register controls the impact of

FREEZE bit on a group of modules, enabling the group to be indifferent to the FREEZE being set. FREEZE has

no effect when ON is 0.

2BRKLE (Break Line Enable).

0: Break Line input is ignored by core

1: In DEV environment, when BRKLE is set, the BRKL input signal is passed to the core

7-3 Reserved.

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Debug Freeze Enable Register (DBGFRZEN)

The DBGFRZEN register enables the freeze operation to be performed on specific modules during debug. When the rele-

vant bit is set, it enables the freeze of activities in the respective module when both FREEZE and ON are set in DBGCFG

Location: 00 FF1816

Type: R/W

Bit 76543210

Name Reserved HIFEN USARTFEN ACB2FEN ACB1FEN MFT2FEN MFT1FEN

Reset 11111111

Bit Description

0MFT1FEN (MFT16 1 Freeze Enable).

0: FREEZE in DBGCFG register has no effect on the MFT16 1

1: Freezes the MFT16 1 when FREEZE is set

1MFT2FEN (MFT16 2 Freeze Enable).

0: FREEZE in DBGCFG register has no effect on the MFT16 2

1: Freezes the MFT16 2 when FREEZE is set

2ACB1FEN (ACB1 Freeze Enable).

0: FREEZE in DBGCFG register has no effect on the ACB 1 interface

1: Freezes the ACB 1 interface when FREEZE is set

3ACB2FEN (ACB2 Freeze Enable).

0: FREEZE in DBGCFG register has no effect on the ACB 2 interface

1: Freezes the ACB 2 interface when FREEZE is set

4USARTFEN (USART Freeze Enable).

0: FREEZE in DBGCFG register has no effect on the USART interface

1: Freezes the USART interface when FREEZE is set

5HIFEN (Host Interface Freeze Enable).

0: FREEZE in DBGCFG register has no effect on the Host Interface module

1: Freezes the Host interface when FREEZE is set

7-6 Reserved.

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5.0 Host Controller Interface Modules

This chapter describes functions that serve as an interface between the host and core domains. The functions are:

●Keyboard and Mouse Controller Interface (legacy 6016,64

16); see Section 5.1

●Two Power Management (PM) channels compliant with ACPI EC speciﬁcations; see Section 5.2 on page 285

●Shared Memory mechanism; see Section 5.3 on page 297

●Core Access to SuperI/O modules; see Section 5.4 on page 313

●Mobile System Wake-Up functions; see Section 5.5 on page 318

5.1 KEYBOARD AND MOUSE CONTROLLER INTERFACE

The PC87591x supports a standard Keyboard and Mouse Controller interface. This interface implements legacy ports 6016

and 6416.

5.1.1 Features

●Intel 8051SL-compatible Host interface

—8042 KBD standard interface (ports 6016, 6416)

—Legacy IRQ: IRQ1 (KBD) and IRQ12 (mouse) support

—Fast Gate A20 and Fast Reset via ﬁrmware

●Conﬁgured using two logical devices: Keyboard and Mouse

5.1.2 General Description

The PC87591x supports a keyboard/mouse communication channel that uses the standard command/status register and

data registers. It uses either polling- or interrupt-driven communication schemes with the host and/or core. The hardware is

designed to allow a race-free interface between the host and the PC87591x.

The keyboard and mouse channel consists of three registers:

●DBBOUT - can be written by the core and read by the host processor.

●DBBIN - can be written by the host processor and read by the core.

●STATUS - can be read by both core and host processors. It has ﬁve bits (2, 4-7) that are written by the core. Three

other bits are controlled by the hardware to indicate the status of DBBIN and DBBOUT registers.

Host Addresses

The host processor accesses the PC87591x Keyboard/Mouse Host Interface registers at two addresses in the host address

space. These addresses are defined by two internal chip-select signals specified in the PC87591x host configuration regis-

ters; see Section 6.1.10 on page 348). Legacy settings of these addresses are 6016 and 6416 for the status/command and

data registers, respectively.

Table 42 describes the register mapping to the host processor I/O space. For simplicity, the Host Interface module specifi-

cation refers to the legacy addresses.

Table 42. Mapping of the Host Interface Registers to the Host Processor

Core Interrupts

The Host Interface module generates four level (high) interrupts to the core ICU. These can be used by the firmware for

interrupt-driven control of the keyboard/mouse and/or PM channels.

Host Interrupts

The PC87591x Host Interface supports two interrupts to the host processor: Keyboard interrupt (legacy IRQ1) and Mouse

interrupt (legacy IRQ12). These interrupts may be controlled by hardware according to the host interface buffer status or by

the PC87591x firmware toggling the bit value.

Port Legacy

Address Internal Chip Select Type Register Name Mnemonic

Keyboard and

Mouse 6016 Keyboard/Mouse Data Write Data DBBIN (A2=0)

6416 Keyboard/Mouse Command Write Command DBBIN (A2=1)

6016 Keyboard/Mouse Data Read Data DBBOUT

6416 Keyboard/Mouse Command Read Status STATUS

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The Host configuration module assigns host interrupts to IRQ numbers (see Section 6.1.10 on page 348). These interrupts

are IRQ1 and IRQ12 for keyboard and mouse IRQs, respectively.

When IRQ1 and/or IRQ12 are disabled (OBFKIE and/or OBFMIE bits in HICTRL register are cleared), the firmware can con-

trol the IRQ1 and/or IRQ12 signals by writing to the signal’s respective bit in HIIRQC register.

When IRQ1 and/or IRQ12 are controlled by hardware (OBFKIE and/or OBFMIE bits in HICTRL register are set to 1), inter-

rupts to the host are generated according to the status of Output Buffer Full (OBF) flag.

In normal polarity mode (IRQNPOL in HIIRQC register is set to 0), the PC87591x supports two types of interrupts: Legacy

Edge and Level. When an Edge interrupt is selected (IRQM in HIIRQC register is set), the interrupt signal default value is

high (1). When an interrupt signal must be sent (i.e., the corresponding OBF flag is set), a negative pulse is generated. The

pulse width is determined by IRQM field in HIIRQC register.

When the IRQ signals are set as level interrupts (IRQM in HIIRQC register is set to 0), the interrupt signal is usually low (0)

and is asserted (1) to indicate that the respective OBF flag is set. The signal is de-asserted (0) when the output buffer is read

(i.e., OBF flag is cleared).

Note that IRQ1 and IRQ12 have the same OBF flag but are not asserted together. Either IRQ1 or IRQ12 is set, depending

on the internal register written (HIKDO or HIMDO, respectively).

In negative polarity mode (IRQNPOL in HIIRQC register is set to1), the IRQ signal behavior is inverted from the behavior

described above.

The PC87591x firmware can read the values of the IRQ1 and IRQ12 signals by performing a read operation from IRQ1B

and IRQ12B bits in HIIRQC register.

Figure 93 illustrates the effect of the different control bits on the IRQ signals.

Figure 93. IRQx (IRQ1, IRQ11 or IRQ12) Control Diagram

Keyboard/Mouse Channel (6016, 6416)

The Host Interface of the PC87591x is compatible with the legacy 8042 host interface. It is based on two registers: Com-

mand/Data and Status. The Host Interface logic generates interrupts to the host processor and core according to the status

of the input and output data buffers. Figure 94 provides a schematic description of the Host Interface Keyboard/Mouse chan-

nel.

Hardware

IRQM field (HIIRQ)

Interrupt

IRQNPOL bit (HIIRQC)

IRQxB bit (HIIRQC)

OBFMIE or OBFKIE bit

(HICTRL)

IRQxB bit (HIIRQC)

(write) (Part of SuperI/O

Configuration

Module)

IRQ Routing

and Polarity

IRQ Serializer IRQ

Serializer

(read)

5.0 Host Controller Interface Modules (Continued)

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Status Read

Both the host and the core can read the status of the KBC data buffers. Bits 2 and 4 to 7 can be written by the core. The

host processor should read address 6416 to obtain the contents of the Status register. The core software can obtain this

information by reading/writing the HIKMST register. The format of the Status register is identical for both the host and the

core (see “Host Interface Keyboard/Mouse Status Register (HIKMST)” on page 284).

Host Data Write to Host Interface Keyboard/Mouse Channel

The data buffer has two latches; one serves as an input buffer and the other as an output buffer. When writing to address

6016 or 6416, the following sequence of events occurs: the data is written to the Data In latch (DBBIN), IBF bit in the Status

register is set and bit 3 (A2) in the Status register indicates to the core which address (command or data) was written to.

When writing to address 6016 (legacy A2=0), bit 3 of the Status register is cleared. When writing to address 6416 (legacy

A2=1), bit 3 of the Status register is set.

The core identifies that data is present in the input buffer by either polling IBF bit of the Status register or acknowledging an

interrupt when the input buffer interrupt is enabled (IBFCIE in HICTRL register is set to 1).

When the input buffer is full, reading the Status register identifies which address was written to (i.e., check A2 of HIKMST

register). The core can then read the data from the input buffer (HIKMDI). The IBF status bit is cleared when the data input

buffer is read by the core.

Host Data Read from Host Interface Keyboard/Mouse Channel

The output data latch (DBBOUT) is written by the core when it needs to send data to the host. The OBF flag in the Status

register (OBF in HIKMST register) is set to indicate that data is available in DBBOUT. DBBOUT should be written only when

this bit is cleared.

The PC87591x supports polling and interrupt communication schemes with the host. Both Keyboard interrupt (IRQ1) and

Mouse interrupt (IRQ12) are supported.

The core firmware writes to HIKDO register data addressed to the keyboard driver (i.e., generate IRQ1). A write to HIKDO

stores the data to DBBOUT and sets OBF bit. If the IRQ1 interrupt is enabled (OBFKIE in HICTRL register is set to 1), it is

also sent according to the interrupt mode (IRQM field and IRQNPOL bit in HIIRQC register).

The core firmware writes data addressed to the mouse driver (IRQ12) to HIMDO register. A write to HIMDO stores the data

in DBBOUT and sets OBF bit. If the IRQ12 interrupt is enabled (OBFMIE in HICTRL is set to 1); the IRQ12 interrupt is also

sent according to the interrupt mode (IRQM field and IRQNPOL bit in HIIRQC register).

DBBIN

DBBOUT

STATUS

D0-7

D0-7 A2

Host-WR-Data-Buffer

Host-RD-Data-Buffer

WR-Mouse WR-KBD RD-Input

Buffer

Input Buffer

Full

Output Buffer

Empty

Interrupts to the Core

(IRQ1)

Peripheral Bus

SIB Bus

Interrupts to the Host Processor

Figure 94. Host Interface Keyboard/Mouse Channel (Ports 60,64) Block Diagram

Keyboard Mouse

(IRQ12)

through SuperI/O Configuration

Interrupt Request Interrupt Request

5.0 Host Controller Interface Modules (Continued)

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The host processor identifies that data is present in the output buffer by either polling the Status register (reading address

6416) or responding to IRQ1 or IRQ12. When this data is available, the host can read it using a read operation from address

6016. Reading from address 6016 clears the OBF flag. In addition, when the host interrupt is in level mode (IRQM in HIIRQC

The core can read OBF bit to identify when the output buffer is empty and ready for a new data transfer. When the Output

Buffer Empty interrupt to the core is enabled (OBECIE in HICTRL register is set to 1), the interrupt signal to the ICU is set

high if the output buffer is empty (OBF=0).

5.1.3 Host Interface Registers

The module has four registers, described below. The base address for each may be configured individually. For legacy op-

eration, they should be configured to 6016 and 6416 (see Section 6.1.10 on page 348).

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

Host Interface Register Map

Data Out Buffer Register (DBBOUT, Legacy 6016)

This register allows the host to read DBBOUT register while clearing OBF bit in the Status register. If the host interrupts are

level (IRQM in HIIRQC register is 0002), the interrupt is de-asserted. If the core interrupt on output buffer empty is enabled

(OBECIE in HICTRL register is set to 1), reading this register asserts it (high).

Location: As defined in LDN 0616 registers, index 6016 and 6116

Type: R

Offset Mnemonic Register Name Type

6016 DBBOUT Data Out Buffer R

6416 STATUS Status R

6016 DBBIN Data In Buffer W

6416 COMAND Command In Buffer W

Bit 76543210

Name Keyboard/Mouse DBBOUT Data

Bit Description

7-0 Keyboard/Mouse DBBOUT Data.

5.0 Host Controller Interface Modules (Continued)

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Status Register (STATUS, Legacy 6416)

This register provides the status of the host interface keyboard channel buffers (DBBIN and DBBOUT) and the value of mes-

sages sent by the core using the Status bits to the host. The Status register can also be read by the core as HIKMST. The

Status register is cleared (0016) on reset.

Location: As defined in LDN 0616 registers, index 6216 and 6316

Type: R

Data In Buffer Register (DBBIN, Legacy 6016)

This register allows the host to write to DBBIN register while setting Status register bit IBF and clearing Status register bit

A2 bit. If the core interrupt on IBF is enabled (IBFCIE in HICTRL register is set to 1), writing to this register asserts it (high).

Location: As defined in LDN 0616 registers, index 6016 and 6116

Type: W

Command In Buffer Register (COMAND, Legacy 6416)

This register allows the host to write to DBBIN register while setting IBF and A2 bits in the Status register. If the core interrupt

on IBF is enabled (IBFCIE in HICTRL register is set to 1), writing to Data In Buffer asserts it (high).

Location: As defined in LDN 0616 registers, index 6216 and 6316

Type: W

Bit 76543210

Name ST3-ST0 A2 F0 IBF OBF

Reset 00000000

Bit Description

0OBF (Output Buffer Full). The bit is set when the keyboard/mouse channel’s DBBOUT is written to the core

(i.e., writing to HIKDO or HIMDO registers). The bit is cleared by a host processor read from the

keyboard/mouse channel output buffer (6016).

1IBF (Input Buffer Full). The bit is set when the keyboard/mouse channel’s DBBIN is written to the host

processor (i.e., writing to either address 6016, data or address 6416, control). The bit is cleared when the core

reads the input buffer (HIKMDI).

2F0 (Flag 0). A general-purpose flag that can be set or cleared by the core firmware.

3A2 (A2 Address). Holds the value of the A2 signal in the last write operation of the host to the keyboard/mouse

channel’s input buffer (i.e., A2=0 for Data In Buffer write and A2=1 for Command In Buffer write).

7-4 ST3-ST0 (Status). Four general-purpose flags that can be set or cleared by the core firmware.

Bit 76543210

Name Keyboard/Mouse DBBIN Data

Bit Description

7-0 Keyboard/Mouse DBBIN Data.

Bit 76543210

Name Keyboard/Mouse DBBIN Data

Bit Description

7-0 Keyboard/Mouse DBBIN Data.

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5.1.4 Core Interface Registers

Some register bits affect PM channel 1 to achieve firmware compatibility with the PC87570.

For a summary of the abbreviations used for Register Type, see Section 2 on page 34.

Core Interface Register Map

Host Interface Control Register (HICTRL)

The HICTRL is used in setting host interface mechanism options. On reset, non-reserved bits of HICTRL are cleared.

Location: 00 FEA016

Type: R/W

Mnemonic Register Name Type

HICTRL Host Interface Control R/W

HIIRQC Host Interface IRQ Control R/W

HIKMST Host Interface Keyboard/Mouse Status R/W

HIKDO Host Interface Keyboard Data Out Buffer WO

HIMDO Host Interface Mouse Data Out Buffer WO

HIKMDI Host Interface Keyboard/Mouse Data In Buffer RO

Bit 76543210

Name Reserved PMICIE PMIOCIE PMIHIE IBFCIE OBECIE OBFMIE OBFKIE

Reset 00000000

Bit Description

0OBFKIE (Output Buffer Full Keyboard Interrupt Enable).

0: IRQ1 is controlled by IRQ1B bit in HIIRQC register

1: Enables the Output Buffer Full interrupt to the keyboard driver of the host processor (IRQ1). The interrupt is

triggered by a core write to HIKDO register and sent according to IRQM field and IRQNPOL bit in HIIRQC reg-

ister.

1OBFMIE (Output Buffer Full Mouse Interrupt Enable).

0: IRQ12 is controlled by IRQ12B bit in HIIRQC register

1: Enables the Output Buffer Full interrupt to the mouse driver in the host processor (IRQ12). The interrupt is trig-

gered by the core write to HIMDO register and sent according to IRQM field and IRQNPOL bit in HIIRQC reg-

ister.

2OBECIE (Output Buffer Empty Core Interrupt Enable).

0: Interrupt signal is low

1: Enables the Output Buffer Empty interrupt to the core ICU for the keyboard/mouse channel. The interrupt signal

is active when the output buffer is empty (i.e., the interrupt signal is set (1) when OBF bit is cleared).

3IBFCIE (Input Buffer Full Core Interrupt Enable).

0: Interrupt signal is low

1: Enables the Input Buffer Full interrupt to the core ICU for the keyboard/mouse channel. The interrupt signal is

active when the input buffer is full (i.e., the interrupt signal is set (1) when IBF bit is set).

4PMIHIE (PMI Channel 1 Host Interrupt Enable).

0: IRQ11 is controlled by IRQ11B bit in HIIRQC register

1: Enables the Output Buffer Full interrupt of PM channel 1 in PC87570 Compatible mode, to drive the host pro-

cessor interrupt. The interrupt is noted as IRQ11 and may be routed to any of the IRQs, to SMI or to the SCI

events. The interrupt is triggered by a core write to HIPM0DO register and sent according to IRQM field and

IRQNPOL bit in HIIRQC register.

5.0 Host Controller Interface Modules (Continued)

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Host Interface IRQ Control Register (HIIRQC)

The HIIRQC register controls the IRQ signals mode of operation. On reset, HIIRQC is set to 0716.

Location: 00 FEA216

Type: R/W

5PMOCIE (PM Channel 1 Output Buffer Empty Core Interrupt Enable).

0: Interrupt signal is low

1: Enables the PM Output Buffer Empty interrupt to the core ICU for PM channel 1 in PC87570 Compatible mode.

The interrupt signal is active when the output buffer is empty (OBF bit is cleared in the PM channel status reg-

ister).

6PMICIE (PM Channel 1 Input Buffer Full Core Interrupt Enable).

0: Interrupt signal is low

1: Enables the PM input buffer full interrupt to the core ICU for PM channel 1 in PC87570 Compatible mode. The

interrupt signal is active when the input buffer is full (IBF bit is set in the PM channel status register).

7Reserved.

Bit 76543210

Name Reserved IRQNPOL IRQM IRQ11B IRQ12B IRQ1B

Reset 00000111

Bit Description

0IRQ1B (Host Interrupt Request 1 Control Bit). When the IRQ1 signal is conﬁgured for direct control by the

ﬁrmware (OBFKIE in HICTRL register is 0), IRQ1B bit is output to the IRQ1 signal. When read, IRQ1B bit

returns the current value of the IRQ1 pin. The IRQ1 signal value an be read regardless of the state of OBFKIE

bit.

1IRQ12B (Host Interrupt Request 12 Control Bit). When the IRQ12 signal is conﬁgured for direct control by the

ﬁrmware (OBFMIE in HICTRL register is 0), IRQ12B bit is output to the IRQ12 signal. When read, IRQ12B bit

returns the current value of the IRQ12 pin. The IRQ12 signal value can be read regardless of the state of the

OBFMIE bit.

2IRQ11B (Host Interrupt Request 11 Control Bit). When PM channel 1 is in PC87570 Compatible mode and

its host interrupt is configured for direct control by the firmware (PMHIE in HICTRL register is 0), IRQ11B bit is

output to the IRQ11 signal. When read, IRQ11B bit returns the current value of the IRQ11 signal. The IRQ11

signal value can be read regardless of the state of PMHIE bit; see Section 5.2 on page 285 for details about the

PM channel 1 interrupt scheme.

5-3 IRQM (IRQ Mode). Sets the hardware-controlled IRQ signals to work in Level or Pulse mode and deﬁnes the

pulse width in Pulse mode.

When IRQM = 0002, the IRQ signals function in Level mode. In this mode, when IRQNPOL = 0, the signal’s

default value is low, and a high level is set to issue an interrupt (the respective OBF is set).

When IRQM ≠0, the host interrupts are in Pulse mode. When IRQNPOL = 0, the signal’s default value is high

and toggles low to issue an interrupt (i.e., when the respective output buffer register is written). The pulse width

is as follows:

Bits

5 4 3 Pulse Width

0 0 0: Level Interrupt

0 0 1: 1-Cycle Pulse

0 1 0: 2-Cycle Pulse

0 1 1: 4-Cycle Pulse

1 0 0: 8-Cycle Pulse

1 0 1: 16-Cycle Pulse

Other: Reserved

Bit Description

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Host Interface Keyboard/Mouse Status Register (HIKMST)

The HIKMST register provides the status of the Host Interface keyboard channel buffers (DBBIN and DBBOUT) and a way

for the PC87591x to send status bits to the host. This register can also be read by a host processor read operation from

address 6416. On reset, the register is cleared.

Location: 00 FEA416

Type: R/W

Host Interface Keyboard Data Out Buffer Register (HIKDO)

The HIKDO register allows the core firmware to write to DBBOUT register while setting OBF bit in the Status register. If IRQ1

interrupt is enabled, it is sent. If the core interrupt on output buffer empty is enabled (OBECIE in HICTRL register is 1), writing

to HIKDO de-asserts it (low).

Location: 00 FEA616

Type: WO

6IRQNPOL (Negative Polarity). When IRQNPOL is cleared, the IRQ (IRQ1, IRQ11, IRQ12) signal polarity is

compatible with the standard ISA bus interface (as specified in the IRQM field). When hardware IRQ generation

is enabled (HICTRL register bits OBFKIE for IRQ1 and IRQ12; PMHIE for IRQ11), the interrupt output is

inverted if IRQNPOL is set.

7Reserved.

Bit 76543210

Name ST3-ST0 A2 F0 IBF OBF

Reset 0 0000

Bit Description

0OBF (Output Buffer Full). The bit is set when the keyboard/mouse channel’s DBBOUT is written by the core

(i.e., writing to HIKDO or HIMDO register). The bit is cleared by a host processor read from the keyboard/mouse

channel output buffer (6016). This read-only bit is ignored when writing to this register.

1IBF (Input Buffer Full). The bit is set when the keyboard/mouse channel’s DBBIN is written by the host

processor, i.e., writing to either address 6016 (data) or address 6416 (control). The bit is cleared by a core read

of the input buffer (HIKMDI). This read-only bit is ignored when writing to this register.

2F0 (Flag 0). A general-purpose ﬂag that can be set or cleared by the core ﬁrmware.

3A2 (A2 Address). Holds the value of the A2 signal in the last write operation of the host to the keyboard/mouse

channel’s input buffer (i.e., indicates A2 value during write to address 6016 or 6416). This read-only bit is ignored

when writing to this register.

7-4 ST3-ST0 (Status Bits). Four general-purpose ﬂags that can be set or cleared by the core ﬁrmware.

Bit 76543210

Name Keyboard DBBOUT Data

Bit Description

7-0 Keyboard DBBOUT Data.

Bit Description

5.0 Host Controller Interface Modules (Continued)

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Host Interface Mouse Data Out Buffer Register (HIMDO)

The HIMDO register allows the core firmware to write to the DBBOUT register while setting OBF bit in the Status register. If

an IRQ12 interrupt is enabled, it is sent. If the core interrupt on output buffer empty is enabled (OBECIE in HICTRL register

is 1), writing to HIMDO de-asserts it (low).

Location: 00 FEA816

Type: WO

Host Interface Keyboard/Mouse Data In Buffer Register (HIKMDI)

The HIKMDI register allows the core firmware to read to the DBBIN register while clearing IBF bit in the Status register. If

the core interrupt on IBF is enabled (IBFCIE in HICTRL register is 1). Reading from HIKMDI de-asserts it (low).

Location: 00 FEAA16

Type: RO

5.2 POWER MANAGEMENT (PM) CHANNELS

The PC87591x implements two PM communication channels, both of which are compliant with ACPI specifications for an

embedded controller interface. The PC87591x may be configured to work in either Private Interface or Shared Interface

mode. The PM interface has two identical channels, which are individually configured and used. If using only one channel,

Shared Interface mode should be used; if using both channels, Private Interface mode may be used.

The description below refers to a single channel. The signals may have the suffix ‘n’ to indicate the channel number, either

1 or 2, where applicable. Registers in the core domain have the prefix HIPMn to indicate the channel number. Host domain

registers are identified by the logical device to which they belong.

Note: When working in PC87570 Compatible mode, only channel 1 may be used.

5.2.1 Features

●Two operation modes

—PC87570 Compatible

—Enhanced PM

●ACPI embedded controller interface compliant support

—Shared interface

—Private interface

●PM channel registers (legacy 6216,66

16)

—Command/Status

—Data

●PM interrupt using

—IRQ

—SMI

—SCI

Bit 76543210

Name Mouse DBBOUT Data

Bit Description

7-0 Mouse DBBOUT Data.

Bit 76543210

Name Keyboard/Mouse DBBIN Data

Bit Description

7-0 Keyboard/Mouse DBBIN Data.

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5.2.2 General Description

The PM channel has two modes of operation:

●PC87570 Compatible (available for channel 1 only) supports software previously written for the PC87570.

●Enhanced PM includes a mechanism that facilitates easier generation of SCI and SMI interrupts to the host.

Figure 95 is a schematic diagram of the PM channel.

Data Registers

The PM channel has three registers.

●DBBOUT - can be written to by the core and read by the host processor. Multiple addresses in the core address

space enable generating an IRQ, SMI or SCI interrupt on Output Buffer Full (OBF).

●DBBIN - can be written to by the host processor and read by the core.

●STATUS - can be read by both the core and the host processor. It has ﬁve bits (bits 2 and 4-7) that are written to by

the core directly or, in Enhanced PM mode, via the control and conﬁguration register. Three other bits are controlled

by hardware to indicate the status of DBBIN and DBBOUT registers.

Host Addresses

The host processor accesses the PC87591x PM channel interface registers at two addresses in the host address space.

These addresses are defined by two internal chip select signals specified in the PC87591x Host configuration registers; see

Section 6.1.13 on page 355 and Section 6.1.14 for channels 1 and 2, respectively. Legacy setting of these addresses is 6216

and 6616 for channel 1 Status/Command and Data registers, respectively.

Table 43 shows the register mapping to the host processor I/O space. For simplicity, the Host Interface module specification

refers to the legacy addresses.

DBBIN

DBBOUT

Status

D0-7

IRQ

Peripheral Bus

SIB Bus

Input Buffer

Full

Output Buffer

Empty

Interrupts to the Core

Interrupt to the Host Processor

Host-WR-Data Buffer

Host-RD-Data-Buffer

Figure 95. Host Interface PM Channel n Block Diagram

SMI SCI

Command/Status

or Data

WR-PM RD-PM

Buffer

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Table 43. Host Interface Registers to Host Processor Mapping

Core Interrupts

For each channel, the Host Interface module generates two level (high) interrupts to the core ICU (see Figure 96). The firm-

ware can use these for interrupt-driven control of the PM channels.

In PC87570 Compatible mode (EME in HIPMnCTL register is set to 0), interrupts are enabled using HICTRL register bits

PMOCIE and PMICIE for output buffer empty and input buffer full interrupts, respectively.

In Enhanced PM mode (EME in HIPMnCTL register is set to1), interrupts are enabled using HIPMnCTL register bits OBEIE

and IBFIE for output buffer empty and input buffer full interrupts, respectively.

Host Interrupt Generation Modes

The Host Interface module generates three types of interrupts to the host: regular IRQ, SMI and SCI. The interrupt schemes

are designed to meet ACPI requirements for host interrupts. Two interrupt modes are supported: PC87570 Compatible and

Enhanced PM.

PC87570 Compatible Mode

PC87570 Compatible mode uses the same method for IRQ generation as the PC87570. It is available only for PM channel 1

and is enabled when EME in HIPMnCTL register is set to 0. Figure 98 illustrates this scheme.

The host configuration module assigns host interrupts to IRQ numbers (see Section 6.1.13 on page 355). IRQ11 is used as

an example interrupt and for the signal naming (the actual interrupt number used is determined by the IRQ routing logic).

When hardware-driven IRQ11 is disabled (PMHIE in HICTRL register is cleared), the firmware can control the IRQ11 signal

by writing to the signal’s respective bit in HIIRQC register. When hardware-driven IRQ11 is enabled (PMHIE is set to 1),

interrupts to the host are generated according to the status of the OBF flag.

Port Legacy

Address1

1. The legacy address serves as an example only. Do not assign the same address for both channels.

Conﬁguration

Select Type Register

Name Mnemonic

Channel n 6216 Index 6016,61

16 Data Write Data DBBIN

6616 Index 6216,63

16 Command/Status Write Command DBBIN

6216 Index 6016,61

16 Data Read Data DBBOUT

6616 Index 6216,63

16 Command/Status Read Status STATUS

IBF bit (HIPMnST)

EME bit (HIPMnCTL)

OBF bit (HIPMnST)

PMOCIE bit (HICTRL)

OBEIE bit (HIPMnCTL)

PMICIE bit (HICTRL)

IBFIE bit (HIPMnCTL)

PMnOBE

Interrupt

PMnIBF

Interrupt

ICU

Figure 96. Core Interrupt Request for PM Channel n

EME bit (HIPMnCTL)

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In Normal Polarity mode (IRQNPOL in HIIRQC register is cleared), the PC87591x supports two types of interrupts: legacy

edge or legacy level. When an edge interrupt is selected (IRQM field in HIIRQC register is set to a value other than 0), the

interrupt signal default value is high (1). When an interrupt signal must be sent (i.e., OBF flag is set), a negative pulse is

generated. The pulse width is determined by the same field, IRQM, that selects the edge interrupt.

When a level interrupt is selected (IRQM in HIIRQC register is cleared), the interrupt signal is usually low (0). It is asserted

(1) to indicate that the respective OBF flag has been set. The signal is de-asserted (0) when the output buffer is read (i.e.,

OBF flag is cleared).

In Negative Polarity mode (IRQNPOL in HIIRQC register is set to 1), IRQ signal behavior is inverted from the behavior de-

scribed for normal polarity.

The PC87591x firmware can read the value of the IRQ11 signal by performing a read operation of IRQ11B bit in HIIRQC

The core can also control the routing of interrupts generated by the PM channel to one of the following:

●IRQ signal, when IRQE bit in HIPMnIE register is set

●SMI output, when SMIE bit in HIPMnIE register is set

●SCI event, using the SCIEC output, when SCIE bit in HIPMnIE register is set.

The core firmware should not enable more than one of these interrupts simultaneously. It should also update ST0 and ST1

bits to indicate the type of host interrupt used.

Enhanced PM Mode

Enhanced PM mode is available for both PM channels. It is enabled when EME in HIPMnCTL register is set to 1. Figure 98

illustrates interrupt generation in this mode.

Either IRQ, SMI or SCI interrupts may be generated under software control or by using hardware. Using hardware reduces

software overhead and simplifies procedures.

The mechanism that generates the IRQ is identical to that used in PC87570 Compatible mode. To enable identical control

of both channels, the bits that are used for channel 1 are separated from the keyboard/mouse channel’s registers; see

Figure 98 for bit usage.

IRQE in HIPMnIE register determines if an IRQ is sent from PM Channel n.

Enhanced PM mode supports direct generation of SCI and SMI on core writes to the Data output buffer and generation of

SCI on core reading of the Data Input buffer. The core decides whether to generate an interrupt and which type of interrupt

to generate by selecting the data register address in use.

When data is written to HIPMnDO register, the OBF flag in HIPMnST register is set and neither SMI nor SCI is generated.

Hardware

IRQM field (HIIRQ)

Interrupt

IRQNPOL bit (HIIRQC)

IRQ11B bit (HIIRQC)

PMHIE bit (HICTRL)

IRQ11B bit (HIIRQC)

(Part of SuperI/O

Configuration

Module)

IRQ Routing

and Polarity

IRQ

Serializer

IRQE bit (HIPMnIE)

SMIE bit (HIPMnIE)

SCIE bit (HIPMnIE)

Gathering

SMI Source

Gathering

SCI Source

SMI

ECSCI

Figure 97. IRQ, SCI and SMI Control in PC87570 Compatible Mode (PM Channel 1 Only)

OBF

SMIPOL bit (HIPMnIC)

SCIPOL bit (HIPMnCTL)

(write)

(read)

(Level or Edge) (Polarity)

(Hardware or Firmware)

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When data is written to HIPMnDOM register, the OBF flag and the internal OBF_SMI flag are set and an SMI interrupt is

generated. The OBF_SMI flag is cleared when OBF flag is cleared. The SMI is generated as a pulse whose width is defined

by PLMM in HPIMnIC register.

The SMI interrupt is routed to the SMI pin only if both HSMIE and SMIE bits in HIPMnIE register are set. When SMIE is set

and HSMIE is cleared, SMIB in HIPMnIC register is used as the PMnSMI signal value. When SMIE is cleared, the PMnSMI

signal is inactive (high).

When data is written to HIPMnDOC register, the OBF flag and OBF_SCI internal flag are set and an SCI interrupt is gener-

ated. OBF_SCI is cleared when OBF is cleared. The SCI is generated as a pulse whose width is defined by PLMS in

HPIMnCTL register.

When data is read from HIPMnDIC register, the IBF flag is cleared, the IBF_SCI Internal flag is set and an SCI interrupt is

generated. The IBF_SCI flag is cleared when the IBF is set again. The SCI is generated as a pulse whose width is defined

by PLMS in HPIMnCTL register. Reading from HIPnDI register clears the IBF flag but does not generate an SCI interrupt.

Note that IBF_SCI flag may also be set by writing a 1 to SCIIS bit in HIPMnIC register. This is done to start an SCI interrupt

on input buffer empty without a read operation from the input buffer.

The SCI interrupt is routed to the SCI pin only if HSCIE and SCIE in HIPMnIE register are set. When SCIE is set and HSCIE

is cleared, the value of SCIB in HIPMnIC register is used as the PMnSCI signal value. When SCIE is cleared, PMnSCI is

inactive (high).

Status Read

The status of the PM channel data buffers can be read by both the host and the core. Bits 2 and 4-7 can be written by the core.

The host processor should read the Status register I/O address (legacy 6616, for channel 1) to obtain the contents of the Status

register. The core software should read/write the HIPMnST register to access the same information. The format of the Status

Hardware

IRQM field (HIIRQC)

Interrupt

IRQNPOL bit (HIIRQC)

IRQB bit (HIPMnIC)

(Part of

Module)

IRQ

and

IRQE bit (HIPMnIE)

SMIE bit (HIPMnIE)

Gathering

SMI

OBF bit

SuperI/O

Config

Routing

Polarity

IRQ

Serializer

IRQB bit (HIPMnIC)

HIPMnDOM (write)

HIPMnDI (read)

HIPMnDO (write)

HIPMnDIC (read)

set OBF_no_int

set OBF_SMI

HIPMnDOC (write) set OBF_SCI

clear IBF bit (HIPMnST)

SMIB bit (HIPMnIC)

SCIB bit (HIPMnIC)

Pulse Shape

Figure 98. IRQ, SCI and SMI Control, Enhanced PM Mode

PLMM field (HIPMnIC)

PLMS field (HIPMnCTL)

HSMIE bit (HIPMnIE)

HSCIE bit (HIPMnIE)

HIRQE bit (HIPMnIE)

PMnSMI

Pulse Shape

Source

ECSCI

set IBF_SCI

SCIIS bit (HPMnIC)

(write 1)

SMIPOL bit (HIPMnIC)

SCIPOL bit (HIPMnCTL)

SCIE bit

PMnECSCI of

other channel

PMnECSCI

SCIB bit (HIPMnIC) (read)

SMIB bit (HIPMnIC)

(write)

(read)

(HIPMnIE)

(HIPMnST)

(read)

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Host Data Write to Host PM Channel

The data buffer has two latches: one serves as an input buffer and the other serves as an output buffer. When writing to the

Command (legacy address 6616) or Data (legacy address 6216) registers, the following sequence occurs: data is written to

the Data In latch (DBBIN), IBF bit in the Status register is set and bit 3 (A2) in the Status register indicates to the core which

of the two addresses was written to. When writing to the data register address, A2 bit of the Status register is cleared (0).

When writing to the Command register address, A2 bit in the Status register is set (1).

The core identifies that data is present in the input buffer by either polling IBF bit in the Status register or acknowledging an

interrupt when the input buffer interrupt is enabled (IBFCIE bit in HICTRL register is set to 1).

When the input buffer is full, the Status register should be read to identify which addresses were written to by checking A2

bit in HIPMnST register. The core can then read the data from the input buffer (HIPMnDI or HIPMnDIC registers). The IBF

status bit is cleared when the data input buffer is read by the core.

Host Data Read from Host Interface Power Management Channel

The core writes to the Output Data latch (DBBOUT) when it needs to send data to the host. The OBF flag in the Status reg-

ister (HIPMnST) is set to indicate that data is available in DBBOUT. DBBOUT should be written to only when OBF in

HIPMnST register is cleared.

The PC87591x supports polling and interrupt communication schemes with the host. IRQ, SMI or SCI interrupts may be

used. The core firmware writes data addressed to the PM drivers to the HIPMnDO register. When working in Enhanced PM

mode, writes to HIPMnDOC and HIPMnDOM may be used to automatically generate SCI and SMI, respectively. Refer to

“Host Interrupt Generation Modes” on page 287 for details of the interrupt generation scheme.

The host processor identifies the presence of data in the output buffer by either polling the Status register or by responding

to IRQ, SMI or SCI events. When such data is available, the host can read it using a read operation from the address of the

data register (legacy 6216 for channel 1). Reading from the data register clears the OBF flag (HIPMnST). In addition, when

the host interrupt is in level mode (IRQM in HIIRQC register is set to 0002) and the hardware interrupt is enabled, the IRQ

signal is de-asserted (low).

The core can read OBF in HIPMnST register to identify when the output buffer is empty and ready for a new data transfer.

When the output buffer empty interrupt to the core is enabled (PMOCIE bit in HICTRL register is 1 when EME bit in HIP-

MnCTL register is 0), the interrupt signal to the ICU is set high if the output buffer is empty (OBF is set to 0).

5.2.3 Core PM Registers

For a summary of the abbreviations used for Register Type, see Section 2 on page 34.

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Core PM Register Map

Host Interface PM n Status Register (HIPMnST)

The HIPMnST register contains the status of the host interface PM channel buffers (DBBIN and DBBOUT). It also provides

a means for the PC87591x to send status bits to the host. This register is read by a host processor read operation from ad-

dress 6616. HIPMnST is cleared on reset.

Location: Channel 1 - 00 FEAC16

Channel 2 - 00 FEBE16

Type: Varies per bit

Mnemonic Register Name Type

HIPMnST1

1. Where n stands for register 1 or 2.

Host Interface PM n Status Varies per bit

HIPMnDO1Host Interface PM n Data Out Buffer WO

HIPMnDOC1Host Interface PM n Data Out Buffer with SCI WO

HIPMnDOM1Host Interface PM n Data Out Buffer with SMI WO

HIPMnDI1Host Interface PM n Data In Buffer RO

HIPMnDIC1Host Interface PM n Data In Buffer with SCI RO

HIPMnCTL1Host Interface PM n Control R/W

HIPMnIC1Host Interface PM n Interrupt Control R/W

HIPMnIE1Host Interface PM n Interrupt Enable R/W

Bit 76543210

Name ST3-ST0 A2 F0 IBF OBF

Reset 00000000

Bit Type Description

0ROOBF (Output Buffer Full). The bit is set when the PM channel’s DBBOUT is written to by the core

(writing to HIPMnDO, HIPMnDOM or HIPMnDOC register). The bit is cleared by a host processor read

of the output buffer (6216). Writing to this bit is ignored.

1ROIBF (Input Buffer Full). The bit is set when the PM channel’s DBBIN is written to by the host

processor (writing to either address 6216 or address 6616). The bit is cleared by a core read of the PM

input buffer (HIPMnDI or HIPMnDIC).

2 R/W F0 (Flag 0). General-purpose flag that can be set or cleared by the core firmware.

3ROA2 (A2 Address). Indicates whether the last write operation of the host to the PMn channel was to the

data register or the Command register. Writing to this bit is ignored.

0: Last write was to the data register (pointed to by conﬁguration register index 6016 and 6116)

1: Last write was to the command register (pointed to by conﬁguration register index 6216 and 6316)

7-4 R/W ST3-ST0 (Status). Four general-purpose ﬂags that can be used for signaling between the host and

core. When used as an embedded controller interface channel for ACPI, a predeﬁned meaning is

assigned to ST0, ST1 and ST2. The standard meaning is BURST, SCI event and SMI event,

respectively.

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Host Interface PM n Data Out Buffer (HIPMnDO)

The HIPMnDO register allows the core firmware to write to the PM port DBBOUT register while setting the PM port OBF bit

in the Status register. If enabled, an IRQ11 (and/or SCI and/or SMI, in PC87570 Compatible mode) interrupt is sent at that

time. If the core interrupt on PM port output buffer empty is enabled, writing to HIPMnDO de-asserts it (low). If DMA on output

buffer empty is enabled, the DMA request is de-asserted on the write to HIPMnDO.

Location: Channel 1 - 00 FEAE16

Channel 2 - 00 FEC016

Type: WO

Host Interface PM n Data Out Buffer with SCI (HIPMnDOC)

The HIPMnDOC register has the same function as the HIPMnDO register. In addition, it generates an SCI interrupt when

OBF is set and hardware SCI generation is enabled.

Location: Channel 1 - 00 FEB216

Channel 2 - 00 FEC416

Type: WO

Host Interface PM n Data Out Buffer with SMI (HIPMnDOM)

The HIPMnDOM register has the same function as the HIPMnDO register. In addition, it generates an SMI interrupt when

OBF is set and hardware SMI generation is enabled.

Location: Channel 1 - 00 FEB416

Channel 2 - 00 FEC616

Type: WO

Bit 76543210

Name PM Channel DBBOUT Data

Bit Description

7-0 PM Channel DBBOUT Data.

Bit 76543210

Name PM Channel DBBOUT Data

Bit Description

7-0 PM Channel DBBOUT Data.

Bit 76543210

Name PM Channel DBBOUT Data

Bit Description

7-0 PM Channel DBBOUT Data.

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Host Interface PM n Data In Buffer (HIPMnDI)

The HIPMnDI register allows the core firmware to read the PM port DBBIN register while clearing the PM port IBF bit in the

Status register. If the core interrupt on IBF for the PM channel is enabled, reading from HIPMnDI de-asserts it (low).

Location: Channel 1 - 00 FEB016

Channel 2 - 00 FED216

Type: RO

Host Interface PM n Data In Buffer with SCI (HIPMnDIC)

The HIPMnDIC has the same function as the HIPMnDI register. In addition, it generates an SCI interrupt when IBF is cleared

and when hardware SCI generation is enabled.

Location: Channel 1 - 00 FEB616

Channel 2 - 00 FEC816

Type: RO

Bit 76543210

Name PM Channel DBBIN Data

Bit Description

7-0 PM Channel DBBIN Data.

Bit 76543210

Name PM Channel DBBIN Data

Bit Description

7-0 PM Channel DBBIN Data.

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Host Interface PM n Control Register (HIPMnCTL)

The HIPMnCTL register controls the operation mode and configuration of the PM channel. It includes the Enhanced mode

enable bit and control bits for Enhanced mode operation. HIPMnCTL is 4016 on reset.

Location: Channel 1 - 00 FEB816

Channel 2 - 00 FECA16

Type: R/W

Bit 76543210

Name EME SCIPOL PLMS Reserved OBEIE IBFIE

Reset see text 1000000

Bit Description

0IBFIE (Input Buffer Full Interrupt Enabler).

0: IBF interrupt to the core is disabled

1: Enables an interrupt to the core when IBF in HIPMnST register is set

1OBEIE (Output Buffer Empty Interrupt Enable).

0: OBF interrupt to the core is disabled

1: Enables an interrupt to the core when OBF in HIPMnST register is set

2Reserved.

5-3 PLMS (Pulse Level Mode SCI). Sets the hardware-controlled SCI signal mode to be Level or Pulse and sets

the pulse width.

When PLMS = 0002, the SCI signal functions in Level mode. In this mode, the SCI pulse shaper output value is

low, and a high level is set to issue an interrupt (the respective OBF is set).

When PLMS ≠0, the host interrupts are in Pulse mode. In this mode, the SCI pulse shaper output value is low,

and it toggles high to issue an interrupt (i.e., when the respective output buffer register is written).

The pulse widths are:

Bits

5 4 3 Pulse Width

0 0 0: Level interrupt

0 0 1: 1-Cycle Pulse

0 1 0: 2-Cycle Pulse

0 1 1: 4-Cycle Pulse

1 0 0: 8-Cycle Pulse

1 0 1: 16-Cycle Pulse

Other: Reserved

6SCIPOL (SCI Negative Polarity).

0: SCI output inactive value is low and its active (asserted) value is high

1: Inverted polarity is used. When SCIPOL is set, the SCI signal is the inverse of either what is stored in SCIB or

the output of the SCI pulse shaper.

This bit affects the SCI signal polarity in both PC87570 Legacy and Enhanced modes.

7EME (Enhanced Mode Enable).

0: PM channel is used in Legacy mode. HIPMnST status bits are controlled by writes to the bit value, and inter-

rupts are controlled by HICTRL and HIIRQC register bits (default for HIPM1CTL).

1: Enables enhanced control of the PM channel. The bits in HICTRL and HIIRQC registers are ignored in this case

(default for HIPM2CTL).

In HIPM2CTL (i.e., for PM channel 2), EME is a read-only bit that holds the value 1. Writes to this bit are

ignored.

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Host Interface PM n Interrupt Control Register (HIPMnIC)

The HIPMnIC register and its bits affect operation in Enhanced mode only (i.e., when EME bit in HIPMnCTL register is set).

In PC87570 Legacy mode, the bits in this registers are ignored. HIPMnIC controls the PM n interrupt signals mode of oper-

ation. HIPMnCTL is 4116 on reset.

Location: Channel 1 - 00 FEBA16

Channel 2 - 00 FECC16

Type: R/W

Bit 76543210

Name SCIIS SMIPOL PLMM SCIB SMIB IRQB

Reset 01000001

Bit Description

0IRQB (Host Interrupt Request Control Bit). When the IRQ signal is conﬁgured for direct control by the

ﬁrmware (HIRQE in HIPMnIE register is 0), IRQB bit is output to the PMnIRQ signal. When read, IRQB bit

returns the current value of the PMnIRQ signal. IRQn signal’s value can be read regardless of the state of

HIRQE in HIPMnIE register.

1SMIB (Host SMI Request Control Bit). When the SMI signal is conﬁgured for direct control by the ﬁrmware

(HSMIE in HIPMnIE register is 0), SMIB bit is output to the PMnSMI signal (if SMIPOL=0, SMIB is output; if

SMIPOL=1, SMIB is inverted before output). When read, SMIB bit returns the current value of the SMI pin. The

SMI signal’s value can be read regardless of the state of HSMIE in HIPMnIE register.

2SCIB (Host SCI Request Control Bit). When the SCI signal is conﬁgured for direct control by the ﬁrmware

(HSCIE in HIPMnIE register is 0), SMIB bit is output to the PMnSCI signal (if SCIPOL=0, SCIB is output; if

SCIPOL=1, SCIB is inverted before output). When read, SCIB bit returns the current value of the SCI pin. The

ECSCI signal value can be read regardless of the state of HSCIE bit in HIPMnIE register.

5-3 PLMM (Pulse Level Mode SMI). Sets the hardware-controlled SMI signal mode to Level or Pulse and sets the

pulse width.

When PLMM = 0002, the SCI signal functions in Level mode. In this mode, the SMI pulse shaper output value is

low, and a high level is set to issue an interrupt (i.e., the respective OBF is set).

When PLMM ≠0, the host interrupts are in Pulse mode. In this mode, the SMI pulse shaper output value is low,

and it toggles high to issue an interrupt (i.e., when the respective output buffer register is written).

The pulse widths are:

Bits

5 4 3 Pulse Width

0 0 0: Level interrupt

0 0 1: 1-Cycle Pulse

0 1 0: 2-Cycle Pulse

0 1 1: 4-Cycle Pulse

1 0 0: 8-Cycle Pulse

1 0 1: 16-Cycle Pulse

Other: Reserved

6SMIPOL (SMI Negative Polarity).

0: SMI output inactive value is low and its active (asserted) value is high

1: Inverted polarity is used. When SMIPOL is set, the SMI signal is either the inverse of what is stored in SMIB or

the output of the SMI pulse shaper.

This bit affects the SMI signal polarity in both PC87570 Legacy and Enhanced modes

7SCIIS (SIC on IBF Start). A write of 1 to this bit starts an SCI interrupt on IBF cleared. A write of 0 to SCIIS is

ignored. When read, this bit always return 0.

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Host Interface PM n Interrupt Enable Register (HIPMnIE)

The HIPMnIE register controls the PM n interrupt signals that enable SMI, SCI and IRQ interrupts. HIPMnIE is cleared on reset.

Location: Channel 1 - 00 FEBC16

Channel 2 - 00 FECE16

Type: R/W

Bit 76543210

Name Reserved HSMIE HSCIE HIRQE SMIE SCIE IRQE

Reset 00000000

Bit Description

0IRQE (IRQ Enable).

0: PMnIRQ signal assumes its default value (low) and no interrupts are issued

1: Enables PM generation of IRQ events

1SCIE (SCI Enable).

0: PMnSCI signal assumes its default value (high) and no interrupts are issued

1: Enables PM generation of SCI events

2SMIE (SMI Enable).

0: PMnSMI signal assumes its default value (high) and no interrupts are issued

1: Enables the generation of SMI events by this module

3HIRQE (Hardware IRQ Enable). Works only in Enhanced PM mode.

0: IRQB bit of HIPMnIC register controls the value of the IRQ

1: Enables the generation of IRQ events by hardware control based on the status of the OBF flag

4HSCIE (Hardware SCI Enable). Works only in Enhanced PM mode.

0: SCIB bit in HIPMnIC register controls the value of the SCI

1: Enables the generation of SCI events by hardware control based on the status of the OBF and IBF flags

5HSMIE (Hardware SMI Enable). Works only in Enhanced PM mode.

0: SMIB bit in HIPMnIC register controls the value of the SMI

1: Enables the generation of SMI events by hardware control based on the status of the OBF flag

7-6 Reserved.

Host Controller Interface Modules (Continued)

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5.3 SHARED MEMORY AND SECURITY

The PC87591x on-chip flash can be shared by the host and the core. It may also be used by the host for BIOS code storage

or other purposes. The on-chip flash resides in the core domain. In IRE and OBD environments, it is accessible via the core

bus. For host accesses, the flash is mapped to the host memory address space via the host interface, and a bridge is pro-

vided between the host bus and the core bus. The bridge functionality includes:

●Memory mapping between host domain address space and core domain address space

●Host bus to core bus transaction bridging

●Locking mechanism between host and core domains to maintain coherence of on-chip ﬂash contents during updates

●Read/write protection on host accesses to the on-chip ﬂash

●Host-accessible control and status registers of on-chip ﬂash

●Signaling interface for host-core communication associated with memory updates

In addition, the PC87591x supports expansion memory controlled by the core domain’s Bus Interface Unit (BIU). The bridge

also supports host accesses to the expansion memory (including read/write protection on these accesses). These accesses

can occur in IRE, OBD and DEV environments.

In the PC87591S, the Shared Memory and Security module also includes a Random Number Generator (RNG). The output

of the RNG is available to the core.

5.3.1 Host Bus to Core Bus Access Translation

A core bus transaction is generated for each of the following types of host bus transactions:

●8-bit memory read/write

●8-bit FWH memory read/write

●8-bit indirect read/write transactions, using I/O read/write to access the shared ﬂash (see Section 5.3.3 on page 300)

Memory and FWH memory read/write transactions drive Long Wait on the Sync field until the transaction is completed on

the core bus. Section 5.3.3 on page 300 describes the Sync field for indirect memory read/write transactions. Section 5.3.5

on page 301 describes the behavior for restricted accesses.

The host bus transaction is forwarded to the core bus after the following is done:

●Address is translated

●The translated address and the access type are veriﬁed to be both:

—In core domain’s base memory or expansion memory spaces

—Unprotected

●For writes (erase/program): on-chip ﬂash is unlocked (HLOCK bit in SMCCST register is set)

Note that host bus read transactions are translated to read transactions on the core bus, and host bus write transactions are

translated to write transactions on the core bus. Translated reads and writes behave the same as reads and writes by the

core. When the erase bit is set and the on-chip flash is enabled and addressed, the effect of a write is the same as a write

after the page erase bit is set.

5.3.2 Memory Mapping and Host Address Translation

Section 6.1.11 on page 349 describes in detail the host domain addresses for which the core bus generates transactions.

In general, the BIOS memory on the host bus can occupy one of three regions in the memory space (see Table 60 on

page 350).

Address translation between the host and the core domains is performed for host memory and FWH memory transactions.

The 32-bit address received from the host bus is used to decode the different zones, as described in Section 6.1.11 on

page 349. The address is then translated to the core bus address using the following rules:

●Legacy and Extended Legacy BIOS Range

Handle only when enabled (see Section 6.1.11 on page 349 for the enabling alternatives); otherwise, transactions to

this zone are ignored. The address is converted to a shared memory internal address as follows:

SM_Host_Address[31-0] = {1111 1111 1111 111, Host_Memory_Address[16-0]}

●User Deﬁned Shared Memory Space

This address range is handled only when enabled (see Section 6.1.11 on page 349 for the enabling alternatives);

otherwise, transactions to this zone are ignored. The address translation depends on the window size deﬁned. When

the window size is 2nbytes, the lower ‘n’ bits are taken from the memory address, and the upper 32 −n bits of the

LPC address are replaced with 1. The address is converted to an internal address as follows:

SM_Host_Address[31-0] = {1111 ... ... 1, Host_Memory_Address[n-0]}

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●386 Mode-Compatible BIOS Range and User Deﬁned Shared Memory Range

This address range is handled only when enabled (see Section 6.1.11 on page 349 for the enabling alternatives);

otherwise, transactions to this zone are ignored. The address is converted to an internal address as follows:

SM_Host_Address[31-0] = Host_Memory_Address[31-0]

●Indirect Memory Address

This address speciﬁed in IMA3-0 is used as follows:

SM_Host_Address[31-0] = {IMA3[7-0], IMA2[7-0], IMA1[7-0], IMA0[7-0]}

●For allowed addresses, the SM_Host_Address is translated to a core address using the following equation

(a 21-bit address in the core address space is generated by adding the host memory address to the MBTA):

CR_Space_Address[20-0] = (21 least signiﬁcant bits)(SM_Host_Address + MBTA)

MBTA is the size of the PC87591x on-chip flash memory, as defined in the Shared Memory Main Block Top Address

may be changed to allow code development for other flash sizes.

●The CR_Space_Address[21-0] is checked against the Host-Controlled Access Protection registers, the Core-Con-

trolled Override Protection registers and general address space access limitations (i.e., space not mapped to the

base memory or expansion memory).

Figure 99 illustrates the address translation scheme for shared memory transactions.

Access restrictions are based on the contents of the host-controlled and core-controlled access protection registers. The

access protection logic may prevent read and/or write access to addresses in the core address space. The core-controlled

register setting should always prevent host access to addresses that are not in the core domain’s base memory or expansion

memory spaces. Note that the resulting memory space is not continuous.

In DEV environment, the value of MBTA may be changed for ease of software development. The memory space between

MBTA (1 000016 in PC87591E or 2 000016 in PC87591S) to F FFFF16 is not accessible by the host.

The following figures illustrate the mapping function that results from the address translation function for a Shared BIOS

scheme (Figure 100) and when the flash is mapped as a non-BIOS block of memory (Figure 101).

FWH ID Check

Address

Translation

LPC

Bus

Transaction Type &

Memory Address

Decoders

MUX

0-16

17-31

“1”

Legacy & Extended

BIOS Range

Memory R/W

Address

MBTA

Indirect Memory Access

Reset or

IMA0-3

Core Write

Access

Protection

Logic

Access

Protection

Registers

Override

Protection

Registers

0-20

0-31

Core Bus

Address

Host-Controlled Core-Controlled

Figure 99. Address Translation Mechanism for 512 Kbyte On-Chip Flash

MBTA

0-20

SM_Host_Address

386 BIOS Range

0-31

0-(win_size_bits − 1)

win_size_bits − 31

“1” User Def. Space

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00 000016

Main Block Top Address (MBTA)

1F FFFF16

FFFF FFFF16

FFFF FFFF16 - MBTA

FFE0 000016

Expansion Memory

On-Chip Flash

10 000016

00 E00016

01 000016

FFF0 000016 - MBTA

0000 000016

000F FFFF16

Reserved (Out-of-Range)

Host Address Core Address

Legacy BIOS

Extended

Legacy BIOS

000F 000016

000E FFFF16

000E 000016

Figure 100. Host to Core Address Translation: 386 Mode-Compatible BIOS Range

Numbers (1,2) indicate the links

between host memory and core

memory maps.

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5.3.3 Indirect Memory Read and Write Transaction

The following I/O mapped registers can be utilized instead of memory mapping to perform a core bus transaction using an

LPC I/O transaction:

●Four Indirect Memory Address registers (IMA3-IMA0), representing host address bits 31 to 0

●One Indirect Memory Data register (IMD), representing data bits 7 to 0

An LPC I/O write to the IMD register triggers a core bus memory write cycle using the addresses and data from IMA3-IMA0

and IMD registers, respectively. The LPC I/O write is completed when the core bus transaction is completed.

An LPC I/O read cycle from IMD register triggers a core bus memory read cycle using the addresses from IMA3-IMA0. The

data returned from the core bus cycle is used to complete the LPC I/O read cycle from IMD register.

Read/write cycles from/to IMA3-IMA0 registers drive Short Wait on the Sync field. Read/write cycles from/to IMD register

drive Long Wait on the Sync ﬁeld until a transaction is actually performed and completed on the core bus.

Indirect memory read/write transactions are subject to the same memory mapping, locking mechanism and host access pro-

tection as memory and FWH memory read/write transactions. For more details, see Sections 5.3.2, 5.3.4 and 5.3.5.

5.3.4 Locking Between Domains

For read operations, hardware handles arbitration between the host and core. For program and erase operations, the

PC87591x provides the means for enabling exclusive use for any particular access path over a sequence of operations.

By default, the core has access permission to the on-chip flash, and the HLOCK bit is cleared (0). In this case, if a program

or erase operation starts, any host read operation is deferred or aborted, as defined by HERES field in SMCCST register.

When host erase or program operation is required, the Signaling interface (Section 5.3.7 on page 303) or one of the other

host/core communication channels should be used to request control of the flash from the core. The core should go into a

state in which the flash is not written or erased and then set the HLOCK bit. Note that core reads from the flash may be

delayed in this case; therefore, it is recommended for critical code to be copied to RAM. Once the host access to the flash

is completed, the host should indicate this to the core, allowing it to clear the HLOCK bit and resume normal operation.

00 000016

Main Block Top Address (MBTA)

1F FFFF16

F FFFF16

F FFFF16 - MBTA

0 000016

10 000016

00 E00016

01 000016

0 000016 - MBTA

Host Address Core Address

Figure 101. Host to Core Address Translation: Non-BIOS Mode

Expansion Memory

On-Chip Flash

Reserved (Out-of-Range)

Numbers (1,2) indicate the links

between host memory and core

memory maps.

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The core can clear HLOCK bit at any time, preventing any further erase or program operations by the host.

5.3.5 Host Access Protection

The host read/write protection is software controlled via a set of registers accessible to the host. The protection granularity

is per block. Each of the 32 software-controlled protection blocks is 64 Kbytes; the block’s read protection and write protec-

tionflags may be set independently. A Lock Protect flag may be setto prevent future changes to the read andwrite protection

bits. Once locked, the lock bit and the read/write enable bits may be changed only after Host Domain Hardware reset.

The core can override the host settings and prevent host access to certain areas of the shared memory. The override may

be set independently for read and write. In the first 128 Kbytes of address space, each core-controlled block is 8 Kbytes. For

the rest of the memory space the blocks are 64 Kbytes each.

The default value of the protection registers is set according to the properties of the block. There are three types of blocks:

●Core Boot Block:Read, Erase and Program protected from the host.

●Host Boot Block:Open for Read by the host; Erase and Program protected from the host.

●Other Blocks:Open for Read, Erase and Program by the host.

Core on-chip peripherals and RAM are never accessible to the host (for both read and write). The range from MBTA to

0 FFFF16 should be protected from host access using the core-controlled protection registers.

The size of any of the above blocks is defined as part of the flash protection information. This information is stored in the

flash information block at address FE16. This information is updated while the flash is programed or during a Special Erase,

through either the JTAG or Parallel Interface.See Section 4.16.6 on page 226 for information about protection information

fields.

Core Boot Block

This block is not accessible by the host and (for either read nor write). The core boot block starts at address 0 000016 and

ends as defined in the protection information field (8 Kbytes to 128 Kbytes in steps of 8 Kbytes). The core boot block access

protection settings may not be changed, and the respective protection bits are read only.

Host Boot Block

By default, this block may be read by the host. Host writes to this block are always disabled. The host boot block size is

64 Kbytes and is available when the Host Boot Block bit in the protection word is cleared. The Host boot block is always the

last 64 Kbytes of the base memory (i.e., MBTA −64 Kbytes to MBTA −1 Kbyte). In case of an overlap between the host

boot block and the core boot block, access protection settings of the core boot block are used. The host boot block access

protection settings may not be changed, and the respective protection bits are read only.

Other Blocks

By default, all other blocks are read and write protected. The core may enable host read and/or write access to these blocks.

Setting the Host Access Protection Flags

There are two sets of host access protection flags, as shown in Figure 102:

●Host-controlled host access protection ﬂags

●Core-controlled host access protection ﬂags

Host-Controlled Host Access Protection Flags. For each of the 32 protection blocks there is a set of three bits (flags):

Read Protect, Write Protect and Lock Protect. The 32 sets of flags are accessible via two registers, Shared Memory Host

Access Protect Register 1 and 2 (SMHAP1-2), using an indexing scheme.

The Host Block index may be calculated using the following equation:

Host_Block_Index = CR_Space_Address[20-0] / 64K or

Host_Block_Index = (21 least signiﬁcant bits)(SM_Host_Address + MBTA) / 64K

See Section 5.3.2 on page 297 for the definitions of the host address translation.

●To change a ﬂag setting, write the new ﬂag setting, together with the required index ﬁeld (i.e., Host Access Protection

Index) and a cleared Index Write bit, to the appropriate register (SMHAP1 or SMHAP2).

●To read the values of the ﬂags:

1. Read the value of the register and save the index ﬁeld.

2. Write the index of the register’s ﬂag (i.e., write the index with a 1 in the Index Write bit).

3. Read the settings of the register’s ﬂag.

4. Restore the index ﬁeld by writing back the value of the index ﬁeld stored in step 1.

Core-Controlled Access Protection Flags. For core-controlled host access protection there is a read protect and write pro-

tect bit for each block The core block number are parallel to the host blocks for blocks 2-31. The core-controlled host access

protection has a finer granularity for the first two host blocks, which are split into 16 core blocks, indicated as LA0 - LA15.

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The block number may be calculated using the following equation:

Core_Block_Number = (CR_Space_Address < 128K) ?

CR_Space_Address[20-0] / 64K : CR_Space_Address[20-0] / 8K

The Shared Memory Core Override Read Protect 0-2 registers and Shared Memory Core Override Write Protect 0-2 regis-

ters provide core access to the read and write protect bits, respectively. Bits in these registers may be set and cleared by

writing to the registers.

Response to a Restricted Access

A restricted access is an access that complies with at least one of the following conditions:

●The access type (i.e., Read or Write) of the translated host address (i.e., core address) is protected.

●A reset to the core domain due to a Warm reset event or a ﬂash empty indication is set (Core Boot Block ﬁeld of the

protection word is 11112).

The PC87591x responds to a restricted access by generating an interrupt (if enabled by HERRIEN bit in SMCCST register)

to the core. Two status bits (HWERR and HRERR) indicate whether the restricted access is a read or write access. The

response on the host bus is according to the HERES field.

Forrestrictedwrite accesses: Data written is ignored; when the HERES field is 102, the read or write transactionis completed

with an error SYNC; otherwise, it is completed with a ready SYNC.

For restricted read accesses: When the HERES field is 002, the read or write transaction drives Long Wait (endlessly, unless the

access becomes unrestricted or the HERES field is changed). When the field is 012, the PC87591x completes the transaction

with a ready SYNC and data of 0016; when the field is 102, it completes the transaction with an error SYNC and data of 0016.

Figure 102. Protection Blocks for Protection Bits and Override Protection Bits

Area Not Accessible

to Host

00 0000

01 0000

02 0000

03 0000

0F 0000

10 0000

11 0000

12 0000

1F 0000

1F FFFF

Address in

Core Address

Space

64K

04 0000

00 E000

64K

Host Block

Index Core Override

LA 0

LA 1

LA 2

LA 6

LA 8

LA 15

MBTA

Block Number

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5.3.6 Random Number Generator (PC87591S)

The PC87591S includes a Random Number Generator unit. Once enabled, this unit can provide up to 800 random bits per

second. The random bits may be read one byte at a time from RNGD register when DVALID bit in RNGCS register is set.

Note that a double buffer scheme is used to improve the performance of bit gathering. The randomization of the data is ver-

ified by compliance with FIPS140-1 specifications.

5.3.7 Signaling Interface

For memory update operations, the host may need to exchange signals (indicating the state) with the core. The Signaling

interface supports this scheme. The scheme is designed mainly for polling-based operations, but it allows the host to inter-

rupt the core.

The signaling hardware includes an 8-bit register that may be read by both host and core. The host may modify bits 0 through

3 of this register; the core may modify bits 4 through 7. A host write to the register sets the Host Semaphore Write (HSEMW)

bit in the Shared Memory Core Control and Status register (SMCCST); if the interrupt enable bit (HSEMIE in SMCCST reg-

ister) is set, the shared memory interrupt to the core is set.

5.3.8 Shared Memory Host Registers

The following set of registers is accessible only by the host. The registers are maintained by VDD.

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

Shared Memory Host Register Map

Offset Mnemonic Register Name Type

0016 SMIMA0 Shared Memory Indirect Memory Address 0 R/W

0116 SMIMA1 Shared Memory Indirect Memory Address 1 R/W

0216 SMIMA2 Shared Memory Indirect Memory Address 2 R/W

0316 SMIMA3 Shared Memory Indirect Memory Address 3 R/W

0416 SMIMD Shared Memory Indirect Memory Data R/W

0516 SMHC Shared Memory Host Control R/W

0616 SMHST Shared Memory Host Status Varies per bit

0716 SMHAP1 Shared Memory Host Access Protect 1 Varies per bit

0816 SMHAP2 Shared Memory Host Access Protect 2 Varies per bit

0C16 SMHSEM Shared Memory Host Semaphore Varies per bit

Figure 103. Signaling Interface

HSEM(3-0)

CSEM(3-0)

Host Side

HSEMW

Writes

Core Side

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Shared Memory Indirect Memory Address Register 0 (SMIMA0)

This register defines the addresses 7-0 for a read or write transaction to the memory.

Location: Offset 0016

Type: R/W

Shared Memory Indirect Memory Address Register 1 (SMIMA1)

This register defines addresses 15-8 for a read or write transaction to the memory.

Location: Offset 0116

Type: R/W

Shared Memory Indirect Memory Address Register 2 (SMIMA2)

This register defines addresses 23-16 for a read or write transaction to the memory.

Location: Offset 0216

Type: R/W

Shared Memory Indirect Memory Address Register 3 (SMIMA3)

This register defines addresses 31-24 for a read or write transaction to the memory.

Location: Offset 0316

Type: R/W

Bit 76543210

Name Indirect Memory Address 7-0

Bit Description

7-0 Indirect Memory Address 7-0.

Bit 76543210

Name Indirect Memory Address 15-8

Bit Description

7-0 Indirect Memory Address 15-8.

Bit 76543210

Name Indirect Memory Address 23-16

Bit Description

7-0 Indirect Memory Address 23-16.

Bit 76543210

Name Indirect Memory Address 31-24

Bit Description

7-0 Indirect Memory Address 31-24.

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Shared Memory Indirect Memory Data Register (SMIMD)

This register defines data bits 7-0 for a read or write transaction to the memory.

Location: Offset 0416

Type: R/W

Shared Memory Host Control Register (SMHC)

This register controls the embedded flash operation modes for host-initiated transactions. The register is cleared (0016)on

Host Domain Hardware reset.

Location: Offset 0516

Type: R/W

Shared Memory Host Status Register (SMHST)

This register provides the embedded flash status for host initiated transactions. The register is cleared (0016) on Host Do-

main Hardware reset.

Location: Offset 0616

Type: Varies per bit

Bit 76543210

Name Indirect Memory Data 7-0

Bit Description

7-0 Indirect Memory Data 7-0.

Bit 76543210

Name Reserved PMER Reserved

Reset 00000000

Bit Description

4-0 Reserved.

5PMER (Page Erase). When the bit is set (1), a valid host write to the embedded flash erases the entire page

pointed to by the write address.

This bit can be altered only when HBUSY bit is cleared (0); otherwise results are undeﬁned.

7-6 Reserved.

Bit 76543210

Name Reserved HDERR FMLFULL HBUSY HPERR HEERR

Reset 00000000

Bit Type Description

0 R/W1C HEERR (Host Erase Error). The bit is set (1) when an error occurs during a host-initiated erase. The

bit is cleared by writing 1 to it.

This bit can be cleared only when HBUSY bit is cleared (0).

1 R/W1C HPERR (Host Program Error). The bit is set (1) when an error occurs during a host-initiated program.

The bit is cleared by writing 1 to it.

This bit can be cleared only when HBUSY bit is cleared (0).

2ROHBUSY (Host Busy). Read only. The bit is set (1) when the embedded ﬂash is busy programing or

erasing the flash due to a host-initiated operation.

3ROFMLFULL (Double Buffer Full). Read only. The bit is set (1) when the double buffer is full.

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Shared Memory Host Access Protect Register 1 and 2 (SMHAP1-2)

This register holds the read/write protection and lock control from the host side to the shared memory. The memory is par-

titioned into 64 Kbyte blocks. SMHAP1 controls the first 16 blocks (addresses 0-1 Mbyte). SMHAP2 controls the second

group of 16 blocks (addresses 1-2 Mbyte). The block mapping is in the core address space. See “Setting the Host Access

Protection Flags” on page 301 for the calculation method of the block address in the host address space. On Host Domain

Hardware reset, all write-protect flags are set and all lock-protect and read-protect flags are cleared.

Location: Offset 0716 and 0816

Type: Varies per bit

Shared Memory Host Semaphore Register (SMHSEM)

This register provides eight semaphore bits between the core and host. Four of the bits may be set by the host and four may

be set by the core. The register is cleared (0016) on Host Domain Hardware reset.

Location: Offset 0C16

Type: Varies per bit

4 R/W1C HDERR (Host Data Loss Error). The bit is set (1) when a write to a full buffer is detected. The bit is

cleared by writing 1 to it.

This bit can be cleared only when HBUSY bit is cleared (0).

7-5 Reserved.

Bit 76543210

Name Host Access Protection Index Index Write Host Lock

Protection Host Write

Protection Host Read

Protection

Reset 0 0 0 0 0 0 1 0

Bit Type Description

0 R/W Host Read Protection. The block number is as held in the index field (bits 7-4). Note that the Core

Override protection may disable reads even when reads are allowed by this register.

0: Host Reads are allowed for this block

1: Host Reads are inhibited for this block

1 R/W Host Write Protection. The block number is as held in the index field (bits 7-4). Note that the Core

Override protection may disable writes even when writes are allowed by this register.

0: Program and erase are allowed for this block

1: Program and erase are inhibited for this block

2 R/W Host Lock Protection. The block number is as held in the index field (bits 7-4). When set, the bit

prevents changing the values of the Host Read Protect, Host Write Protect and Host Lock Protection

bits for this block. Once set, this bit is cleared by Host Domain Hardware reset only.

0: Changes to protection bits (0-2) for this block are enabled

1: Protection bits (0-2) for this block are locked, and the bits’ values may not be changed

3WOIndex Write. Indicates that this is an index write transaction; therefore, bits 0-2 of this register are

ignored. When read, always returns 0.

0: Write transaction affects all fields of this register (writes to bits 0-2 use the newly written index)

1: Write transaction for purpose of index update; bits 0-2 should not be updated by this write.

7-4 R/W Host Access Protection Index. Holds the index number of the host block accessed by the other fields

in this register. All blocks are 64 Kbytes. The block index is calculated in the core address space. For

details of the address conversion, see Section 5.3.2 on page 297.

Index = Block_First_Address / 64K

In SMHAP1: 0000-111116 for indexes 0-15, respectively

In SMHAP2: 0000-111116 for indexes 16-31, respectively

Bit Type Description

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5.3.9 Shared Memory Core Registers

The following set of registers is accessible only by the core. These registers are maintained by VCC.

For a summary of the abbreviations used for Register Type, see Section 2 on page 34.

Shared Memory Core Register Map

Shared Memory Core Control and Status Register (SMCCST)

This register provides control and status of read/write from/to a restricted address. The register is cleared (0016) on reset.

Location: 00 F90016

Type: R/W

Bit 76543210

Name CSEM3 CSEM2 CSEM1 CSEM0 HSEM3 HSEM2 HSEM1 HSEM0

Reset 0 0 0 0 0 0 0 0

Bit Type Description

3-0 R/W HSEM3-0. Four bits that may be updated by the host and read by both the host and the core.

7-4 RO CSEM3-0. Four bits that may be updated by the core and read by both the host and the core.

Mnemonic Register Name Type

SMCCST Shared Memory Core Control and Status R/W

SMCTA Shared Memory Core Top Address RO in IRE and OBD environments;

R/W in DEV environment

SMHSEM Shared Memory Host Semaphores Varies per bit

SMCORP0-2 Shared Memory Core Override Read Protect 0-2 R/W or RO

SMCOWP0-2 Shared Memory Core Override Write Protect 0-2 R/W or RO

RNGCS Random Number Generator Control and Status Varies per bit

RNGD Random Number Generator Data RO

Bit 76543210

Name HSEMIE HSEMW HLOCK HERES HERRIEN HWERR HRERR

Reset 0 0 0 0 0000

Bit Description

0HRERR (Host Read Error). The bit is set (1) when the host attempts to read from a read-protected block or

out-of-range address. An out-of-range address is an address that the LPC conﬁguration module deﬁnes as

mapped to the PC87591x, but it is actually translated to a reserved address in the core address space. Writing

1 to this bit clears it to 0. Writing 0 has no effect.

1HWERR (Host Write Error). The bit is set (1) when the host attempts to write to a read-protected block or out-

of-range address. An out-of-range address is an address that the LPC conﬁguration module deﬁnes as mapped

to the PC87591x, but it is actually translated to a reserved address in the core address space. Writing 1 to this

bit clears it to 0. Writing 0 has no effect.

2HERRIEN (Host Error Interrupt Enable). When set (1) and either the HRERR or HWERR bit is set (1), a core

interrupt is generated; otherwise, the core interrupt is inactive.

Host Controller Interface Modules (Continued)

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Shared Memory Core Top Address Register (SMCTA)

This register provides information about the size of the on-chip main block. The register is loaded with its default value on

VCC Power-Up reset only.

Location: 00 F90216

Type: RO in IRE and OBD environments

R/W in DEV environment

Shared Memory Host Semaphore Register (SMHSEM)

This register provides eight semaphore bits between the core and the host. Four of the bits may be set by the host; four may

be set by the core. The register is cleared (0016) on reset.

Location: 00 F90416

Type: Varies per bit

4-3 HERES (Host Error Response). Controls response type on read/write from/to a protected block or out-of-range

address. An out-of-range address is an address that the LPC conﬁguration module deﬁnes as mapped to the

PC87591x, but it is actually translated to a reserved address in the core address space.

Bits

4 3 Description

0 0: Drive Long Wait for read; ignore write

0 1: Read back 0016; ignore write

1 0: Drive error SYNC for both read and write

1 1: Reserved

5HLOCK (Host Lock).

0: The bridge does not generate write transactions on the core bus

1: The bridge can generate write transactions on the core bus

This bit should be set only when FMBUSY bit is cleared (see ”Flash Memory Status Register (FLSR)” in

Section 4.16.7 on page 228).

6HSEMW (Host Semaphore Write). The bit is set (1) when the host writes to HSEM register. Writing 1 to this

bit position clears it to 0. Writing 0 has no effect.

7HSEMIE (Host Semaphore Interrupt Enable). When the bit is set (1), the interrupt to the core is set (level

high) if HSEMW is set.

Bit 76543210

Name Reserved MBSD

Reset 0 0 0 2 (see note in ﬁeld description)

Bit Description

4-0 MBSD (Main Block Size Deﬁnition). Defines the size of the main block in 64 Kbyte units. Thus the MBTA value

is MBSD * 1 000016. Note that MBTA is actually the ﬁrst address beyond the main block.

The reset value of this ﬁeld is affected by the Force MBTA Zero bit in the protection word (see Section 4.16.6 on

page 226). When the Force MBTA Zero bit is set, the reset value of this ﬁeld is 016; when the bit is cleared, the

reset value is as shown in the bit table, above.

This ﬁeld is loaded on VCC Power-Up reset with the on-chip ﬂash size. In DEV environment, the MBSD may be

loaded with a new value.

7-5 Reserved.

Bit 76543210

Name CSEM3 CSEM2 CSEM1 CSEM0 HSEM3 HSEM2 HSEM1 HSEM1

Reset 0 0 0 0 0 0 0 0

Bit Description

Host Controller Interface Modules (Continued)

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Shared Memory Core Override Read Protect Registers 0-2 (SMCORP0-2)

SMCORP0-2 are 16-bit registers that provide core override on the host read protection bits. For the host to be able to read

a memory location, both the Host Read Protection bit (controlled through the Shared Memory Host Access Protect Register

1 or 2) and the associated bit in SMCORP0-2 should be cleared. Each bit in this register is associated with a memory block,

as described in the bits description. Bits in these registers may be RO or RW depending on their position and the size of the

core and host boot blocks. SMCORP0-2 registers are loaded with reset values either on reset or when the value of the

SMCTA register is changed; the reset values depend on the size of the core and host boot blocks, as defined in the protec-

tion word.

Location: 00 F91016, 00 F91216, 00 F91416

Type: R/W or RO as described in the description below

Bit Type Description

3-0 RO HSEM3-0. Four bits that may be updated by the host and read by both the host and the core.

7-4 R/W CSEM3-0. Four bits that may be updated by the core and read by both the host and the core.

Bit 1514131211109876543210

Name ORPLA15-0

Reset See bit description below 1 See bit description below

Bit 1514131211109876543210

Name ORP15-2 Reserved

Reset See bit description below 0 0

Bit 1514131211109876543210

Name ORP 31-16

Reset See bit description below

Bit Description

15-0 ORPLA15-0 (Override Read Protect Low Addresses 15 through 0).

ORP15-2 (Override Read Protect 15 through 2).

ORP31-16 (Override Read Protect 15 through 0).

Each bit affects the host’s ability to read from one block. On the low addresses (covered by ORPLAi), the block

size is 8 Kbytes. For the other blocks it is 64 Kbytes. The block address is calculated as follows:

Low address blocks, ORPLAi: from i*8K to (i+1)*8K−1

Other blocks, ORPLj: from j*64K to (j+1)*64K

See Figure 102 on page 302 for a description of the block mapping. Bit 7 (ORPLA7) in SMCORP0 register is

read only.

0: Do not override the host read protect setting for the block

1: Host read for this block is disabled regardless of the setting of the respective bit in the host register

The reset values of these registers are as follows:

Core boot blocks that cover address 00 000016 to CR_Boot_Block_Size: 1

Host boot blocks not in above group and from (MBTA1−Host_Boot_Block_Size) to MBTA: 0

All other blocks: 1

The following access limitations apply to the register bits:

Core boot blocks that cover address 00 000016 to CR_Boot_Block_Size: RO

Host boot blocks not in above group and ranging from (MBTA1−Host_Boot_Block_Size) to MBTA:RO

All other blocks: RW

1. Use the MBTA as speciﬁed in SMCTA register, without the MBTA override in the protection word.

Host Controller Interface Modules (Continued)

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Shared Memory Core Override Write Protect Registers 0-2 (SMCOWP0-2)

SMCOWP0-2 are 16-bit registers that provide override on the host write protection bits. For the host to be able to write a

memory location, both the Host Write Protection bit (controlled through the Shared Memory Host Access Protect Register 1

or 2) and the associated bit in SMCOWP0-2 should be cleared. Each bit in this register is associated with a memory block,

as described in the bit description. Bits in these registers may be RO or RW depending on their position and the size of the

core and host boot blocks. These registers are cleared on reset and change in value of SMCTA.

Location: 00 F92016, 00 F92216, 00 F92416

Type: R/W

Bit 1514131211109876543210

Name OWPLA15-0

Reset FFFF16

Bit 1514131211109876543210

Name OWP15-2 Reserved

Reset FFFF16

Bit 1514131211109876543210

Name OWP 31-16

Reset FFFF16

Bit Description

15-0 OWPLA15-0(Override Write Protect Low Addresses 15 through 0).

OWP15-2(Override Write Protect 15 through 2).

OWP31-16(Override Write Protect 15 through 0).

Each bit affects the host’s ability to write to one block. On the low addresses (covered by OWPLAi), the block

size is 8 Kbytes. For the other blocks it is 64 Kbytes. The block address is calculated as follows:

Low Address Blocks, OWPLAi: from i*8K to (i+1)*8K−1

Other Blocks, OWPLj: from j*64K to (j+1)*64K

See Figure 102 on page 302 for a description of the block mapping. Bit 7 (OWPLA7) in SMCOWP0 register is

read only.

0: Do not override the host Write Protect setting for the block

1: Host writes for this block are disabled regardless of the setting of the respective bit in the host register

The following access limitations apply to the register’s bits:

Core boot blocks that cover address 00 000016 to CR_Boot_Block_Size: RO

Host boot blocks not in above group and ranging from (MBTA1−Host_Boot_Block_Size) to MBTA:RO

All other blocks: RW

1. Use the MBTA as speciﬁed in SMCTA register, without the MBTA override in the protection word.

Host Controller Interface Modules (Continued)

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Random Number Generator Control/Status Register, RNGCS (PC87591S)

This register controls the Random Number Generator (RNG) unit. It also provides status of its operation and the validity of

the numbers at its output. The register is cleared on reset.

Location: 00 F93016

Type: Varies per bit

Bit 76543210

Name Reserved CLKP DVALID RNGE

Reset 0 0 0 0 0000

Bit Type Description

0 R/W RNGE (Random Number Generator Enable). Enables the operation of the RNG. This bit should be

cleared to reduce power consumption when the RNG is not required. Some wake-up time may apply

before the ﬁrst number is generated after RNG activation.

0: RNG disabled (default)

1: RNG enabled

1RODVALID (Data Valid). Indicates that valid data may be read from RNGD register.

0: Data not valid; RNGD always reads 0016 (default)

1: Data valid; a random number is read

4-2 R/W CLKP (Clock Pre-Scaler). Defines the pre-scale ratio between the RNG internal clocks and the core

clock. To change the CLP contents: (a) Clear RNGE; (b) Change CLKP (c); Set RNGE to re-enable the

RNG. CLKP may be set to a value above the actual clock frequency of the core, but it should not be

set to a lower value than the CLK frequency.

Bits

4 3 2 Description

0 0 0: 15-20 MHz (default)

0 0 1: 12-15 MHz

0 1 0: 9-12 MHz

0 1 1: 7-9 MHz

1 0 0: 6-7 MHz

1 0 1: 5-6 MHz

1 1 0: 4-5 MHz

1 1 1: 3-4 MHz

7-5 Reserved.

Host Controller Interface Modules (Continued)

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Random Number Generator Data Register, RNGD (PC87591S)

This register provides the random number value of the RNG.

Location: 00 F93216

Type: RO

5.3.10 Usage Hints

●After clearing (0) HLOCK bit, the core ﬁrmware should wait until FMBUSY bit is clear (0) before it accesses the on-

chip ﬂash (see ”Flash Memory Status Register (FLSR)” in Section 4.16.7 on page 228).

●Enable Access to the shared memory: Before any access may occur, the shared memory access must be enabled

using the SIO Conﬁguration registers (see Section 6.1.11 on page 349). To enable shared memory as a boot device,

the SHBM strap should be set appropriately (see Section 2.2.11 on page 50).

●Host boot block may be implemented as part of the on-chip ﬂash or in the external memory. In the latter case, access

to the Host boot block must be enabled by the core after the memory access conﬁguration is completed.

●For host shared memory read:

1. Have host enable the memory for reading (if disabled), using SMHAP1 and SMHAP2 registers.

2. Have core enable the memory for reading (in most cases, disabled by default), using SMCORP0-2 registers.

3. Read from the designated address location.

●For host shared memory write or erase:

1. Have host enable the desired location for write, using SMHAP1 and SMHAP2 registers (note that the memory

may be disabled for reads if the hardware validation is in use).

2. Have core enable the desired location for a write, using SMCOWP0-2 registers.

3. Enable the host write operations by setting HLOCK bit in SMCCST register.

4. To perform a page erase operation, the host should set PMER bit in SMHC register and write any data to

an address in the page. The page is erased when HBUSY bit in SMHST register is cleared, and an erase

error, if it occurs, is ﬂagged by HEERR bit in SMHST register.

5. To program a byte in the on-chip ﬂash, the host should make sure PMER bit in SMHC register is clear

and write the required data to the designated address location. The programing is completed when HBUSY bit

in SMHST register is cleared. At this time, an erase error, if it occurs, is ﬂagged by HPERR in SMHST register.

6. Programing the expansion memory is done using read/write operations to addresses associated with that memory.

The transactions are passed to the memory through the core bus and BIU modules. The software should perform

the appropriate sequence of read and write operations as required by the ﬂash device in use.

●At different stages of the ﬂash programing by the host, communication between the core and host is required. Various

mechanisms may be used for this, one of which is the Shared Memory Semaphore mechanism. This mechanism is

tuned for host-initiated operations that use polling on the registers. The core may receive an interrupt or use polling

to identify a semaphore change. An example of bit allocation is:

Bit 0 - Host requests control of ﬂash

Bit 4 - Core grants control to host

The sequence is:

1. Host sets bit 0 to request control of bus.

2. Core identiﬁes that bit 0 is set and does the required operations, including setting HLOCK bit in

SMCCST register to enable host access.

3. Core sets bit 4, indicating to the host that memory access is granted.

4. Host performs write/erase to the memory, as required.

5. Host clears bit 0, indicating completion of the process.

6. Core clears HLOCK and protects the memory.

7. Core indicates completion of process by clearing bit 4.

Bit 76543210

Name RNGD7-0

Bit Description

7-0 RNGD0-7 (Random Number Generator Data Bits). Provides random data output from the RNG module. When

DVALID in RNGCS register is cleared, RNGD register always reads 0016. When DVALID in RNGCS register is

set, the data read is a random number. Any random number can be read only once, after which it is marked as

invalid and replaced by a new number.

Host Controller Interface Modules (Continued)

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5.4 CORE ACCESS TO HOST-CONTROLLED MODULES

The PC87591x enables the core to access the Host-Controlled module registers (e.g., host configuration module, RTC and

MSWC), using the SuperI/O Internal Bus (SIB) controller.

Host-Controlled Modules Register Arbitration. SincethehostprocessorsoftwareandthePC87591xfirmwarecannotac-

cess a Host-Controlled module simultaneously, they must communicate to prevent conflicts in Host-Controlled module reg-

ister usage.

Access to the Host-Controlled modules is controlled via a lock bit for each module. When the relevant lock bit is cleared,

access to the Host-Controlled modules registers by the host processor is enabled. When the relevant lock bit is set, access

to the Host-Controlled module registers by the host processor is blocked (i.e., write operations are ignored and read opera-

tions return 0016). Any attempt by the host to access the locked register is flagged by setting the respective bit in SIOLV

SIB Arbitration. The host and core should access the Host-Controlled modules only after preventing host access to the

module (using lock bits, as explained in the previous paragraph). The SIB controller arbitrates SIB usage between the host

and core. If a core transaction starts after an LPC transaction has started, it waits for the completion of the LPC transaction.

If a core transaction starts before an LPC transaction starts, the core transaction finishes before handling the LPC transac-

tion.

The PC87591x firmware may access the Host-Controlled modules only while the core domain is in Active mode, the Host

Domain power plane is on and the host domain clock is enabled with a minimum operation frequency of TBD.

Core Read Operation. To perform a read operation by the core from a Host-Controlled module register:

1. Set CSAE bit in SIBCTRL register, if not already set.

2. Verify that both CSRD and CSWR bits in SIBCTRL register are cleared.

3. Select the device to be accessed by setting its respective bit in CRSMAE register, if not already set. All other bits in the

4. Specify the offset of the register in the device in IHIOA register, if not already specified.

5. Write 1 to CSRD bit in SIBCTRL register.

6. Read the CSRD bit in SIBCTRL until it returns 0.

7. Read the data from IHD register.

Core Write Operation. To perform a write operation by the core from a Host-Controlled module register:

1. Set CSAE bit in SIBCTRL register, if not already set.

2. Verify that both CSRD and CSWR bits in SIBCTRL register are cleared.

3. Select the device to be accessed by setting its respective bit in CRSMAE register, if not already set. All other bits in the

4. Specify the offset of the register in the device in IHIOA register, if not already specified.

5. Write the data to IHD register; this starts the write operation to the device.

6. Read the CSWR bit in SIBCTRL until it returns 0; this indicates the completion of the write transaction.

The following sequence is provided for minimal conflict between host and core in the use of Host-Controlled peripherals.

1. After arbitrating the use of the specific Host-Controlled modules with the host, set the corresponding lock bit (see

LKSIOHA register).

2. Read and save all Host-Controlled module registers required for proper operation of the host. Beware of destructive

reads.

3. After the Host-Controlled module access is complete, restore the Host-Controlled module registers saved in step 2.

4. Clear the corresponding lock bit to allow the host to access the Host-Controlled module.

When accessing the RTC, also:

1. To access locked memory locations in the RTC, set (1) RTCMR bit in SIBCTRL register to clear the RTC lock bits.

2. Access the RTC’s CMOS-RAM and its registers. To prevent conflicts with the host software, the firmware should not read

any of the RTC read-volatile registers.

3. After the RTC access is complete, if the RTC locking was removed, re-lock the RTC memory and restore the RTC mem-

ory bank selection and the address pointer.

Host Controller Interface Modules (Continued)

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5.4.1 Core Access to Host-Controlled Module Registers

The following set of registers is accessible only by the core. The registers are powered by VCC.

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

Core Access to Host-Controlled Modules Register Map

Indirect Host I/O Address Register (IHIOA)

This register defines the host I/O address for read or write transactions from/to the Host-Controlled modules. The I/O ad-

dress is an offset from the least significant bits of the device address. The accessed device is selected using the Core to

SIB Modules Access Enable Register (CRSMAE); see page 316.

Location: 00 FCE016

Type: R/W

Indirect Host Data Register (IHD)

This register holds host data for read or write transactions from/to the Host-Controlled modules.

Location: 00 FCE216

Type: R/W

Mnemonic Register Name Type

IHIOA Indirect Host I/O Address R/W

IHD Indirect Host Data R/W

LKSIOHA Lock SuperI/O Host Access R/W

SIOLV SuperI/O Access Lock Violation R/W1C

CRSMAE Core to SIB Modules Access Enable R/W

SIBCTRL SIB Control Varies per bit

Bit 1514131211109876543210

Name Reserved Indirect Host I/O Offset

Reset 0 000000000000000

Bit Description

7-0 Indirect Host I/O Offset. Only offsets within the device range are allowed. Other offsets may have unpredictable

results.

15-8 Reserved.

Bit 76543210

Name Indirect Host Data

Reset 00000000

Bit Description

7-0 Indirect Host Data.

Host Controller Interface Modules (Continued)

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Lock SuperI/O Host Access Register (LKSIOHA)

This register controls locking of host access to the Host-Controlled modules. All bits of this register, except bit 1, are cleared

on reset. The bit 1 reset value is defined by RTC Lock Default bit in “Protection Word” on page 226.

Location: 00 FCE416

Type: R/W

SuperI/O Access Lock Violation Register (SIOLV)

This register provides an error indication when a host lock violation occurs on Host-Controlled modules access.

Location: 00 FCE616

Type: R/W1C

Bit 76543210

Name Reserved LKRTCHA LKCFG

Reset 000000seetext0

Bit 15 14 13 12 11 10 9 8

Name Reserved

Reset 00000000

Bit Description

0LKCFG (Lock Conﬁguration Registers Host Access).

0: Host processor access to the Configuration registers is enabled

1: Host processor access to the Configuration registers is blocked

1LKRTCHA (Lock Real-Time Clock (RTC) Host Access).

0: Host processor access to the RTC registers is enabled

1: Host processor access to the RTC registers is blocked

15-2 Reserved.

Bit 76543210

Name Reserved RTCLV CFGLV

Reset 00000000

Bit 15 14 13 12 11 10 9 8

Name Reserved

Reset 00000000

Bit Description

0CFGLV (Conﬁguration Register Lock Violation). The bit is set (1) when the host processor attempts to access

the conﬁguration registers while LKFDCHA bit in LKSIOHA register is set.

1RTCLV (Real-Time Clock (RTC) Lock Violation). The bit is set (1) when the host processor attempts to access

the RTC while LKRTCHA bit in LKSIOHA register is set.

15-2 Reserved.

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Core to SIB Modules Access Enable Register (CRSMAE)

This register enables core access to the Host-Controlled modules. Only one of the bits in this register may be set at a time.

Location: 00 FCE816

Type: R/W

Bit 76543210

Name Reserved RTCAE CFGAE

Reset 00000000

Bit 15 14 13 12 11 10 9 8

Name Reserved MSWCAE

Reset 00000000

Bit Description

0CFGAE (Conﬁguration Register Core Access Enable).

0: Core access to the Configuration registers is disabled

1: Core access to the Configuration registers is enabled

1RTCAE (Real-Time Clock (RTC) Core Access Enable). The RTC has two chip-select signals deﬁned in its

conﬁguration space, each with two registers. A1 of the offset is used to differentiate between the two (when A1

is 0, the pair pointed to by index 60, 61 is accessed; when A1 is 1, the pair pointed to by index 62, 63 is

accessed).

0: Core access to the RTC registers is disabled

1: Core access to the RTC registers is enabled

7-2 Reserved.

8MSWCAE (Mobile System Wake-Up Control (MSWC) Access Enable).

0: Core access to the MSWC registers is disabled

1: Core access to the MSWC registers is enabled

15-9 Reserved.

Host Controller Interface Modules (Continued)

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SIB Control Register (SIBCTRL)

This register allows the core to control the SIB controller operation.

Location: 00 FCEA16

Type: Varies per bit

Bit 76543210

Name Reserved RTCMR CSWR CSRD CSAE

Reset 00000000

Bit Type Description

0 R/W CSAE (Core to SIB Access Enabled).

0: Core access to the SIB bus is disabled (default)

1: Core access to the SIB bus is enabled. The device to be accessed is selected by the SIB Device Select

1 R/W1S CSRD (Core Read from SIB). Writing 1 to this bit starts a read from the SIB; the read is based on the

address and enabled device speciﬁed in CRSMAE register. A write of 0 to this bit is ignored. This bit

is cleared when the read operation is completed, indicating that the data is ready in IHD register.

2ROCSWR (Core Write to SIB). The bit is set by a write operation to IHD register. It is cleared when the

write to the SIB is completed.

3 R/W1S RTCMR (Real-Time Clock (RTC) Master Reset). Writing 1 to this bit generates a reset pulse to the

RTC module. This bit is cleared by the hardware once the reset pulse is completed. Writing 0 to this

bit is ignored.

7-4 Reserved.

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5.5 MOBILE SYSTEM WAKE-UP CONTROL (MSWC)

The MSWC detects and handles wake-up events from various sources in the host-controlled modules. The MSWC gener-

ates interrupts to the host via SMI or PWUREQ, and/or alerts the core, which enables the core to control the wake-up se-

quence. Since the MSWC is powered by VCC, it can operate in low power consumption states. Some MSWC operations

depend on the presence of a clock; these functions are not available when the core clock is turned off.

Figure 104 shows the block diagram of the MSWC.

5.5.1 Features

The MSWC recognizes the following maskable system events:

●Modem ring (RI1 and RI2 pins)

●Telephone ring (RING input pin)

●Wake-up on module IRQs for RTC, KBD and Mouse

●Software events

—Software triggered wake-up event

—ACPI power state change indications

—Software off command

The MSWC notifies the host and/or core when any of the above events occur by asserting one or more of the following output

pins:

●Power-Up Request (PWUREQ)

●System Management Interrupt (SMI)

●Interrupt to the host (IRQ)

●MSWC interrupt to the core

5.5.2 Wake-Up Event Detection and Status Bits

The MSWC monitors various system signals for a wake-up event. When an event is detected, a status bit is set to record it.

Each event goes to the Wake-Up Mode Control Logic, which determines its effect (see Figure 105 for an illustration of this

mechanism). A set of dedicated registers is used to determine the wake-up criteria, including the RING detection mode.

Figure 104. MSWC Block Diagram

Core Peripheral Bus

Host Domain Internal Bus

Wake-Up

Configuration

RI1 RI2

Modules’ IRQs

RING Input

SMI

PWUREQ

Status Registers

Configuration

Registers

Off Event

RTC Alarm

SMI

MSWC Interrupt

Control &

Wake-Up

Event

Detection IRQ

PM I/F

Channels

Host Controller Interface Modules (Continued)

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The following wake-up input events are detected by the MSWC:

●Software events

●IRQ from SuperI/O modules

●Modem Ring (RI1 and RI2)

●Telephone Ring (RING input)

●ACPI state change

●Legacy off event

●RTC Alarm

When an input event is detected, the corresponding status bit in both host and core status registers is set to 1, regardless

of any Routing Enable bit setting. If both the status bit and a Routing Enable bit corresponding to a specific event are set to

1 (no matter in what order), the output pin corresponding to that Routing Enable bit is asserted.

A status bit is cleared by writing 1 to it. Writing 0 to a status bit does not change its value. Clearing the routing enable bit of

an event prevents it from issuing the corresponding system notification (output event) but does not affect the status bit.

Figure 105 shows the routing scheme of detected wake-up events to the various means of system notification (i.e., output

events).

Both the core and the host have status registers; thus both core and host software can monitor the various event status bits.

This enables handling of events via wake-up logic that is implemented as part of the Embedded Controller firmware, and

passing the wake-up notifications through the Power Management host-interface protocol. The core uses a mask register

(WK_SMIENn) to define which of the status bits it should respond to.

It is recommended that each of the wake-up sources be handled by one handler routine on the host (i.e., SMI, SCI or IRQ

triggered) or the core.

Software Event

A software event may be used to trigger a wake-up event via software control. A software event to the host is active when

the Software Event Status bit in WK_STS0 register is set. A software event to the core is active when the Software Event

Status bit in MSHES0 register is set.

The software event may be activated (i.e., the status bits in WK_STS0 and MSHESO registers are set) by writing 1 to the

Software Event Status bit in WK_STS0 register when the bit is cleared. Once this bit is set to 1, writing 1 to the bit clears it.

WK_STS0 is accessible by the host only when VDD is present. The software event can be activated by the host only when

VDD is present. The software event may be activated by the core by the core access to the Host-Controlled Module bridge

even when VDD is off.

When HSECM bit in MSWCTL1 register is cleared, the Software Event Status bit in MSHES0 is set on a change of the re-

spective bit in WK_STS0 register from 0 to 1. When HSECM bit is set, the Software Event Status bit in MSHES0 is set on a

write of a 1 to the respective bit in WK_STS0. The Software Event Status bit in MSHES0 is cleared by writing 1 to it.

Module IRQ Wake-Up Event

A module IRQ wake-up event is defined as the leading edge of the IRQ assertion of the RTC.

To enable the IRQ of a specific logical device to trigger a wake-up event, the associated enable bit must be set to 1. This is

bit 4 of the Interrupt Number and Wake-Up on IRQ Enable register, located at index 7016 in the configuration space of the

logical device (see Table 52 on page 339). When this bit is set, any IRQ assertion of the corresponding logical device acti-

vates the module IRQ wake-up event. Therefore, the module IRQ wake-up event is a combination of all IRQ signals of the

logical devices for which wake-up on IRQ is enabled.

When the event is detected as active, its associated status bit (bit 7 of WK0_STS register) is set to 1. If the associated enable

bit (bit 7 of WK_EN0 register) is also set to 1, the PWUREQ output is asserted and remains asserted until the status bit is

cleared.

Since VDD powers IRQ generation of the logical devices, a module IRQ event can be activated only when VDD is present

(see Section 6.1 on page 335 for a list of logical devices).

Modem Ring

High to low transitions on RI1 (or RI2) indicate the detection of a ring in an external modem connected to Serial Port 1 (or

Serial Port 2) and can be used as wake-up events.

Telephone Ring

A telephone ring is detected by the MSWC by processing the raw signal coming directly from the telephone line into the

RING input pin. Detection of a pulse train, with a frequency higher than 16 Hz lasting at least 0.19 sec, is used as a wake-

up event.

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The RING pulse-train detection is achieved by monitoring the falling edges on RING in time slots of 62.5 msec (a 16 Hz

cycle). A positive detection occurs if falling edges of RING are detected in three consecutive time slots, following a time slot

in which no RING falling edge is detected. This detection method guarantees the detection of a RING pulse train with fre-

quencies higher than 16 Hz. It ﬁlters out (does not detect) pulses of less than 10 Hz and may detect pulses between 10 Hz

and 16 Hz.

ACPI State Change and Legacy Off Events

The host may operate in either Legacy or ACPI mode. The operation mode is specified by the Power Button Mode bit in

SuperI/O Configuration D register (SIOCFD). When EICFGPBM bit in MSIEN2 register is set, a change to the Power Button

Mode bit generates an interrupt to the core. The core may read the value of the Power Button Mode bit, using CFGPBM bit

in MSWCTL2 register, to determine how to interpret the other power state request bits.

The Power Supply Off bit in SIOCFD register may be used in Legacy mode to indicate a request to turn power off. A write

of 1 to this bit sets CFGPSO bit in MSWCTL2 register; then, if EICFGPSO bit in MSIEN2 register is set, an interrupt to the

core is generated, indicating the event.

A set of System State Change Request bits (S1-S5) are provided in WK_STATE register. The host uses these bits for ACPI-

compliant state change requests. A write of 1 to any of these bits indicates a state change request to the core through the

respective bit in MSWCTL2 register. When all bits in WK_STATE are written with 0, a request of S0 is indicated, and ACPIS0

bit in MSWCTL2 register is set. When any S0-S5 bit in MSWCTL2 is set and the respective mask bit in MSIEN2 register is

set, an interrupt to the core is generated whenever a change to any of the state bits is detected.

All interrupt requests may be cleared by writing 1 to the corresponding status bit or by masking the event (by clearing the

corresponding Interrupt Enable bit).

RTC Alarm

The RTC module may generate an ALARM signal (see Section 6.2.8 on page 359). The RTC alarm can serve as a wake-

up request to wake up the system; the request is routed to the core, which then wakes up the system. To enable an alarm

wake-up, the following settings should be made:

●Set the Alarm conditions in the RTC module. By masking the various interrupts, software may select a wake-up either

to the host directly, using the RTC’s IRQ, or to the core through the Alarm signal.

●Enable the Wake-Up on Alarm status interrupt masking (optional, for Interrupt Enabled mode) by setting EIRTCAL bit

in MSIEN2 register.

●Verify that the RTCAL bit in MSWCTL3 bit is cleared (no pending Alarm request).

●Enable the Wake-Up on MSWC event in the MIWU and ICU modules.

●Verify that the ALARM bit in the RTC is cleared.

After an ALARM event is detected in the RTC, the RTC ALARM status bit is set (bit 5 in CRC register, page 369); in re-

sponse, RTCAL bit in MSWCTL3 register is set.

When handling an ALARM event, make sure that no events are lost by clearing RTCAL bit before clearing the ALARM status

in the RTC.

5.5.3 Wake-Up Output Events

The MSWC generates four types of output events:

●IRQ - an interrupt routed as conﬁgured in the MSWC PnP conﬁguration registers.

●PWUREQ - an event that is typically routed to an input in the chipset that triggers an SCI event.

●SMI - an event typically connected to an input in the chipset that triggers an SMI event.

●MSWCI - an interrupt to the MIWU module in the core domain. This enables the core ﬁrmware to handle the wake-

up events.

Figure 105 illustrates the enabling mechanism and the event generation scheme for the various output events. Output

events to the host are generated for input events that have their status bit set (WK_STSn.i is 1). Output events to the core,

through the MIWU, are generated for input events that have their core status bit set (MSHESn.ii is 1).

Each of the three Host Wake-Up Event Routing Control registers (WK_ENn, WK_SMIENn and WK_IRQENn) holds a Rout-

ing Enable bit for each event; this allows selective routing of these events to PWUREQ, SMI and/or the assigned MSWC

interrupt request (IRQ) channel, respectively.

After an output event is asserted, it is active until all set status bits are cleared or masked. The current status of the event

may be read at the ACPI status registers in the chipset’s ACPI controller or by reading “Wake-Up Event Status Register 0

(WK_STS0)” on page 323 and “Wake-Up Signals Value Register (WK_SIGV)” on page 325.

As shown in Figure 106, for SMI output events, the MSWC combines the event request coming from the Host Interface’s

Power Management channels 1 and 2 with MSWC internal SMI events; for PWUREQ output events, the MSWC combines

the PWUREQ events generated in the MSWC module with wake-up requests associated with the IRQ configuration regis-

ters.

Host Controller Interface Modules (Continued)

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The SMI may be output from the PC87591x using the dedicated SMI signal or by routing SMI to an interrupt request channel

via the device’s configuration registers.

The Wake-Up Event Routing Control register, MSHEIEn, which is controlled by the core, holds an enable bit for each of the

events, which allows selective routing of these events to the core wake-up interrupt (MSWCI) to the MIWU. The core event

is controlled using a separate set of status signals to prevent race conditions when clearing events.

The MSWCI interrupt is a level high interrupt that gathers requests from MSHESn, MSWCTL2 and MSWCTL3 registers.

Once an output event is asserted, it keeps its active state until all set status bits are cleared or masked. This interrupt signal

is connected to the MSWC wake-up input of the MIWU. This enables handling state change requests even in Idle mode.

The MSWC output for this input is connected to the core through the MIWU module, enabling a power state change on in-

terrupt.

Event i

Detection

WK_SMIENn.i

WK_IRQENn.i

WK_ENn.i

Wake-Up Event i

From Wake-Up

PWUREQ

SMI

IRQ

Event

Routing

Logic

WK_STSn.i

Extension Logic

To Peripheral Bus

MSHEIEn.i MSWCI

to MIWU

MSHESn.i

Figure 105. Wake-Up Event Routing Scheme

Wake-Up

From Host

I/F Module

SMI

Module SMI

PWUREQ

IRQj Wake-Up

PWUREQ Wake-Up Module

Wake-Up IRQi Wake-Up

Figure 106. SMI and PWUREQ Source Gathering Scheme

from IRQs

Routing

PM1SMI

PM2SMI

Host Controller Interface Modules (Continued)

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5.5.4 Other MSWC Controlled Elements

In addition to its Power Management functions, the MSWC controls the handling of the following system control elements:

●Host Conﬁguration Address Selection

●Host Keyboard Reset Fast Reset Output (KBRST)

●GA20 Pin Functionality

●Host Power on indication

Host Conﬁguration Address Selection

The standard strap configuration enables the selection of one of two SuperI/O configuration register addresses. When the

PC87591x is enabled in Programmable Configuration Address mode (see Table 47 on page 335), the core may set the ad-

dress of the SuperI/O configuration index/data registers.

HCFGBAL and HCFGBAH are byte-wide read/write registers. HCFGBAL holds the least significant byte of a host mother-

board PnP initial configuration address; HCFGBAH holds the most significant byte. The contents of HCFGBAH and HCFG-

BAL change only during VCC Power-Up reset.

To update the base address of the SuperI/O configuration index/data registers, do the following:

1. Clear VHCFGA bit in MSWCTL1 register by writing 1 to it.

2. Write the lower byte of the address to HCFGBAL (MSB must be cleared).

3. Write the higher byte of the address to HCFGBAH.

4. Set HCFGLK bit to prevent an accidental change of the address written to HCFGBAL and HCFGBAH.

The base address is preserved by VCC, and VHCFGA is set as long as a valid address is maintained. If there is no valid

configuration base address, the LPC interface does not respond to configuration requests.

Host Keyboard Fast Reset

The Host Keyboard Reset output (KBRST) is an output of the PC87591x that serves as one of the sources for Host Soft

reset commands (i.e., INIT input in the x86 processors). Figure 107 shows the KBRST generation scheme. The host is reset

when the KBRST output is low. A reset command is issued by the PC87591x by software or hardware, as follows:

●Software: The core ﬁrmware can issue a reset command to the host by writing 1 to HRSTOB in MSWCTL1 register.

The reset to the host ends by writing 0 to this bit.

●Hardware: The host is reset during VCC Power-Up reset if HRAPU bit in MSWCTL3 register is set and an LPC trans-

action is started. This is used to prevent accesses to the PC87591x from being ignored due to the duration of the

Power-Up reset.

GA20 Pin Functionality

The GA20 (Gate Address A20) function is part of the PC architecture. In PC87591x, the GA20 function is implemented by a

GPIO signal that is configured as output. Port PB5 is recommended to be used as GA20 since its default state after reset is

output driving high. The firmware running on the core may change the GA20 signal state by modifying bit 5 in PBDOUT reg-

ister. There is no special hardware or multiplexing on PB5; since there is no multiplexing, bit 5 of PBALT register is always

0 and any writes to it are disregarded. PB5 may be used as a GPIO; however, note that wake-up for PB5 differs from the

other signals in port B.

Host Reset

Extend Logic

Figure 107. KBRST Generation Scheme

HRSTOB bit (MSWCTL1)

HRAPU bit (MSWCTL3) =1

VCC Power-Up Reset

IOPB6

Logic

LPFTO bit (MSWCLT3) =1

LPCPD = 0

LPC Transaction Detected

KBRST

Host Controller Interface Modules (Continued)

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5.5.5 MSWC Host Registers

The MSWC registers are organized in four banks, all of which are battery-backed. The offsets are related to a base address

that is determined by the MSWC Base Address register in the device configuration registers. The lower 19 offsets are com-

mon to the four banks; the upper offsets (1316-1F16) are divided as follows:

●Bank 0 is reserved.

●Bank 1 is reserved.

●Bank 2 holds the Event Routing Conﬁguration and Wake-Up Extension Control registers.

The active bank is selected through the Configuration Bank Select field (bits 1-0) in the Wake-Up Configuration register

(WK_CFG).

As a programing aid, the registers are described in this chapter according to the following functional groupings:

●General status

●Enable

●Conﬁguration

●Routing

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

MSWC Host Register Map

The following tables list the MSWC host registers. For the MSWC core register map, see Section 5.5.6 on page 328.

Table 44. Banks 0, 1, 2 and 3 - The Common Control and Status Register Map

Table 45. Bank 2 - Event Routing Conﬁguration Register Map

Wake-Up Event Status Register 0 (WK_STS0)

This register is set to 0016 on VPP power-up, VCC power-up or Host Domain Software reset. It indicates which wake-up

events, associated with the register, have occurred. Writing 1 to a bit clears it to 0. Writing 0 has no effect. Bit 6 behaves in

a special way, as described in the table below.

Location: Offset 0016

Type: R/W1C

Offset Mnemonic Register Name Type

0016 WK_STS0 Wake-Up Event Status 0 R/W1C

0216 WK_EN0 Wake-Up Enable 0 R/W

0416 WK_CFG Wake-Up Conﬁguration R/W

0616 WK_SIGV Wake-Up Signal Value RO

0716 WK_STATE Wake-Up ACPI State WO

Other Reserved

Offset Mnemonic Register Name Type

1316 WK_SMIEN0 Wake-Up SMI Enable 0 R/W

1516 WK_IRQEN0 Wake-Up Interrupt Request Enable 0 R/W

Other Reserved

Bit 76543210

Name Module IRQ

Event

Status

Software

Event

Status Reserved RING

Event

Status Reserved RI2

Event

Status

RI1

Event

Status

Reset 00000000

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Wake-Up Events Enable Register (WK_EN0)

This register is set to 0016 on VPP power-up or Host Domain Software reset. When enabled wake-up events are detected,

the PWUREQ signal is activated.

Location: Offset 0216

Type: R/W

Bit Description

0RI1 Event Status.

0: Event not detected (default)

1: Event detected

1RI2 Event Status.

0: Event not detected (default)

1: Event detected

2Reserved.

3RING Event Status. RING event detection, according to the RING detection mode enabled.

0: Event not detected (default)

1: Event detected

5-4 Reserved.

6Software Event Status. This bit may work in two modes, as deﬁned by HSECM bit in MSWCTL1 register (see

“MSWC Control Status Register 1 (MSWCTL1)” on page 329).

When HSECM is 0, writing 1 to Software Event Status bit inverts its value.

When HSECM is 1, writing 1 to Software Event Status bit sets it; the bit is cleared by a write of 1 to bit 6 in

MSHES0 register.

0: Event not active (default)

1: Event active

7Module IRQ Event Status. This sticky bit shows the status of the module IRQ event detection.

0: Event not active (default)

1: Event active

Bit 76543210

Name Module IRQ

Event

Enable

Software

Event

Enable Reserved RING

Event

Enable Reserved RI2

Event

Enable

RI1

Event

Enable

Reset 00000000

Bit Description

0RI1 Event Enable.

0: Disabled (default)

1: Enabled

1RI2 Event Enable.

0: Disabled (default)

1: Enabled

2Reserved.

3RING Event Enable.

0: Disabled (default)

1: Enabled

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Wake-Up Conﬁguration Register (WK_CFG)

This register is set to 0016 on VPP power-up or Host Domain Software reset. It enables access to Event Routing Control

registers (bank selected).

Location: Offset 0416

Type: R/W

Wake-Up Signals Value Register (WK_SIGV)

This is a read-only register that returns the value of SMI and PWUREQ signal output and input to this module. This register

helps to identify the source of the wake-up request when multiple sources are enabled.

Location: Offset 0616

Type: RO

5-4 Reserved.

6Software Event Enable.

0: Disabled (default)

1: Enabled

7Module IRQ Event Enable.

0: Disabled (default)

1: Enabled

Bit 76543210

Name Reserved Conﬁguration Bank

Select

Reset 00000000

Required 0 0

Bit Description

1-0 Conﬁguration Bank Select.

Bits

1 0 Bank Register

0 0: 0 Reserved

0 1: 1 Reserved

1 0: 2 Event Routing, Wake-Up Extension

1 1: 3 Reserved

7-2 Reserved.

Bit 76543210

Name Reserved PWUREQof

Wake-Up

Value

PWUREQ

Output

Value

PM2 SMI

Output

Value

PM1 SMI

Output

Value

SMI Wake-

Up Output

Value

SMI Output

Value

Bit Description

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Wake-Up ACPI State Register (WK_STATE)

This is a read/write register. It always returns 0016 when read.

Location: Offset 0716

Type: R/W

Bit Description

0SMI Output Value.

0: SMI output is low (asserted)

1: SMI output is high (de-asserted)

1SMI Wake-Up Output Value.

0: SMI output of the wake-up module is low (asserted)

1: SMI output of the wake-up module is high (de-asserted)

2PM1 SMI Output Value.

0: SMI output of the Power Management channel 1 is low (asserted)

1: SMI output of the Power Management channel 1 is high (de-asserted)

3PM2 SMI Output Value.

0: SMI output of the Power Management channel 2 is low (asserted)

1: SMI output of the Power Management channel 2 is high (de-asserted)

4PWUREQ Wake-Up Output Value.

0: PWUREQ output is low (asserted)

1: PWUREQ output is high (de-asserted)

5PWUREQ Wake-Up Value.

0: PWUREQ output of the wake-up module is low (asserted)

1: PWUREQ output of the wake-up module is high (de-asserted)

7-6 Reserved.

Bit 76543210

Name Reserved S5 S4 S3 S2 S1 Reserved

Bit Description

0Reserved.

1S1 (Request to Change to S1 State). A write of 1 to this bit indicates to the core that the host requests to

change to S1 state. The S state and transition are interpreted, as speciﬁed in the ACPI standard for S state

change requests. This bit always reads back 0.

0: Not an S1 state request

1: S1 state setting request

2S2 (Request to Change to S2 State). A write of 1 to this bit indicates to the core that the host requests to

change to S2 state. The S state and transition are interpreted, as speciﬁed in the ACPI standard for S state

change requests This bit always reads back 0.

0: Not an S2 state request

1: S2 state setting request

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Wake-Up Event Routing to SMI Enable Register 0 (WK_SMIEN0)

This register is set to 0016 on VPP power-up or Host Domain software reset. It controls the routing of detected wake-up

events to the SMI signal. Detected wake-up events that are enabled activate the SMI signal regardless of the value of

WK_EN0 register.

Location: Bank 2, Offset 1316

Type: R/W

3S3 (Request to Change to S3 State). A write of 1 to this bit indicates to the core that the host requests to

change to S3 state. The S state and transition are interpreted, as speciﬁed in the ACPI standard for S state

change requests. This bit always reads back 0.

0: Not an S3 state request

1: S3 state setting request

4S4 (Request to Change to S4 State). A write of 1 to this bit indicates to the core that the host requests to

change to S4 state. The S state and transition are interpreted, as speciﬁed in the ACPI standard for S state

change requests. This bit always reads back 0.

0: Not an S4 state request

1: S4 state setting request

5S5 (Request to Change to S5 State). A write of 1 to this bit indicates to the core that the host requests to

change to S5 state. The S state and transition are interpreted, as speciﬁed in the ACPI standard for S state

change requests. This bit always reads back 0.

0: Not an S5 state request

1: S5 state setting request

7-6 Reserved.

Bit 76543210

Name Reserved Software

Event to

SMI Enable Reserved RING

Event to

SMI Enable Reserved RI2

Event to

SMI Enable

RI1

Event to

SMI Enable

Reset 00000000

Bit Description

0RI1 Event to SMI Enable.

0: Disabled (default)

1: Enabled

1RI2 Event to SMI Enable.

0: Disabled (default)

1: Enabled

2Reserved.

3RING Event to SMI Enable.

0: Disabled (default)

1: Enabled

5-4 Reserved.

6Software Event to SMI Enable.

0: Disabled (default)

1: Enabled

7Reserved.

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Wake-Up Event Routing to IRQ Enable Register 0 (WK_IRQEN0)

This register is set to 0016 on VPP power-up or Host Domain Software reset. It controls the routing of detected wake-up

events to the assigned MSWC interrupt request (IRQ) channel. Detected wake-up events that are enabled activate the as-

signed IRQ channel regardless of the value of WK_EN0 register.

Location: Bank 2, Offset 1516

Type: R/W

5.5.6 MSWC Core Registers

For a summary of the abbreviations used for Register Type, see Section 2 on page 34.

Table 46. MSWC Core Register Map

Bit 76543210

Name Reserved Software

Event to

IRQ Enable Reserved RING

Event to

IRQ Enable Reserved RI2

Event to

IRQ Enable

RI1

Event to

IRQ Enable

Reset 00000000

Bit Description

0RI1 Event to IRQ Enable.

0: Disabled (default)

1: Enabled

1RI2 Event to IRQ Enable.

0: Disabled (default)

1: Enabled

2Reserved.

3RING Event to IRQ Enable.

0: Disabled (default)

1: Enabled

5-4 Reserved.

6Software Event to IRQ Enable.

0: Disabled (default)

1: Enabled

7Reserved.

Mnemonic Register Name Type

MSWCTL1 MSWC Control Status Register 1 Varies per bit

MSWCTL2 MSWC Control Status Register 2 Varies per bit

MSWCTL3 MSWC Control Status Register 3 R/W

HCFGBAL Host Conﬁguration Base Address Low R/W

HCFGBAH Host Conﬁguration Base Address High R/W

MSIEN2 MSWC Interrupt Enable Register 2 R/W

MSHES0 MSWC Host Event Status Register 0 R/W1C

MSHEIE0 MSWC Host Event Interrupt Enable Register R/W

Host Controller Interface Modules (Continued)

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MSWC Control Status Register 1 (MSWCTL1)

This is a byte-wide read/write register that controls the settings associated with host wake-up and activity. The contents of

this register are preserved by VCC. Bit 0 is cleared by Warm reset; other bits are reset only on VCC Power-Up reset.

Location: 00 FCC016

Type: Varies per bit

Bit 76543210

Name Reserved HSECM HCFGLK VHCFGA LPCRSTA HPWRON HRSTOB

Reset 000000- -

Bit Type Description

0 R/W HRSTOB (Host Reset Out Bit). Enables the PC87591x to generate a Host Soft reset via ﬁrmware,

using the KBSTO pin. The pin is held low (reset is active) for as long this bit 1.

0: KBRST is not forced active (default)

1: Force KBRST active

1ROHPWRON (Host Power On). The VDD power detection logic indicates that VDD is on.

0: VDD is off (below VDDON)

1: VDD is on (above VDDON)

2ROLPCRSTA (LPC Reset Active). The RESET1 input is active (low).

0: RESET1 is not active (high)

1: RESET1 is active (low)

3 R/W1C VHCFGA (Valid Host Conﬁguration Address). This bit is set by a write to HCFGBAH register, as

detailed in the update sequence in “Host Conﬁguration Address Selection” on page 322. The ﬁrmware

can clear the bit by writing 1 to it. This register is used as the address of the Conﬁguration registers

when the PC87591x is set to operate with the internal base address. Writing 0 to this bit is ignored.

This bit can be locked and made read-only by setting HCFGLK (bit 4).

0: Host Configuration Registers base address is not valid and access to this registers by the host is not

enabled (default)

1: Host Configuration Registers base address is specified in HCFGBAH and HCFGBAL registers

4 R/W1S HCFGLK (Host Conﬁguration Address Lock). This bit is cleared during VCC power-up,

WATCHDOG reset or Debugger Interface reset, but is unchanged during other reset events.

When 1 is written to this bit, it becomes read only (i.e., it cannot be cleared by the ﬁrmware) and locks

VHCFGA bit, HCFGBAH register and HCFGBAL register, preventing accidental alteration to them.

0: Allows update of the Host Configuration Registers base address (default)

1: Locks the Host Configuration Registers base address

5 R/W1C HSECM (Host Software Event Clear Mode). Controls the clear mode of Host Software Event Status

bit in WK_STS0. This bit is cleared at VCC power-up and RESET1 events.

0: Host Software Event Status bit in WK_STS0 (bit 6) toggles on host writes of 1. MSHES0 bit 6 is set

when WK_STS0 bit 6 changes from 0 to 1 (default).

1: Host Software Event Status bit in WK_STS0 (bit 6) and MSHES0 bit 6 are both cleared by writes of

1 to MSHES0 register

7-6 Reserved.

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MSWC Control Status Register 2 (MSWCTL2)

This is a byte-wide read/write register that controls the settings associated with host wake-up and activity. Bits in this register

are cleared by VCC Power-Up and RESET1 resets.

Location: 00 FCC216

Type: Varies per bit

MSWC Control Status Register 3 (MSWCTL3)

This is a byte-wide read/write register that controls the settings associated with host wake-up and activity. The contents of

this register is preserved by VPP and it is reset only on VPP Power-Up reset.

Location: 00 FCC416

Type: R/W

Bit 76543210

Name CFGPSO CFGPBM ACPIS5 ACPIS4 ACPIS3 ACPIS2 ACPIS1 ACPIS0

Reset 00000000

Bit Type Description

0 R/W1C ACPIS0 (ACPI request for S0). This bit may be used by ACPI software to directly request a change of

power state. This bit is set when the host software writes a value of 0 to bits S1 through S5 in

WK_STATE register. This bit is cleared by writing 1 to it. A write of 0 is ignored.

0: No pending request for S0 change (default)

1: A request for S0 change was detected

5-1 R/W1C ACPIS1-5 (ACPI request for S1 through S5). These bits may be used by ACPI software to directly

request a change of power state. These bits are set by a host software write of 1 to the respective bit in

WK_STATE register. The bit is cleared by writing 1 to it. A write of 0 is ignored.

When any ACPIS0 through ACPIS5 bit is set, an APC interrupt to the core, using a MIWU input, is

asserted.

6ROCFGPBM (SuperI/O Conﬁguration Register D Power Button Mode). This bit reﬂects the current status

of the Power Button Mode bit in SIOCFD register. This bit may be used by the host software to specify

to the core he method used for power off signaling. See “SuperI/O Conﬁguration D Register (SIOCFD)”

on page 347

A write of 1 clears the interrupt signal caused by a change in this bit value. A write of 0 to this bit is

ignored.

7ROCFGPSO (SuperI/O Conﬁguration Register D Power Supply Off). This bit is set whenever a 1 is

written to the Power Supply Off bit in SIOCFD register. This bit may be used by the host software to

specify to the core that the power supply should be turned off, in a non-ACPI system. See “SuperI/O

Conﬁguration D Register (SIOCFD)” on page 347.

A write of 1 clears this bit and the interrupt signal caused by a change in this bit value. A write of 0 to

this bit is ignored.

Bit 76543210

Name Reserved RTCAL LPFTO HRAPU

Reset 00000001

Host Controller Interface Modules (Continued)

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Host Conﬁguration Base Address Low (HCFGBAL)

This is a byte-wide read/write register that holds the lower byte of the Host Configuration Registers base address. Bit 0 of

this register is always forced to 0 to guarantee address alignment. This register is cleared on VCC Power-Up reset.

Location: 00 FCC816

Type: R/W

Host Conﬁguration Base Address High (HCFGBAH)

This is a byte-wide read/write register that holds the higher byte of the Host Configuration Registers base address. This reg-

ister is cleared on VCC Power-Up reset.

Location: 00 FCCA16

Type: R/W

MSWC Interrupt Enable Register 2 (MSIEN2)

This is a byte-wide read/write register that holds enable bits for interrupt generation to the core through the MIWU (level high)

for the respective bits in MSWCTL2 and MSWCTL3 registers. The interrupt may be cleared by clearing the status bit or

masking the interrupt. On Warm reset, this register is cleared (0016).

Location: 00 FCCC16

Type: R/W

Bit Description

0HRAPU (Host Reset when Accessed During VCC Power-Up Reset). Indicates that a reset should be sent to

the host if LPC activity was detected while the VCC Power-Up reset was not completed. This intends to re-start

any LPC transaction that may have addressed the PC87591x but could not be handled correctly. When

HCFGLK bit is set, writes to this bits are ignored.

0: Do not generate a reset on LPC transactions while the PC87591x is in Power-Up reset

1: Assert KBRST output on LPC transactions while the PC87591x is executing the VCC Power-Up reset sequence

(default)

1LPFTO (LPC Power Fail Turn Off KBRST and GA20). Indicates the handling of KBRST and GA20 outputs

when LPCPD is active.

0: Ignore LPCPD in handling these signals (default)

1: Force the two signals low while LPCPD is active or VDD is low

2RTCAL (RTC Alarm). Indicates that an RTC Alarm event occurred. This bit is set on the rising edge of the RTC

Alarm output. It is cleared by writing 1 to it. Note that the ALARM event detection is edge triggered by the

RTCAL bit; thus for a new event to be detected, ﬁrst RTCAL bit and then Alarm Status bit in the RTC must be

cleared.

0: No RTC Alarm is flagged (default)

1: RTC Alarm rising edge was detected

7-3 Reserved.

Bit 76543210

Name Host Conﬁguration Registers Base Address Low

Reset 00000000

Bit 76543210

Name Host Conﬁguration Registers Base Address High

Reset 00000000

Host Controller Interface Modules (Continued)

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MSWC Host Event Status Register 0 (MSHES0)

This register holds information similar to that in WK_STS0 register. The same event that causes a WK_STS0 bit to be set

sets the respective bit in MSHES0 register. Clearing bits is done for each of the status registers separately. This register is

reset to 0016 on VCC power-up or Host Domain Software reset. Writing 1 to a bit clears it to 0. Writing 0 has no effect. Bit 6

of this register behaves in a special way on set and clear, as described below.

Location: Offset 00 FCCE16

Type: R/W1C

Bit 76543210

Name EICFGPSO EICFGPBM EIACPIS5 EIACPIS4 EIACPIS3 EIACPIS2 EIACPIS1 EIRTCAL

Reset 00000000

Bit Description

0EIRTCAL (Enable Interrupt on RTC Alarm). Mask generation of interrupt to the core on setting of the RTC

Alarm bit in MSWCTL1 register.

0: Interrupt disabled (default)

1: Generate a level high interrupt when the RTC Alarm bit is set

5-1 EIACPIS5-1 (Enable Interrupt ACPI request for S5 through S1). Mask generation of interrupt to the core on

changes to ACPISi (i=5-1) bit in MSWCTL2 register. An interrupt enable for ACPIS0 is enabled when any of

these bits is set.

0: Interrupt disabled (default)

1: Generate a level high interrupt on any change to the ACPISi bit

6EICFGPBM (Enable Interrupt SuperI/O Conﬁguration Register D Power Button Mode). Mask generation of

interrupt to the core on changes to CFGPBM bit in MSWCTL2 register.

0: Interrupt disabled (default)

1: Generate a level high interrupt on any change to the CFGPBM bit

7EICFGPSO (Enable Interrupt SuperI/O Conﬁguration Register D Power Supply Off). Mask generation of

interrupt to the core on changes to CFGPSO bit in MSWCTL2 register.

0: Interrupt disabled (default)

1: Generate a level high interrupt on any change to the CFGPBM bit

Bit 76543210

Name Module IRQ

Event

Status

Software

Event

Status Reserved RING

Event

Status Reserved RI2

Event

Status

RI1

Event

Status

Reset 00000000

Bit Description

0RI1 Event Status.

0: Event not detected (default)

1: Event detected

1RI2 Event Status.

0: Event not detected (default)

1: Event detected

2Reserved.

Host Controller Interface Modules (Continued)

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MSWC Host Event Interrupt Enable Register (MSHEIE0)

This register is cleared to 0016 on Warm reset. It enables a core interrupt through the MIWU (level high) for the respective

bit in the mobile MSHES0 register. The interrupt may be cleared by clearing the status bit or masking the interrupt.

Location: Offset 00 FCD016

Type: R/W

3RING Event Status. RING event detection, according to the RING detection mode enabled.

0: Event not detected (default)

1: Event detected

5-4 Reserved.

6Software Event Status. This bit indicates a host software event. It may operate in two modes depending on

HSECM bit in MSWCTL1 register.

When HSECM is cleared, this bit is set when bit 6 of WK_STS0 changes from 0 to 1.

When HSECM is set, this bit is set on a write of 1 to WK_STS0 bit 1.

This bit is cleared by writing 1 to it.

0: Event not active (default)

1: Event active

7Module IRQ Event Status. This sticky bit shows the status of the module IRQ event detection.

0: Event not active (default)

1: Event active

Bit 76543210

Name Module IRQ

Event

Enable

Software

Event

Enable Reserved RING

Event

Enable Reserved RI2

Event

Enable

RI1

Event

Enable

Reset 00000000

Bit Description

0RI1 Event Enable.

0: Disabled (default)

1: Enabled

1RI2 Event Enable.

0: Disabled (default)

1: Enabled

2Reserved.

3RING Event Enable.

0: Disabled (default)

1: Enabled

5-4 Reserved.

6Software Event Enable.

0: Disabled (default)

1: Enabled

7Module IRQ Event Enable.

0: Disabled (default)

1: Enabled

Bit Description

Host Controller Interface Modules (Continued)

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5.5.7 Usage Hints

PWUREQ Output Connection

The PWUREQ concentrates a set of wake-up and other power management events in the PC87591x. In typical use, this

signal is connected to one of the chipset inputs that drive SCI event to the host.

RESET2 Events

When RESET2 is used to reset the host domain, some of the MSWC functions may need to be set to their default values

when a falling edge of the RESET2 is detected. An interrupt routine triggered by this event may be used for this task. The

following functions should be reset:

●GA20

●KBRST

●Host Registers: WK_EN0, WK_SMIEN0 and WK_IRWEN0;

Use the “Core Access to Host-Controlled Modules” for this operation (see Section 5.4 on page 313).

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6.0 Host-Controlled Modules and Host Interface

6.1 DEVICE ARCHITECTURE AND CONFIGURATION

The PC87591x Host-Controlled Functions comprises a collection of generic and proprietary functional blocks. Each func-

tional block is described in a separate chapter in this document. However, some parameters in the implementation of the

functional blocks may vary per function and/or device. This chapter describes the PC87591x structure and provides all log-

ical device-specific information, including special implementation of generic blocks, system interface and device configura-

tion.

The PC87591x Host-Controlled Functions consist of seven logical devices (involving six modules), the host interface and a

central set of configuration registers, all built around a central internal bus. The internal bus is similar to an 8-bit ISA bus

protocol. Figure 108 illustrates the blocks and their interconnection.

The LPC Bus Interface serves as a bridge between the external LPC interface and the internal bus. It supports the following

operations, as defined in Intel’s LPC Interface Speciﬁcation, Revision 1.0:

●8-bit I/O read

●8-bit I/O write

●8-bit Memory read

●8-bit Memory write

●8-bit FWH read

●8-bit FWH write

The Configuration and Control register set supports ACPI-compliant PnP configuration. The configuration registers are

structured as a subset of the Plug and Play Standard registers, defined in Appendix A of the Plug and Play ISA Specification,

Revision 1.0a by Intel and Microsoft, and are similar to those used in National SuperI/O devices. All system resources as-

signed to the functional blocks (I/O address space, and IRQ lines) are configured in and managed by this register set. In

addition, some function-specific parameters are configurable through the configuration registers and distributed to the func-

tional blocks through special control signals.

6.1.1 Configuration Structure and Access

The configuration structure comprises a set of banked registers that are accessed via a pair of specialized registers.

The Index-Data Register Pair

Access to the Host-Controlled Functions configuration registers is via an Index-Data register pair, using two system I/O byte

locations. The base address of this register pair is determined during VCC Power-Up reset, according to the state of the hard-

ware strapping option on the BADDR1-0 pins. Table 47 shows the selected base addresses as a function of BADDR1-0 (see

Section 2.2.11 on page 50).

Table 47. BADDR1-0 Strapping Options

The Index register is an 8-bit read/write register located at the selected base address (Base+0). It is used as a pointer to the

configuration register file and holds the index of the configuration register that is currently accessible via the Data register.

Reading the Index register returns the last value written to it (or a default of 0016 after Host Domain reset).

The Data register is an 8-bit register located at the selected base address (Base+1) used as a data path to any configuration

register. Accessing the Data register actually accesses the configuration register that the Index register is currently pointed

to.

BADDR1-0 I/O Address

Index Register Data Register

00 2E

16 2F16

01 4E

16 4F16

1. See “Host Conﬁguration Address Selection” on page 322 for more

details about this option.

(HCFGBAH,HCFGBAL) (HCFGBAH,HCFGBAL)+1

1 1 Reserved

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Figure 108. Host-Controlled Domain Detailed Block Diagram

Banked Logical Device Registers Structure

Each functional block is associated with a Logical Device Number (LDN). The configuration registers are grouped into banks,

where each bank holds the standard configuration registers of the corresponding logical device. Table 48 shows the LDN

values of the PC87591x functional blocks. Any value not listed is reserved.

Figure 109 shows the structure of the standard configuration register file. The Host-Controlled Functions control and config-

uration registers are not banked and are accessed by the Index-Data register pair only, as described above. However, the

device control and device configuration registers are duplicated over seven banks for the seven logical devices. Therefore,

two-dimensional indexing is used to access a specific register in a specific bank: the LDN register selects the bank (or logical

device) and the Index register selects the register within the bank. Accessing the Data register while the Index register holds

a value of 3016 or higher physically accesses the logical device configuration registers currently pointed to by the Index reg-

ister, within the logical device currently selected by the LDN register.

Internal Bus

LPC

Control Signals

Interface

LCLK

RESET1-2

LAD3-0

LFRAME

LDRQ

SERIRQ

RI1

RI2

SMI

BADDR0-1

& Control

Registers

Conﬁg

Shared

Strap

Conﬁg

CLKRUN

LPCPD

Bus

RTC

BIOS

Security

System

Wake-Up

Control

Mobile

Peripheral Bus

Core Bus

SHBM

HCFGBAH, HCFGBAL

KBC

Host I/F

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Figure 109. Structure of Standard Conﬁguration Register File

Table 48. Logical Device Number (LDN) Assignments

Write accesses to unimplemented registers (i.e., accessing the Data register while the Index register points to a non-existing

register) are ignored; reads return 0016 for all addresses except 7416 and 7516 (DMA configuration registers), which return 0416

(indicating that no DMA channel is active). The configuration registers are accessible immediately after Host Domain reset.

Standard Logical Device Conﬁguration Register Deﬁnitions

In the registers below, any undefined bit is reserved. Unless otherwise noted, the following definitions also hold true:

●All registers are read/write.

●All reserved bits return 0 on reads except where noted. To prevent unpredictable results, do not modify these bits.

Use read-modify-write to prevent the values of reserved bits from being changed during write.

●Write-only registers should not use read-modify-write during updates.

LDN Functional Block

0416 Mobile System Wake-Up Control (MSWC)

0516 Keyboard and Mouse Controller (KBC) - Mouse Interface

0616 Keyboard and Mouse Controller (KBC) - Keyboard Interface

0F16 Shared BIOS and Security

1016 Real Time Clock

1116 Power Management I/F Channel 1

1216 Power Management I/F Channel 2

0716

2016

3016

6016

7516

FE16

Logical Device Number Register

SuperI/O Configuration Registers

Logical Device Control Register

Standard Logical Device

Special (Vendor-Defined)

Configuration Registers

Banks

2F16

F016 Bank Select

6316

7416

7016

7116 Configuration Registers

(One per Logical Device)

Logical Device

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Table 49. Standard Control Registers

Table 50. Logical Device Activate Register

Table 51. I/O Space Conﬁguration Registers

Index Register Name Description

0716 Logical Device

Number This register selects the current logical device. See Table 48 for valid numbers. All

other values are reserved.

2016 -2F

16 SuperI/O

Conﬁguration SuperI/O conﬁguration registers and ID registers

Index Register Name Description

3016 Activate Bits 7-1: Reserved

Bit 0: Logical device activation control

0: Disabled

1: Enabled

Index Register Name Description

6016 I/O Port Base

Address Bits (15-8)

Descriptor 0

Indicates selected I/O lower limit address bits 15-8 for I/O Descriptor 0.

6116 I/O Port Base

Address Bits (7-0)

Descriptor 0

Indicates selected I/O lower limit address bits 7-0 for I/O Descriptor 0.

6216 I/O Port Base

Address Bits (15-8)

Descriptor 1

Indicates selected I/O group 2 lower limit address bits 15-8 for I/O Descriptor 1.

6316 I/O Port Base

Address Bits (7-0)

Descriptor 1

Indicates selected I/O group 2 lower limit address bits 7-0 for I/O Descriptor 1.

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Table 52. Interrupt Conﬁguration Registers

Table 53. DMA Conﬁguration Registers

Table 54. Special Logical Device Conﬁguration Registers

Index Register Name Description

7016 Interrupt Number

and Wake-Up on

IRQ Enable

Indicates selected interrupt number.

Bits 7-5: Reserved.

Bit 4: Enables wake-up on the IRQ of the logical device. When enabled, IRQ as-

sertion triggers a wake-up event.

0: Disabled (default)

1: Enabled

Bits 3-0: select the interrupt number. A value of 1 selects IRQ1, a value of 2 selects

IRQ2, etc. (up to IRQ15). A value of 0 disables this interrupt.

7116 Interrupt Request

Type Select Indicates the type and level of the interrupt request number selected in the previous

Bits 7-2: Reserved.

Bit 1: Polarity of interrupt request selected in previous register

0: Low polarity

1: High polarity

Bit 0: Type of interrupt request selected in previous register

0: Edge

1: Level

Index Register Name Description

7416 DMA Channel

Select 0 Indicates selected DMA channel for DMA 0 of the logical device (0: The ﬁrst DMA

channel if more than one DMA channel is used).

Bits 7-3: Reserved.

Bits 2-0: Select the DMA channel for DMA 0. The valid choices are 0-3, where:

●A value of 0 selects DMA channel 0, 1 selects channel 1, etc.

●A value of 4 indicates that no DMA channel is active.

●The values 5-7 are reserved.

7516 DMA Channel

Select 1 Indicates selected DMA channel for DMA 1 of the logical device (1: The second

DMA channel if more than one DMA channel is used).

Bits 7-3: Reserved.

Bits 2-0: Select the DMA channel for DMA 1. The valid choices are 0-3, where:

●A value of 0 selects DMA channel 0, 1 selects channel 1, etc.

●A value of 4 indicates that no DMA channel is active.

●The values 5-7 are reserved.

Index Register Name Description

F016-FE16 Logical Device

Conﬁguration Special (vendor-deﬁned) conﬁguration options

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6.1.2 Standard Configuration Registers

SuperI/O Control and Conﬁguration Registers

The SuperI/O configuration registers at indexes 2016 and 2716 are mainly used for part identification, global power manage-

ment and the selection of pin multiplexing options. For details, see Section 6.1.8 on page 343.

Logical Device Control and Conﬁguration Registers

A subset of these registers is implemented for each logical device. See the functional block descriptions in Chapter 5 on

page 277 and Chapter 6 on page 335.

Control

The only implemented control register for each logical device is the Activate register at index 3016. Bit 0 of Activate register

controls the activation of the associated functional block. Activation enables access to the functional block’s registers and

attaches the functional block’s system resources (e.g., address space and interrupts), which are unused as long as the block

is not activated. Other effects may apply on a function-specific basis (such as clock enable and active pinout signaling).

SuperI/O Control and

Conﬁguration Registers

Logical Device Control and

one per Logical Device

Conﬁguration Registers -

Index Register Name

0716 Logical Device Number

2016 SuperI/O ID

2116 SuperI/O Conﬁguration 1

2516 SuperI/O Conﬁguration 5

2616 SuperI/O Conﬁguration 6

2716 SuperI/O Revision ID

2816 SuperI/O Conﬁguration 8

2916 SuperI/O Conﬁguration 9

2D16 SuperI/O Conﬁguration D

2B16 -2E

16 Reserved exclusively for National use

3016 Logical Device Control (Activate)

6016 I/O Base Address Descriptor 0 Bits 15-8

6116 I/O Base Address Descriptor 0 Bits 7-0

6216 I/O Base Address Descriptor 1 Bits 15-8

6316 I/O Base Address Descriptor 1 Bits 7-0

7016 Interrupt Number and Wake-Up on IRQ Enable

7116 IRQ Type Select

7416 DMA Channel Select 0

7516 DMA Channel Select 1

F016 -F9

16 Device Speciﬁc Logical Device Conﬁguration 1 to 10

(some are optional)

Figure 110. Conﬁguration Register Map

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Standard Conﬁguration

The standard configuration registers manage the PnP resource allocation to the functional blocks. The I/O port base address

(descriptor 0) is a pair of registers at index 60-6116, holding the first 16-bit base address for the register set of the functional

block. An optional 16-bit second base-address (descriptor 1) at index 62-6316 is used for logical devices with more than one

continuous register set. Interrupt Number and Wake-Up on IRQ Enable (index 7016) and IRQ Type Select (index 7116) reg-

isters allocate an IRQ number to the module’s interrupt and control the interrupt type and polarity. DMA Channel Select 0

(index 7416) allocates a DMA channel to the block, where applicable. DMA Channel Select 1 (index 7516) allocates a second

DMA channel, where applicable.

Special Conﬁguration

The vendor-defined registers, starting at index F016 -F9

16, control function-specific parameters such as operation modes,

power saving modes, clock rate selection and non-standard extensions to generic functions.

6.1.3 Default Configuration Setup

The default configuration setup of the PC87591x Host-Controlled functions is set according to the following reset types (see

Section 3.2 on page 65):

●VPP Power-Up Reset

Resets VPP-retained SuperI/O functions, such as the RTC and the MSWC registers, whose values are retained by

VPP

●VCC Power-Up Reset

Resets the MSWC registers whose values are retained by VCC only.

●Host Domain Hardware Reset

—Resets all SuperI/O logical devices, with the exception of the Mobile System Wake-Up Control (MSWC) and the RTC

registers retained by VPP or VCC.

—Resets all SuperI/O conﬁguration registers.

●Host Domain Software Reset

—Resets all SuperI/O logical devices, except the MSWC and the RTC registers retained by VPP or VCC.

—Resets most bits in the SuperI/O conﬁguration registers. This reset does not affect register bits that are locked for

write access (see “SuperI/O Conﬁguration 6 Register (SIOCF6)” on page 345 and Table 47 on page 335).

If a Host Domain Hardware reset occurs, the PC87591x wakes up with the following default SuperI/O configuration setup:

—The conﬁguration base address is according to the BADDR strap pin value, as shown in Table 47 on page 335.

—All logical devices are disabled, with the exception of the MSWC and shared memory, which remain functional but

whose registers cannot be accessed.

If a Host Domain reset occurs (either Software or Hardware), the PC87591x wakes up with the following default SuperI/O

configuration setup:

—The legacy devices are assigned with their legacy system resource allocation.

—The National proprietary functions are not assigned with any default resources, and the default values of their base

addresses are all 0016.

6.1.4 Address Decoding

A full 16-bit address decoding is applied when accessing the configuration I/O space as well as the registers of the functional

blocks. However, the number of configurable bits in the base address registers varies for each logical device.

The lower 0, 1, 2, 3, 4 or 5 address bits are decoded within the functional block to determine the offset of the accessed reg-

ister within the logical device’s I/O range of 1, 2, 4, 8, 16 or 32 bytes, respectively. The rest of the bits are matched with the

base address register to decode the entire I/O range allocated to the logical device. Therefore, the lower bits of the base

address register are forced to 0 (read only), and the base address is forced to be 1, 2, 4, 8, 16 or 32 byte-aligned, according

to the size of the I/O range.

The base address of the KBC, PM channel 1 and PM channel 2 are limited to the I/O address range of 000016 to 07FX16

only (bits 11-15 are forced to 0). The addresses of other devices are configurable within the full 16-bit address range (up to

FFFF16).

In some special cases, other address bits are used for internal decoding (such as bit 2 in the KBC). The KBC has two I/O

descriptors with some implied dependency between them. For more details, see the description of the base address register

for each logical device.

The Shared Memory and Security module serves as a bridge from the LPC to the on-chip flash and off-chip expansion mem-

ory. For module control and security function registers, the 16-bit base address is applied through the configuration address

space. To access the registers, the lower four address bits are decoded within the Shared Memory module. The address

ranges in the LPC memory space and the FWH memory space, which are bridged to the shared memory, are defined in the

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SuperI/O configuration section for the shared memory bridge. The number of address bits used for this decoding varies ac-

cording to the specified zones and their sizes. See “Memory Range Programing” on page 350 and “Shared Memory Config-

uration Register” on page 351 for details about the address range specifications.

6.1.5 Interrupt Serializer

The Interrupt Serializer translates internal IRQ sources into serial interrupt request data transmitted over the SERIRQ bus.

Figure 111 shows the interrupt serialization mechanism.

Figure 111. Interrupt Serialization Mechanism

The internal IRQ signals are fed into an IRQ Mapping and Polarity Control block. This block maps them to their associated

IRQ slots. The IRQs are then fed into the Interrupt Serializer, where they are translated into serial data and transmitted over

the SERIRQ bus.

6.1.6 Protection

The PC87591x provides features to protect the Personal Computer (PC) at software levels. The PC can be locked to protect

configuration bits and to prevent alteration of the device hardware configuration and several types of configuration settings.

The use of all protection mechanisms is optional.

6.1.7 LPC Interface

LPC Transactions Supported

The PC87591x LPC interface responds to the following LPC transactions as part of the standard Host Bus interface:

—I/O read cycles

—I/O write cycles

In addition, the Shared Memory module uses the following transactions:

—8-bit memory read and write

—8-bit FWH read and write

LPC transactions conform with Intel’s LPC Interface Specification, Revision 1.0.

The LPC- FWH read and write protocols are similar to memory read and write cycles. The specifications of these cycles are

listed below. The Address, Data, TAR and SYNC cycles are as specified for LPC memory read and write cycles. The START

and ID fields are similar to the equivalent cycle in LPC memory read and write transactions but differ in the data placed on

the LAD signals (see details in the cycle description).

Note: The PC87591x supports FWH transactions from LPC controllers that accept wait-sync and long wait-sync cycles. With

other LPC controllers, use the indirect write mechanism in the Shared Memory module to perform write operations.

FWH Read Cycle

1. START: 110116 (0xD).

2. ID field: FWH ID nibble (compared with bits 7-4 of shared memory; see “Shared Memory Configuration Register” on

page 351).

3. Address: Eight address nibbles, MS nibble first; see usage below).

4. TAR (two cycles).

5. SYNC.

6. DATA: Two data nibbles, LS nibble first (D3-D0, D7-D4).

7. TAR (two cycles).

IRQ Mapping,

Enable and Polarity

Control

Internal

IRQ

Sources

Control

Signals

Interrupt

Serializer

LPC Interface

SERIRQ

IRQ1

IRQ15

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FWH Write Cycle:

1. START: 111016 (0xE).

2. ID field: FWH ID nibble (compared with bits 7-4 of shared memory; see “Shared Memory Configuration Register” on

page 351).

3. Address: Eight address nibbles MS nibble first (see usage below).

4. DATA: Two data nibbles, LS nibble first (D3-D0, D7-D4).

5. TAR (two cycles).

6. SYNC.

7. TAR (two cycles).

The ID field is compared with bits 7-4 of shared memory; see “Shared Memory Configuration Register” on page 351. If the

two match, the PC87591x continues handling the transaction; if they do not match, the current LPC-FWH transaction is ig-

nored.

LPC-FWH Address translation: The address field in the LPC-FWH transaction is constructed of eight nibbles. The first seven

correspond to the first LS seven address nibbles (A27-A0) as follows: The first nibble that appears corresponds to addresses

A27-A24, the second to A23-A20, until the seventh incoming nibble, which corresponds to addresses A3-A0. Incoming nib-

ble number eight is ignored. The MS bits of the 32-bit addresses are ‘1111’ (A31 - A28).

Core Interrupt

Whenever there is an LPC or FWH transaction that is responded to by any of the PC87591x logical devices, a positive pulse

is generated on the Host Access Wake-Up input of the MIWU module. This interrupt may be used to wake up the core for

handling any host activity.

CLKRUN Functionality

The PC87591x supports the CLKRUN I/O signal, the use of which is highly recommended in portable systems. This signal

is implemented according to the specification in PCI Mobile Design Guide, Revision 1.1, December 18, 1998. The PC87591x

supports operation with both a slow and stopped clock in ACPI state S0 (the system is active but is not being accessed).

The PC87591x drives the CLKRUN low to force the LPC bus clock into full speed operation when an IRQ is pending inter-

nally and waiting to be sent through the serial IRQ.

LPCPD Functionality

The PC87591x supports the LPCPD input. This signal is used when the VDD chip supply is not shared by all residents of the

LPC bus. The LPCPD signal conforms with Intel’s LPC Interface Specification, Revision 1.0. Note that if the PC87591x pow-

er supply exists while LPCPD is active, it is not mandatory to reset the PC87591x when LPCPD is de-asserted.

6.1.8 SuperI/O Configuration Registers

This section describes the SuperI/O configuration and ID registers (those registers with first level indexes in the range of

2016 - 2E16). See Table 55 for a summary and directory of these registers.

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

Table 55. SuperI/O Conﬁguration Registers

Index Mnemonic Register Name Power Well Type

2016 SID SuperI/O ID VDD RO

2116 SIOCF1 SuperI/O Conﬁguration 1 VDD Varies per bit

2216 -24

16 Reserved exclusively for National use

2516 SIOCF5 SuperI/O Conﬁguration 5 VDD R/W

2616 SIOCF6 SuperI/O Conﬁguration 6 VDD R/W

2716 SRID SuperI/O Revision ID VDD RO

2816 SIOCF8 SuperI/O Conﬁguration 8 VDD R/W

2916 SIOCF9 SuperI/O Conﬁguration 9 VDD R/W

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SuperI/O ID Register (SID)

This register contains the identity number of the chip. The PC87591x is identified by the value EC16.

Location: Index 2016

Type: RO

SuperI/O Conﬁguration 1 Register (SIOCF1)

Location: Index 2116

Type: Varies per bit

2A16 -2C

16 Reserved exclusively for National use

2D16 SIOCFD SuperI/O Conﬁguration D VPP R/W

2E16 Reserved exclusively for National use

Bit 76543210

Name Family ID

Reset EC16

Bit Description

7-0 Family ID. These bits identify a family of devices with similar functionality but with different options

implemented.

Bit 76543210

Name Reserved Number of DMA Wait

States Number of I/O Wait

States Software

Reset

SuperI/O

Devices

Enable

Reset 00010001

Bit Type Description

0 R/W SuperI/O Devices Enable. Controls the function enable of all the PC87591x SuperI/O logical devices,

except shared memory and Mobile System Wake-Up Control (MSWC). This bit enables the

simultaneous disabling of these modules using a write to a single bit.

0: All SuperI/O logical devices in the PC87591x are disabled, except MSWC and shared memory

1: Each SuperI/O logical device is enabled according to its Activate register (Index 3016) (default)

1WOSoftware Reset. Read always returns 0.

0: Ignored (default)

1: Triggers the Host Domain Software Reset event, which resets the logical devices (see Section 6.1.3

on page 341)

3-2 R/W Number of I/O Wait States.

Bits

3 2 Number

0 0: 0 (default)

0 1: 2

1 0: 6

1 1: 12

Table 55. SuperI/O Conﬁguration Registers (Continued)

Index Mnemonic Register Name Power Well Type

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SuperI/O Conﬁguration 5 Register (SIOCF5)

Location: Index 2516

Type: R/W

SuperI/O Conﬁguration 6 Register (SIOCF6)

Write access to this register can be inhibited by setting bit 7 of this register. Activation of each logical device (bits 0-4) is also

affected by bit 0 of the logical device Activate register, index 3016, and bit 0 of SIOCF1 register.

Location: Index 2616

Type: R/W

5-4 R/W Number of DMA Wait States.

Bits

5 4 Number

0 0: Reserved

0 1: 2 (default)

1 0: 6

1 1: 12

7-6 Reserved.

Bit 76543210

Name Reserved SMI to IRQ2

Enable Reserved

Reset 00000000

Bit Type Description

3-0 Reserved.

4 R/W SMI to IRQ2 Enable. Enables using slot number 2 in the serial IRQ protocol as an SMI interrupt in

parallel to or instead of using the dedicated pin.

0: Disabled (default)

1: Enabled

7-5 Reserved.

Bit 76543210

Name SIOCF6

Software

Lock

General-Purpose

Scratch RTC

Disabled Reserved

Reset 00000000

Bit Description

3-0 Reserved.

Bit Type Description

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SuperI/O Revision ID Register (SRID)

This register contains the ID number of the specific family member (Chip ID) and the chip revision number (Chip Rev). The

Chip Rev is incremented on each revision.

Location: Index 2716

Type: RO

SuperI/O Conﬁguration 8 Register (SIOCF8)

Location: Index 2816

Type: R/W

4RTC Disabled.

0: Enabled (default)

1: Disabled

6-5 General-Purpose Scratch.

7SIOCF6 Software Lock. When set to 1 by software, it and other bits in this register can be cleared only by Host

Domain Hardware reset.

0: Write access to bits 0-6 of this register enabled (default)

1: Bits 6-0 of this register are read only.

Bit 76543210

Name Chip ID Chip Rev

Reset See values in ﬁeld description XXXXX

Bit Description

4-0 Chip Rev. Identiﬁes the device revision.

7-5 Chip ID. Identiﬁes a speciﬁc device of the PC87591x family.

Bits

7 6 5 Device

0 0 0: PC87591E

0 0 1: PC87591S

1 0 0: PC87591 L

Other: Reserved

Bit 76543210

Name Reserved

Reset 0 0 0 00000

Bit Description

7-0 Reserved.

Bit Description

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SuperI/O Conﬁguration 9 Register (SIOCF9)

Location: Index 2916

Type: R/W

SuperI/O Conﬁguration D Register (SIOCFD)

This is a battery-backed register.

Location: Index 2D16

Type: R/W

Bit 76543210

Name Reserved Reserved

Reset 0 0 0 00001

Bit Description

7-0 Reserved.

Bit 76543210

Name Reserved Power

Supply Off

Power

Button

Mode

Reset 00000000

Bit Description

0Power Button Mode. This is a R/W bit. The value of this bit is available to the core through a register in the

MSWC; see Section 5.5 on page 318.

0: Legacy (default at VCC Power-Up reset)

1: ACPI

1Power Supply Off. This is a R/W bit. It always returns 0 when read. When using Legacy mode (bit 0 is set to

0) and setting this bit to 1, this bit indicates to the core that the host requests shutting down the power. The

value of this bit is available to the core by reading a register in the MSWC; see Section 5.5 on page 318.

0: No action (default at VPP Power-Up reset)

1: Indicates power shut down to the core in Legacy mode

7-2 Reserved.

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6.1.9 Mobile System Wake-Up Control (MSWC) Configuration

Logical Device 4 (MSWC) Conﬁguration

Table 56 lists the configuration registers that affect the MSWC. See Section 6.1.2 on page 340 for a detailed description of

these registers.

Table 56. Mobile System Wake-Up Control (MSWC) Conﬁguration Registers

6.1.10 Keyboard and Mouse Controller (KBC) Configuration

Logical Devices 5 and 6 (Mouse and Keyboard) Conﬁguration

Tables 57 and 58 list the configuration registers that affect the Mouse and the Keyboard respectively. Only the last register

(F016) is described here. See “Standard Logical Device Configuration Register Definitions” on page 337 and Section 6.1.2

on page 340 for descriptions of the other configuration registers.

Usage Hints: It is recommended to set the type of interrupt request as level and its level of interrupt as high.

Table 57. Mouse Conﬁguration Registers

Index Conﬁguration Register or Action Type Reset

3016 Activate. When bit 0 is cleared, the registers of this logical device are not

accessible.1

1. The logical device registers are maintained, and all wake-up detection mechanisms are functional.

R/W 0016

6016 Base Address MSB register. R/W 0016

6116 Base Address LSB register. Bits 4-0 (for A4-0) are read only, ‘00000’. R/W 0016

7016 Interrupt Number. R/W 0016

7116 Interrupt Type. Bit 1 is read/write. Other bits are read only. R/W 0316

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

Index Mouse Conﬁguration Register or Action Type Reset

3016 Activate. See also bit 0 of the SIOCF1. When the Mouse of the KBC is inactive,

the IRQ selected by the Mouse Interrupt Number and Wake-Up on IRQ Enable

commands handling the PS/2 Mouse.

R/W 0016

7016 Mouse Interrupt Number and Wake-Up on IRQ Enable register. R/W 0C16

7116 Mouse Interrupt Type. Bit 1 is read/write; other bits are read only. R/W 0316

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

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Table 58. Keyboard Conﬁguration Registers

6.1.11 Shared Memory Configuration

Logical Device 15 (0F16) (Shared Memory) Conﬁguration

Table 59 lists the configuration registers that affect the shared memory functional block. The shared memory base address

registerspointtothesharedmemoryregistersdescribedinSection 5.3onpage 297.Thememoryspacetowhich the shared

memory responds is defined by the configuration registers in the following sections. See “Standard Logical Device Config-

uration Register Definitions” on page 337 and Section 6.1.2 on page 340 for a detailed description of the other configuration

registers.

Table 59. Shared Memory Conﬁguration Registers

Index Keyboard Conﬁguration Register or Action Type Reset

3016 Activate. See also bit 0 of the SIOCF1. R/W 0016

6016 Base Address MSB register. Bits 7-3 (for A15-11) are read only, ‘00000’. R/W 0016

6116 Base Address LSB register. Bits 2-0 are read only, ‘000’. R/W 6016

6216 Command Base Address MSB register. Bits 7-3 (for A15-11) are read only,

‘00000’. R/W 0016

6316 Command Base Address LSB. Bits 2-0 are read only, ‘100’. R/W 6416

7016 KBD Interrupt Number and Wake-Up on IRQ Enable register. R/W 0116

7116 KBD Interrupt Type. Bit 1 is read/write; other bits are read only. R/W 0316

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

Index Conﬁguration Register or Action Type Reset

3016 Activate. When bit 0 is cleared, the registers of this logical device are not

accessible. R/W 0016

6016 Base Address MSB register. R/W 0016

6116 Base Address LSB register. Bits 3-0 (for A3-A0) are read only, ‘0000’. R/W 0016

7016 No interrupt assignment. RO 0016

7116 No interrupt assignment. RO 0016

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

F416 Shared Memory Conﬁguration register. R/W 0016 or 0916, de-

pending on the

value of the

SHBM strap input

F516 Shared Memory Base Address High Byte register. R/W 0016

F616 Shared Memory Base Address Low Byte register. R/W 0016

F716 Shared Memory Size Conﬁguration register. R/W 0016

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Memory Range Programing

LPC memory transactions and/or LPC-FWH transactions can be forwarded to the PC87591x shared memory. The Shared

Memory Configuration register defines the transaction type and address range to which the PC87591x responds. The SHBM

strap inputs affect the default settings of the Shared Memory Configuration register to enable boot process from shared

memories. Two memory areas may be individually enabled: a user-defined zone and BIOS memory (either BIOS-LPC

and/or BIOS-FWH spaces).

To enable BIOS support, set the SHBM strap inputs to select any of the BIOS modes (see Section 2.3 on page 53 for de-

tails). The PC87591x responds to LPC memory read and write transactions to/from the BIOS address spaces, shown in

Table 60, as long as BIOS LPC Enable (bit 0) of the Shared Memory Configuration register is set.

Table 60. BIOS-LPC Memory Space Deﬁnition

The PC87591x responds to LPC-FWH read and write transactions to/from the high memory address range (’386’ mode

BIOS range), shown in Table 60, as long as BIOS FWH Enable (bit 3) of the Shared Memory Configuration register is set.

Table 61. BIOS-FWH Memory Space Deﬁnition

On host domain hardware reset in BIOS mode, the BIOS LPC Enable bit is set and the BIOS FWH Enable bit is set. The

PC87591x automatically detects the type of host boot protocol in use, via the first completed BIOS read operation after host

domain hardware reset. If the first read is an LPC memory read, the BIOS FWH Enable bit is cleared. If the first read is an

LPC-FWH read, the BIOS LPC Enable bit is cleared. Any other LPC or LPC-FWH transactions are ignored. The bits are

cleared only by the first read operation, allowing software to enable responding to these address ranges by setting the bit.

Figure 112 illustrates this behavior.

Figure 112. BIOS Mapping Enable Scheme

Theuser-definedsharedmemoryenablessharingthememorywithout using it as a shared BIOS memory. The memory base

address in the host address space and the size of the shared memory are defined in the Shared Memory Base and Shared

Memory Size registers. Address bits above the block size are ignored and are internally replaced with 1s for the purpose of

address translation (e.g., for a 2 Mbyte block size, A21 through A31 are replaced with 1s).

Memory Address Range Description

000E 000016 - 000E FFFF16 Extended BIOS range (Legacy); only when Extended

BIOS Enable bit in Shared Memory Range Configuration

000F 000016 - 000F FFFF16 BIOS Range (Legacy)

FFE0 000016 - FFFF FFFF16 386 mode BIOS range; this is the upper 2 Mbytes of the

memory space.

Memory Address Range Description

FFE0 000016 - FFFF FFFF16 386 mode BIOS range; this is the upper 2 Mbytes of the

memory space. The PC87591x uses the first 21 address

lines and ID field to identify FWH access to the shared

memory.

Note: Only hardware-controlled transitions are shown;

other transitions are possible via software writes to the bits.

BIOS FWH Enable = 1

BIOS LPC Enable = 1

BIOS FWH Enable = 1

BIOS LPC Enable = 0

BIOS FWH Enable = 0

BIOS LPC Enable = 1

BIOS FWH Enable = 0

BIOS LPC Enable = 0

First LPC FWH Read

Host Domain [SHBM = 0] Shared Disable BIOS

[SHBM = 1] Enable BIOS

First LPC Memory Read

Hardware Reset

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Shared Memory Conﬁguration Register

This register is reset on host domain hardware reset to 0016 or 0916, depending on the value of the SHBM strap input.

Location: Index F416

Type: R/W

Shared Memory Base Address High Byte Register

This register describes the high byte for the user-defined memory zone mapped to the shared memory (decoded as bits 31

to 24 of the 32-bit address range, bits 15-0 are 0). This register is reset to 0016 on Host Domain Hardware reset.

Location: Index F516

Type: R/W

Bit 76543210

Name

BIOS FWH ID BIOS FWH

Enable

User-

Defined

Memory

Space

Enable

BIOS

Extended

Space

Enable

BIOS LPC

Enable

Reset 0000Strap00Strap

Bit Description

0BIOS LPC Enable. Enables the PC87591x to respond to LPC memory accesses to the BIOS-LPC space. The

reset value of this register is deﬁned by the SHBM conﬁguration inputs. The value of this bit is updated later,

based on the detected host BIOS scheme; see “Memory Range Programing” on page 350 for details.

0: Disabled (default when SHBM disable BIOS configuration)

1: Enabled (default when SHBM enable BIOS configuration)

1BIOS Extended Space Enable. Expands the BIOS address space to which the PC87591x responds to include

the Extended BIOS address range.

0: Disabled (default)

1: Enabled

2User-Defined Memory Space Enable. When set, enables the PC87591x to respond to LPC memory read and

write accesses in the user-deﬁned memory area range. The base address and size of the user-deﬁned range

are speciﬁed by the Shared Memory Base Address High and Low Byte registers and the Shared Memory Size

Conﬁguration register.

0: Disabled (default)

1: Enabled

3BIOS FWH Enable. When set, enables PC87591x response to LPC-FWH transactions to the BIOS-FWH

space. The reset value of this register is deﬁned by the XCNF(2-0) conﬁguration inputs. The value of this bit is

later updated based on the detected host BIOS scheme; see “Memory Range Programing” on page 350 for

details.

0: Disabled (default when SHBM disable BIOS configuration)

1: Enabled (default when SHBM enable BIOS configuration)

7-4 BIOS FWH ID. These four bits correspond to the identiﬁcation nibble, which is part of a FWH transaction (see

Section 6.1.7 for details).

Bit 76543210

Name User-Deﬁned Memory Zone Address High

Reset 00000000

Bit Description

7-0 User-Deﬁned Memory Zone Address High. Deﬁnes the higher eight bits of the user-deﬁned memory block

base address. The base address should be aligned on the selected block size.

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Shared Memory Base Address Low Byte Register

This register describes the low byte for the user-defined memory zone mapped to the shared memory (decoded as bits 23

to 16 of the 32-bit address range, bits 15-0 are 0). This register is reset to 0016 on Host Domain Hardware reset.

Location: Index F616

Type: R/W

Shared Memory Size Conﬁguration Register

This register defines the size of the user-defined memory zone mapped to the shared memory. This register is reset to 0016

on host domain hardware reset.

Location: Index F716

Type: R/W

Bit 76543210

Name User-Deﬁned Memory Zone Address Low

Reset 00000000

Bit Description

7-0 User-Deﬁned Memory Zone Address Low. Deﬁnes the lower eight bits of the user-deﬁned memory block base

address. The base address should be aligned on the selected block size.

Bit 76543210

Name Reserved User-Defined Memory Zone Size

Reset 00000000

Bit Description

3-0 User-Deﬁned Memory Zone Size. Deﬁnes the size, in bytes, of the zone window. The size is deﬁned as an

exponent of two, using the equation: NumOfBytes = 2n(where, n = User-Deﬁned Memory Zone size+16). The

zone must always be aligned to the window size (i.e., for a 128 Kbyte window, the 17 LSBs of the address

should be zero).

Bits

3 2 1 0 Size (Bytes)

0 0 0 0 64K (default)

. . .

0 1 0 1 2M

Other Reserved

7-4 Reserved.

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6.1.12 Real Time Clock (RTC) Configuration

Logical Device 16 (1016) RTC Conﬁguration

Table 62 lists the configuration registers that affect the RTC. See Section 6.1.1 on page 335 and Section 6.1.2 on page 340

for descriptions of the other configuration registers.

Table 62. RTC Conﬁguration Registers

RAM Lock Register (RLR)

When a non-reserved bit is set to 1, it can be cleared only by host domain hardware reset.

Location: Index F016

Type: R/W

Index RTC Conﬁguration Register or Action Type Reset

3016 Activate. When bit 0 is cleared, the registers of this logical device are not

accessible. R/W 0016

6016 Base Address MSB register. R/W 0016

6116 Base Address LSB register. Bit 0 (for A0) is read only, ‘0’. R/W 7016

6216 Base Address MSB register. R/W 0016

6316 Base Address LSB register. Bit 0 (for A0) is read only, ‘0’. R/W 7216

7016 RTC Interrupt Number and Wake-Up on IRQ Enable register. R/W 0816

7116 RTC Interrupt Type. Bit 1 is read/write; other bits are read only. R/W 0016

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

F016 RAM Lock Register (RLR) R/W 0016

F116 Date of Month Alarm Register Offset (DOMAO) R/W 0016

F216 Month Alarm Register Offset (MONAO) R/W 0016

F316 Century Register Offset (CENO) R/W 0016

Bit 76543210

Name Block

Standard

RAM

Block RAM

Write

Block

Extended

RAM Write

Block

Extended

RAM Read

Block

Extended

RAM Reserved

Reset 00000000

Bit Description

2-0 Reserved.

3Block Extended RAM. Controls access to the Extended RAM 128 bytes.

0: No effect on Extended RAM access (default)

1: Reads and writes to the Extended RAM are blocked, writes are ignored and reads return FF16

4Block Extended RAM Read. Controls read from bytes 0016-1F16 of the Extended RAM.

0: No effect on Extended RAM access (default)

1: Reads to bytes 0016-1F16 of the Extended RAM are ignored; reads return FF16

5Block Extended RAM Write. Controls writes to bytes 0016-1F16 of the Extended RAM.

0: No effect on the Extended RAM access (default)

1: Writes to bytes 0016-1F16 of the Extended RAM are ignored

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Date Of Month Alarm Register Offset (DOMAO)

Location: Index F116

Type: R/W

Month Alarm Register Offset (MONAO)

Location: Index F216

Type: R/W

Century Register Offset (CENO)

Location: Index F316

Type: R/W

6Block RAM Write.

0: No effect on RAM access (default)

1: Writes to RAM (Standard and Extended) are ignored

7Block Standard RAM.

0: No effect on Standard RAM access (default)

1: Reads and writes to locations 3816-3F16 of the Standard RAM are blocked, writes are ignored and reads return

FF16

Bit 76543210

Name Reserved Date of Month Alarm Register Offset Value

Reset 00000000

Bit Description

6-0 Date of Month Alarm Register Offset Value.

7Reserved.

Bit 76543210

Name Reserved Month Alarm Register Offset Value

Reset 00000000

Bit Description

6-0 Month Alarm Register Offset Value.

7Reserved.

Bit 76543210

Name Reserved Century Register Offset Value

Reset 00000000

Bit Description

6-0 Century Register Offset Value.

7Reserved.

Bit Description

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6.1.13 Power Management Interface Channel 1 Configuration

Logical Device 17 (1116) Power Management Channel 1

●Table 63 lists the configuration registers that affect Power Management I/F Channel 1

See “Standard Logical Device Configuration Register Definitions” on page 337 and Section 6.1.2 on page 340 for descrip-

tions of the other configuration registers.

Table 63. Power Management Conﬁguration Registers

6.1.14 Power Management Interface Channel 2 Configuration

Logical Device 18 (1216) Power Management Channel 2

Table 64 lists the configuration registers that affect Power Management I/F Channel 2. See Section 6.1.2 on page 340 for

descriptions of the other configuration registers.

Table 64. Power Management Conﬁguration Registers

Index Power Management Channel 1 Conﬁguration Register or Action Type Reset

3016 Activate. See also bit 0 of the SIOCF1. R/W 0016

6016 Data Register Base Address MSB register. Bits 7-3 (for A15-11) are read only,

‘00000’. R/W 0016

6116 Data Register Base Address LSB register. R/W 6216

6216 Command/Status Base Address MSB register. Bits 7-3 (for A15-11) are read

only, ‘00000’. R/W 0016

6316 Command/Status Base Address LSB. R/W 6616

7016 PM Interrupt Number and Wake-Up on IRQ Enable register. R/W 0116

7116 PM Interrupt Type. Bit 1 is read/write; other bits are read only. R/W 0316

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

Index Power Management 2 Conﬁguration Register or Action Type Reset

3016 Activate. See also bit 0 of the SIOCF1. R/W 0016

6016 Data Register Base Address MSB register. Bits 7-3 (for A15-11) are read only,

‘00000‘. R/W 0016

6116 Data Register Base Address LSB register. R/W 6816

6216 Command/Status Base Address MSB register. Bits 7-3 (for A15-11) are read

only, ‘00000’. R/W 0016

6316 Command/Status Base Address LSB. R/W 6C16

7016 PM Interrupt Number and Wake-Up on IRQ Enable register. R/W 0116

7116 PM Interrupt Type. Bit 1 is read/write; other bits are read only. R/W 0316

7416 Report no DMA assignment. RO 0416

7516 Report no DMA assignment. RO 0416

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6.2 REAL-TIME CLOCK (RTC)

The RTC provides timekeeping and calendar management capabilities. It uses a 32.768 KHz signal as the basic clock for

timekeeping. The RTC also includes 242 bytes of battery-backed RAM for general-purpose use.

The RTC provides the following functions:

●Accurate timekeeping and calendar management

●Alarm at a predetermined time and/or date

●Three programmable interrupt sources

●Valid timekeeping during power-down, by utilizing external battery backup

●242 bytes of battery-backed RAM

●RAM lock schemes to protect its content

●Internal oscillator circuit (the crystal itself is off-chip) or external clock supply for the 32.768 KHz clock

●A century counter

●PnP support:

—Relocatable index and data registers

—Module access enable/disable option

—Host interrupt enable/disable option

●Additional low-power features such as:

—Automatic switching from battery to VCC

—Internal power monitoring on the VRT bit

—Oscillator disabling to save battery during storage

●Software compatible with the DS1287 and MC146818

6.2.1 Bus Interface

The RTC function is initially mapped to the default SuperI/O locations at indexes 7016 to 7316 (two Index/Data pairs). These

locations may be reassigned in compliance with Plug and Play requirements.

6.2.2 RTC Clock Generation

The RTC uses a 32.768 KHz clock signal as the basic clock for timekeeping. The 32.768 KHz clock is generated by the in-

ternal oscillator circuit or by an external oscillator (see Sections 6.2.3 and 6.2.4).

6.2.3 Internal Oscillator

The internal oscillator employs an external crystal connected to the on-chip amplifier. The on-chip amplifier is accessible on

the 32KX1 input pin and the 32KX2 output pin. See Figure 113 for the recommended external circuit and Table 65 for a list-

ing of the circuit components. The oscillator may be disabled in certain conditions. See Section 6.2.12 on page 362 for more

details.

Figure 113. Recommended Oscillator External Circuitry

VBAT

CF Internal

External

32KX1 / 32KX2

C1 C2

To other

modules

Battery

CF = 0.1 µF

32KCLKIN

Host-Controlled Modules and Host Interface (Continued)

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Table 65. Crystal Oscillator Circuit Components

External Elements

Choose C1 and C2 capacitors (see Figure 113) to match the crystal’s load capacitance. The load capacitance CL“seen” by

crystal Y is comprised of C1in series with C2and in parallel with the parasitic capacitance of the circuit. The parasitic ca-

pacitance is caused by the chip package, board layout and socket (if any), and can vary from 0 to 8 pF. The rule of thumb

for choosing these capacitors is:

CL = (C1 * C2) / (C1 + C2) + CPARASITIC

Oscillator Start-Up

The oscillator starts to generate 32.768 KHz pulses to the RTC after approximately t32KW from when VBAT is higher than

VBATMIN (2.4 V) or from when VCC is higher than VCCMIN (3.0V).

C1can be trimmed to achieve precisely 32.768 KHz. To achieve a high time accuracy, use crystal and capacitors with low

tolerance and temperature coefficients.

6.2.4 External Oscillator

32.768 KHz can be applied from an external clock source, as shown in Figure 114.

Figure 114. External Oscillator Connections

Connections

Connect the clock to the 32KCLKIN pin, leaving the oscillator output, 32KX2, unconnected.

Component Parameters Values Tolerance

Crystal Resonance Frequency 32.768 KHz Parallel Mode User deﬁned

Type N-Cut or XY-bar

Serial Resistance 40 KΩMax

Quality Factor, Q 35000 Min

Shunt Capacitance 2 pF Max

Load Capacitance, CL9-13 pF

Temperature Coefﬁcient User deﬁned

Resistor R1Resistance 20 MΩ5%

Resistor R2Resistance 121 KΩ5%

Capacitor C1Capacitance 10 pF 10%

Capacitor C2Capacitance 12 pF 10%

32.768 KHz

Clock Generator

Internal

External

32KCLKIN / 32KX2

To other

modules

Battery

VBAT

OUT

POWER

CF = 0.1 µF

32KX1

Host-Controlled Modules and Host Interface (Continued)

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Signal Parameters

The signal levels should conform to the voltage level requirements for 32KCLKIN/32KX1, stated in Section 7 on page 372.

The signal should have a duty cycle of approximately 50%. To oscillate during power-down, it should be sourced from a

battery-backed source. This guarantees that the RTC delivers updated time/calendar information.

6.2.5 Timing Generation

The timing generation function divides the 32.768 KHz clock by 215 to derive a 1 Hz signal, which serves as the input for the

seconds counter. This is performed by a divider chain composed of 15 divide-by-two latches, as shown in Figure 115.

Figure 115. Divider Chain Control

Bits 6-4 (DV2-0) of CRA register control the following functions:

●Normal operation of the divider chain (counting)

●Divider chain reset to 0

●Oscillator activity when only VBAT power is present (backup state).

The divider chain can be activated by setting normal operational mode (bits 6-4 of CRA = 0102). The first update occurs

500 ms after divider chain activation.

Bits 3-0 of CRA register select one the of 15 taps from the divider chain to be used as a periodic interrupt. The periodic flag

becomes active after half of the programed period has elapsed, following divider chain activation.

See “RTC Control Register A (CRA)” on page 367 for more details.

6.2.6 Timekeeping

Data Format

Time is kept in BCD or binary format, as determined by bit 2 (DM) of Control Register B (CRB), and in either 12 or 24-hour

format, as determined by bit 1 of this register.

Note: When changing the above formats, re-initialize all the time registers.

Daylight Saving

Daylight saving time exceptions are handled automatically, as described in the RTC Control Register B (CRB) in

Section 6.2.15 on page 363.

Leap Years

Leap year exceptions are handled automatically by the internal calendar function. Every four years, February is extended to

29 days. Year 2000 is a leap year.

32.768 KHz

13 2

14 2

15 1Hz

Divider Chain

DV2 DV1 DV0

CRA Register

Oscillator

Enable

32KX1 / 32KX2

To other

Reset

654

modules

32KCLKIN

Host-Controlled Modules and Host Interface (Continued)

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6.2.7 Updating

The time and calendar registers are updated once per second regardless of bit 7 (SET) of CRB register. Since the time and

calendar registers are updated serially, unpredictable results may occur if they are accessed during the update. Therefore,

it is essential to ensure that reading or writing to the time storage locations does not coincide with a system update of these

locations. There are several methods to avoid this contention.

Method 1

1. Set bit 7 of CRB register to 1. This takes a “snapshot” of the internal time registers and loads them into the user copy

registers. The user copy registers are seen when accessing the RTC from outside and are part of the double buffering

mechanism. This bit may be kept set for up to 1 second, since the time/calendar chain continues to be updated once per

second.

2. Read or write the required registers (since bit 1 is set, the access is to the user copy registers). If a read operation is

performed, the information read is correct from the time bit 1 was set. If a write operation is performed, the write is only

to the user copy registers.

3. Reset bit 1 to 0. During the transition, the user copy registers update the internal registers, using the double buffering

mechanism to ensure that the update is performed between two time updates. This mechanism enables new time pa-

rameters to be loaded in the RTC.

Method 2

1. Access the RTC registers after detection of an Update Ended interrupt. This implies that an update has just been com-

pleted, and 999 ms remain until the next update.

2. To detect an Update Ended interrupt, do one of the following:

—Poll bit 4 of CRC register.

—Use the following interrupt routine:

a. Set bit 4 of CRB register.

b. Wait for an interrupt from interrupt pin.

c. Clear the IRQF flag of CRC register before exiting the interrupt routine.

Method 3

Poll bit 7 of CRA register. The update occurs 244 µs after this bit goes high. Therefore, if a 0 is read, the time registers remain

stable for at least 244 µs.

Method 4

Use a periodic interrupt routine to determine if an update cycle is in progress, as follows:

1. Set the periodic interrupt to the desired period.

2. Set bit 6 of CRB register to enable the interrupt from periodic interrupt.

3. Wait for the periodic interrupt to occur. This indicates that the period represented by the following expression remains

until another update occurs:

[(Period of periodic interrupt / 2) + 244 µs]

6.2.8 Alarms

The timekeeping function can be set to generate an alarm when the current time reaches a stored alarm time. After each

RTC time update (every 1 second), the seconds, minutes, hours, date of month and month counters are compared with their

corresponding registers in the alarm settings. If equal, bit 5 of CRC register is set. Bit 5 of CRC is sent to the MSWC as an

alarm signal. If the Alarm Interrupt Enable bit was previously set (bit 5 of CRB register), interrupt request pin is also active.

Any alarm register may be set to “Unconditional Match” by setting bits 7-6 to ‘11’. This combination, not used by any BCD

or binary time codes, results in a periodic alarm. The rate of this periodic alarm is determined by the registers that were set

to “Unconditional Match”.

For example, if all but the seconds and minutes alarm registers are set to “Unconditional Match”, an interrupt is generated

every hour at the specified minute and second. If all but the seconds, minutes and hours alarm registers are set to “Uncon-

ditional Match”, an interrupt is generated every day at the specified hour, minute and second.

Host-Controlled Modules and Host Interface (Continued)

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PC87591E/S/L

6.2.9 Power Supply

The PC87591x is supplied from four supply voltages, as shown in Figure 116 (see Section 3.1 on page 62 for more detailed

description):

●System power supply voltage, VDD

●System analog power supply voltage, AVCC

●System standby power supply voltage, VCC

●Backup voltage, from low-capacity Lithium battery

A standby voltage (VCC) from the external AC/DC power supply powers the RTC under normal conditions.

Figure 116. Power Supply Connections

Figure 117 shows a typical battery configuration. No external diode is required to meet the UL standard, because of the in-

ternal switch and internal serial resistor RUL.

Figure 117. Typical Battery Conﬁguration

RTC power is supplied from either VCC or VBAT voltage source, according to the sources’ levels. An internal voltage com-

parator delivers the control signals to a pair of switches. When VCC is active, the RTC power is drawn from it. Battery backup

voltage (VBAT) maintains the correct time and saves the CMOS memory when the VCC voltage is absent due to power failure

or disconnection of the main battery. Figure 117 illustrates the mechanism whereby VCC or VBAT is selected.

To assure that the module uses power from VCC and not from VBAT, the VCC voltage should be maintained above its

minimum (VCC2PP), as detailed in Section 7 on page 372. Figure 118 illustrates the switching between VCC (thick green

line) and VBAT (thin red line) and vice-versa for generating VPP (thin blue line).

The actual voltage point where the PC87591x switches from VBAT to VCC is lower than the minimum workable battery volt-

age but high enough to guarantee the correct functionality of the oscillator and the CMOS RAM.

The Valid RAM and Timer bit (VRT) in CRD register indicates the state of non-interrupted power supplied to the

PC87591x RTC module. VRT is cleared once VPP power is lost, i.e., when VCC and VBAT are both below VLOWBAT. The

host code should read this bit as part of the startup routine, before using the timer or the CMOS-RAM contents. In case

a value of 0 is read, the RAM and timer must be initialized before use. The VRT bit is set once read.

RTC

Power

Backup

VDD

VCC

VDD

VCC

VBAT Battery

External AC Power

Supply

VDD Sense

VCC

VBAT

VCC

PC0

VBAT

ONCTL ONCTL

ACPI Controller

AVCC

VBAT

0.1 µF

VCC

BT1

0.1 µF

VPP

RUL

VREF

RTC

1. Place a 0.1 µF capacitor on each VCC power supply

pin as close as possible to the pin, and also on VBAT.

2. Place a 10-47 µF capacitor on the common power

supply net as close as possible to the device.

Host-Controlled Modules and Host Interface (Continued)

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Figure 119 shows typical battery current consumption during battery-backed operation; Figure 120 shows typical battery

current consumption during normal operation.

Figure 119. Typical Battery Current During Battery-Backed Power Mode

Figure 120. Typical Battery Current During Normal Operation Mode

6.2.10 System Bus Lockout

During power on or power off, spurious bus transactions from the host may occur. To protect the RTC internal registers from

corruption, all inputs are automatically locked out. The lockout condition is asserted when VCC is lower than VCCON.

6.2.11 Power-Up Detection

When system power is restored after a power failure or power off state (VCC=0), the lockout condition continues for a delay

of 62 ms (minimum) to 125 ms (maximum) after the RTC switches from battery to system power.

The lockout condition is switched off immediately in the following situations:

●If the Divider Chain Control bits, DV0-2, (bits 6-4 in CRA register) specify a normal operation mode (0102), all input

signals are enabled immediately on detection of system voltage above VCCON.

●When battery voltage is below VBATDCT and host domain hardware reset is active, all input signals are enabled im-

mediately on detection of system voltage above VCCON. This also initializes registers at offsets 0016 through 0D16.

●If bit 7 (VRT) of CRD register is 0, all input signals are enabled immediately on detection of system voltage above VCCON.

time

VPP

VBAT

3.3V - 3.6V

VCC2PP

VPP2CC

VPP uses VCC VPP uses VBAT

Figure 118. VPP Generation Using VCC or VBAT

VPP

VBAT

VPP uses VBAT

IBAT (µA)

1.0

0.9

0.8

0.7

2.4 3.0 3.6 VBAT (V)

IBAT (µA)

0.20

0.15

0.10

0.05

3.0 3.3 3.6 VCC

Note: Battery voltage in this test is 3.0V.

(V)

Host-Controlled Modules and Host Interface (Continued)

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6.2.12 Oscillator Activity

The RTC oscillator is active if:

●VCC power supply is higher than VCCON, independent of the battery voltage, VBAT.

●VBAT power supply is higher than VBATMIN whether or not VCC is present.

The RTC oscillator is disabled in the following cases:

●During power-down (VBAT only), if the battery voltage drops below VBATMIN, the PC87591x may enter Battery Fail

state. In this case, the oscillator may stop oscillating and memory contents may be corrupted or lost.

●Software wrote 00X to DV2-0 bits of CRA register and VCC is removed. This disables the oscillator and decreases

the power consumption from the battery connected to the VBAT pin. When disabling the oscillator, the CMOS RAM is

not affected as long as the battery is present at a correct voltage level.

If the RTC oscillator becomes inactive, the following features are dysfunctional/disabled:

●Timekeeping

●Periodic interrupt

●Alarm

6.2.13 Interrupt Handling

The RTC has a single Interrupt Request line, which handles the following three interrupt conditions:

●Periodic interrupt

●Alarm interrupt

●Update end interrupt

The interrupts are generated if the respective enable bits in CRB register are set prior to an interrupt event occurrence.

Reading the CRC register clears all interrupt flags. Therefore, when multiple interrupts are enabled, the interrupt service

routine should first read and store the CRC register and then deal with all pending interrupts by referring to this stored status.

If an interrupt is not serviced before a second occurrence of the same interrupt condition, the second interrupt event is lost.

Figure 121 illustrates the interrupt timing in the RTC.

Figure 121. Interrupt/Status Timing

Flags (and IRQ) are reset at the conclusion of CRC read

or by reset.

A = Update In Progress bit high before

update occurs = 244 µs

B = Periodic interrupt to update

= Period (periodic int) / 2 + 244 µs

C = Update to Alarm Interrupt = 30.5 µs

P = Period is programed by RS3-0 of CRA

Bit 7

Bit 4

Bit 6

Bit 5

of CRA

of CRC

P/2 P/2

244 µs

30.5 µs

Host-Controlled Modules and Host Interface (Continued)

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6.2.14 Battery-Backed RAMs and Registers

The RTC has two battery-backed RAMs and 17 registers, used by the logical units themselves. Battery-backup power en-

ables information retention during system power down.

The RAMs are:

●Standard RAM

●Extended RAM

The memory maps and register content of the RAMs are shown in Section 6.2.18 on page 371 and illustrated in Figure 122.

The first 14 bytes and three programmable bytes of the Standard RAM are overlaid by time, alarm data and control registers.

The remaining 111 bytes are general-purpose memory.

Registers with reserved bits should be written using the “Read-Modify-Write” method.

All register locations within the device are accessed by the RTC Index and Data registers (at base address and base ad-

dress+1, as defined by RTC configuration registers at index 6016 and 6116). The Index register points to the register location

being accessed, and the Data register contains the data to be transferred to or from the location. An additional 128 bytes of

battery-backed RAM (also called Extended RAM) may be accessed via a second pair of Index and Data registers (at base

address and base address+1, as defined by RTC configuration registers in index 6216 and 6316).

Access to the two RAMs may be locked. For details, see ”RAM Lock Register (RLR)” in Section 6.1.12 on page 353.

The index of three of the RTC registers is programmable using registers in the RTC logical device bank (part of the SuperI/O

configuration registers). If enabled, these registers override three of the Standard RAM locations; see Section 6.1.12 on

page 353.

6.2.15 RTC Registers

The RTC registers can be accessed at any time during normal operation mode; i.e., when VCC is within the recommended

operation range. This access is disabled during battery-backed operation. Write operation to these registers is also disabled

if bit 7 of CRD register is 0.

Note: Before attempting to perform any start-up procedures, read the explanation of bit 7 (VRT) of CRD register.

See Section 6.2.18 on page 371 for a detailed description of the memory map for the RTC registers.

This section describes the RTC Timing and Control registers, which control basic RTC functionality.

For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.

0016

0D16

7F16

0E16

Registers

Standard RAM

(3-byte override by

0016

7F16

Index Data

SIO Configuration Extended Bank

(Legacy 0x72, 0x73)

Standard Bank

(Legacy 0x70, 0x71)

Index Data

6016

6316

7F16

7016

7316 prog. indexes

RAM lock

programmable indexes)

}

Base Base+1

Index Data

Base Base+1

Figure 122. RTC Module Registers Mapping

Host-Controlled Modules and Host Interface (Continued)

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RTC Register Map

Seconds Register (SEC)

Location: Index 0016

Type: R/W

Index Mnemonic Name Type Reset

0016 SEC Seconds Register R/W VPP PUR

0116 SECA Seconds Alarm Register R/W VPP PUR

0216 MIN Minutes Register R/W VPP PUR

0316 MINA Minutes Alarm Register R/W VPP PUR

0416 HOR Hours Register R/W VPP PUR

0516 HORA Hours Alarm Register R/W VPP PUR

0616 DOW Day Of Week Register R/W VPP PUR

0716 DOM Date Of Month Register R/W VPP PUR

0816 MON Month Register R/W VPP PUR

0916 YER Year Register R/W VPP PUR

0A16 CRA RTC Control Register A R/W Bit speciﬁc

0B16 CRB RTC Control Register B R/W Bit speciﬁc

0C16 CRC RTC Control Register C R/O Bit speciﬁc

0D16 CRD RTC Control Register D R/O VPP PUR

Programmable1

1. Overlaid on RAM bytes in range 0E16-7F16.

DOMA Date of Month Alarm Register R/W VPP PUR

Programmable1MONA Month Alarm Register R/W VPP PUR

Programmable1CEN Century Register R/W VPP PUR

Bit 76543210

Name Seconds Data

Reset 00000000

Bit Description

7-0 Seconds Data. Values may be 00 to 59 in BCD format or 00 to 3B in binary format.

Host-Controlled Modules and Host Interface (Continued)

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Seconds Alarm Register (SECA)

Location: Index 0116

Type: R/W

Minutes Register (MIN)

Location: Index 0216

Type: R/W

Minutes Alarm Register (MINA)

Location: Index 0316

Type: R/W

Hours Register (HOR)

Location: Index 0416

Type: R/W

Bit 76543210

Name Seconds Alarm Data

Reset 00000000

Bit Description

7-0 Seconds Alarm Data. Values may be 00 to 59 in BCD format or 00 to 3B in binary format.

When bits 7 and 6 are both set to one (“11”), unconditional match is selected.

Bit 76543210

Name Minutes Data

Reset 00000000

Bit Description

7-0 Minutes Data. Values may be 00 to 59 in BCD format or 00 to 3B in binary format.

Bit 76543210

Name Minutes Alarm Data

Reset 00000000

Bit Description

7-0 Minutes Alarm Data. Values may be 00 to 59 in BCD format or 00 to 3B in binary format.

When bits 7 and 6 are both set to one (“11”), unconditional match is selected.

Bit 76543210

Name Hours Data

Reset 00000000

Bit Description

7-0 Hours Data. For 12-hour mode, values may be 01 to 12 (a.m.) and 81 to 92 (p.m.) in BCD format or 01 to 0C

(a.m.) and 81 to 8C (p.m.) in binary format. For 24-hour mode, values may be 00 to 23 in BCD format or 00 to

17 in binary format.

Host-Controlled Modules and Host Interface (Continued)

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Hours Alarm Register (HORA)

Location: Index 0516

Type: R/W

Day Of Week Register (DOW)

Location: Index 0616

Type: R/W

Date Of Month Register (DOM)

Location: Index 0716

Type: R/W

Month Register (MON)

Location: Index 0816

Type: R/W

Bit 76543210

Name Hours Alarm Data

Reset 00000000

Bit Description

7-0 Hours Alarm Data. For 12-hour mode, values may be 01 to 12 (a.m.) and 81 to 92 (p.m.) in BCD format or 01

to 0C (a.m.) and 81 to 8C (p.m.) in binary format. For 24-hour mode, values may be 00 to 23 in BCD format or

00 to 17 in binary format.

When bits 7 and 6 are both set to one (“11”), unconditional match is selected.

Bit 76543210

Name Day Of Week Data

Reset 00000000

Bit Description

7-0 Day Of Week Data. Values may be 01 to 07 in BCD format or 01 to 07 in binary format.

Bit 76543210

Name Date Of Month Data

Reset 00000000

Bit Description

7-0 Date Of Month Data. Values may be 01 to 31 in BCD format or 01 to 1F in binary format.

Bit 76543210

Name Month Data

Reset 00000000

Bit Description

7-0 Month Data. Values may be 01 to 12 in BCD format or 01 to 0C in binary format.

Host-Controlled Modules and Host Interface (Continued)

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Year Register (YER)

Location: Index FF16

Type: R/W

RTC Control Register A (CRA)

This register controls test selection, among other functions and cannot be written before reading bit 7 of the CRD register.

Location: Index 0A16

Type: R/W

Table 66. Divider Chain Control and Test Selection

Bit 76543210

Name Year Data

Reset 00000000

Bit Description

7-0 Year Data. Values may be 00 to 99 in BCD format or 00 to 63 in binary format.

Bit 76543210

Name Update in

Progress Divider Chain Control 2-0 Periodic Interrupt Rate Select 3-0

Reset 00100000

Bit Description

3-0 Periodic Interrupt Rate Select. These R/W bits select one of 15 output taps from the clock divider chain to

control the rate of the periodic interrupt (see Table 67 on page 368 and Figure 115 on page 358). They are

cleared to 0002as long as bit 7 of CRD register is 0.

6-4 Divider Chain Control. These R/W bits control the conﬁguration of the divider chain for timing generation and

7Update in Progress. This RO bit is not affected by reset; it is 0 when bit 7 of CRB register is 1.

0: Timing registers not updated within 244 µs

1: Timing registers updated within 244 µs

DV2 DV1 DV0 Conﬁguration

CRA6 CRA5 CRA4

0 0 X Oscillator Disabled

0 1 0 Normal Operation

011Test

10X

1 1 X Divider Chain Reset

Host-Controlled Modules and Host Interface (Continued)

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RTC Control Register B (CRB)

Location: Index 0B16

Type: R/W

Table 67. Periodic Interrupt Rate Encoding

Rate Select

3210 Periodic Interrupt

Rate (ms) Divider Chain

Output

0 0 0 0 No interrupts -

0 0 0 1 3.906250 7

0 0 1 0 7.812500 8

0 0 1 1 0.122070 2

0 1 0 0 0.244141 3

0 1 0 1 0.488281 4

0 1 1 0 0.976562 5

0 1 1 1 1.953125 6

1 0 0 0 3.906250 7

1 0 0 1 7.812500 8

1 0 1 0 15.625000 9

1 0 1 1 31.250000 10

1 1 0 0 62.500000 11

1 1 0 1 125.000000 12

1 1 1 0 250.000000 13

1 1 1 1 500.000000 14

Bit 76543210

Name

Set Mode Periodic

Interrupt

Enable

Alarm

Interrupt

Enable

Update

Ended

Interrupt

Enable

Reserved Data Mode Hour Mode Daylight

Savings

Reset 00000000

Bit Description

0Daylight Savings. This bit is reset at VPP Power-Up reset only.

0: Disabled

1: Enabled

In the spring, time advances from 1:59:59 AM to 3:00:00 AM on the first Sunday in April.

In the fall, time returns from 1:59:59 AM to 1:00:00 AM on the last Sunday in October.

1Hour Mode. This bit is reset at VPP Power-Up reset only.

0: 12-hour format enabled

1: 24-hour format enabled

2Data Mode. This bit is reset at VPP Power-Up reset only.

0: BCD format enabled

1: Binary format enabled

Host-Controlled Modules and Host Interface (Continued)

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RTC Control Register C (CRC)

Location: Index 0C16

Type: RO

3Reserved. This bit is deﬁned as “Square Wave Enable” by MC146818 and is not supported by the RTC. It is

always read as 0.

4Update Ended Interrupt Enable. This interrupt is generated when an update occurs. It is cleared to 0 on RTC

reset (i.e., host domain reset) or when the RTC is disabled.

0: Disabled

1: Enabled

5Alarm Interrupt Enable. This interrupt is generated immediately after a time update in which the seconds,

minutes, hours, date and month time equal their respective alarm counterparts. It is cleared to 0 as long as bit

7 of CRD register is 0.

0: Disabled

1: Enabled

6Periodic Interrupt Enable. Bits 3-0 of CRA register determine the rate at which this interrupt is generated. It is

cleared to 0 on RTC reset (i.e., host domain reset) or when RTC is disabled.

0: Disabled

1: Enabled

7Set Mode. This bit is reset at VPP Power-Up reset only.

0: Timing updates occur normally

1: User copy of time is “frozen”, allowing the time registers to be accessed whether or not an update occurs

Bit 76543210

Name

IRQF Periodic

Interrupt

Flag

Alarm

Interrupt

Flag

Update

Ended

Interrupt

Flag

Reserved

Reset 00000000

Bit Description

3-0 Reserved.

4Update Ended Interrupt Flag. This RO bit is cleared to 0 on RTC reset (i.e., host domain reset) or when the

RTC is disabled. In addition, this bit is cleared to 0 when this register is read.

0: No update occurred since the last read

1: Time registers update

5Alarm Interrupt Flag. This RO bit is cleared to 0 as long as bit 7 of CRD register is 0. In addition, this bit is

cleared to 0 when this register is read.

0: No alarm detected since the last read

1: Alarm condition detected

6Periodic Interrupt Flag. This RO bit is cleared to 0 on RTC reset (i.e., host domain reset) or when the RTC is

disabled. In addition, this bit is cleared to 0 when this register is read.

0: No transition occurred on the selected tap since the last read

1: Transition occurred on the selected tap of the divider chain

7IRQF (IRQ Flag). This RO bit mirrors the value of the interrupt output signal. When interrupt is active, IRQF is

1. To clear this bit (and deactivate the interrupt), read CRC register; this clears ﬂags UF, AF and PF, which

results in IRQF being cleared, as well.

0: IRQ inactive

1: Logic equation is true: ((UIE and UF) or (AIE and AF) or (PIE and PF))

Bit Description

Host-Controlled Modules and Host Interface (Continued)

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RTC Control Register D (CRD)

Location: Index 0D16

Type: RO

Date of Month Alarm Register (DOMA)

Location: Programmable Index

Type: R/W

Month Alarm Register (MONA)

Location: Programmable Index

Type: R/W

Bit 76543210

Name Valid RAM

and Time Reserved

Reset 00000000

Bit Description

6-0 Reserved.

7Valid RAM and Time. This bit senses the voltage that feeds the RTC (VCC or VBAT) and indicates whether or

not it was too low since the last time this bit was read. If it was too low (i.e., < VLOWBAT), the RTC contents

(time/calendar registers and CMOS RAM) are not valid. This bit is set after the CRD is read.

0: The voltage that feeds the RTC was too low

1: RTC contents (time/calendar registers and CMOS RAM) valid

Bit 76543210

Name Date of Month Alarm Data

Reset 11000000

Bit Description

7-0 Date of Month Alarm Data. Values may be 01 to 31 in BCD format or 01 to 1F in binary format.

When bits 7 and 6 are both set to one (“11”), unconditional match is selected (default).

Bit 76543210

Name Month Alarm Data

Reset 11000000

Bit Description

7-0 Month Alarm Data. Values may be 01 to 12 in BCD format or 01 to 0C in binary format.

When bits 7 and 6 are both set to one (“11”), unconditional match is selected (default).

Host-Controlled Modules and Host Interface (Continued)

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Century Register (CEN)

Location: Programmable Index

Type: R/W

6.2.16 BCD and Binary Formats

6.2.17 Usage Hints

1. Read bit 7 of CRD register at each system power-up to validate the contents of the RTC registers and the CMOS RAM.

When this bit is 0, the contents of these registers and the CMOS RAM are questionable. This bit is reset when the backup

battery voltage is too low. The voltage level at which this bit is reset is below the minimum recommended battery voltage,

2.4V. Although the RTC oscillator may function properly and the register contents may be correct at lower than 2.4V, this

bit is reset since correct functionality cannot be guaranteed. System BIOS may use a checksum method to revalidate

the contents of the CMOS-RAM. The checksum byte should be stored in the same CMOS RAM.

2. Change the backup battery while normal operating power is present, and not in backup mode, to maintain valid time and

3. A rechargeable NiCd battery may be used instead of a non-rechargeable Lithium battery. This is the preferred solution

for portable systems, where small components are essential.

4. A supercap capacitor may be used instead of the normal Lithium battery. In a portable system, typically, the VSB voltage

is always present because the power management stops the system before its voltage falls to low. A supercap capacitor

in the range of 0.047F-0.47F should be able to supply the power during a battery replacement.

6.2.18 RTC General-Purpose RAM Map

Table 68. Standard RAM Map

Table 69. Extended RAM Map

Bit 76543210

Name Century Data

Reset 00000000

Bit Description

7-0 Century Data. Values may be 00 to 99 in BCD format or 00 to 63 in binary format.

Parameter BCD Format Binary Format

Seconds 00 to 59 00 to 3B

Minutes 00 to 59 00 to 3B

Hours 12-hour mode:01 to 12 (a.m.); 81 to 92 (p.m.)

24-hour mode:00 to 23 12-hour mode:01 to 0C (a.m.); 81 to 8C (p.m.)

24-hour mode:00 to 17

Day 01 to 07 (Sunday = 01) 01 to 07

Date 01 to 31 01 to 1F

Month 01 to 12 (January = 01) 01 to 0C

Year 00 to 99 00 to 63

Century 00 to 99 00 to 63

Index Description

0E16 -7F

161

1. Battery-backed 111-byte RAM (114 − 3 overlaid registers).

Battery-backed general-purpose 111-byte RAM.

Index Description

0016 -7F

16 Battery-backed general-purpose 128-byte RAM.

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PC87591E/S/L

7.0 Device Speciﬁcations

This section provides the power and grounding guidelines for the PC87591x, specifies the device’s maximum ratings and

electrical characteristics and describes its timing.

7.1 GENERAL DC ELECTRICAL CHARACTERISTICS

7.1.1 Recommended Operating Conditions

7.1.2 Absolute Maximum Ratings

If military- or aerospace-specified devices are required, please contact a National Semiconductor sales office or distributor

for availability and specifications.

Storage Temperature: −65°C to +150°C

Temperature Under Bias: 0°C to +70°C

Absolute maximum ratings are values beyond which damage to the device may occur. Unless otherwise specified, all volt-

ages are relative to ground.

Symbol Parameter Min Typ Max Unit

VDD Host Domain Supply Voltage 3.0 3.3 3.6 V

VCC Core Domain Supply Voltage 3.0 3.3 3.6 V

AVCC Analog Supply Voltage 3.15 3.3 3.45 V

VBAT Battery Backup Supply Voltage 2.4 3.6 V

TAOperating Temperature 0 +70 °C

Symbol Parameter Conditions Min Max Unit

VDD Host Domain Supply Voltage −0.5 +4.2 V

VCC Core Domain Supply Voltage −0.5 +4.2 V

AVCC Analog Supply Voltage −0.5 +4.2 V

VBAT Battery Backup Supply Voltage −0.5 +4.2 V

VIInput Voltage All other buffer types −0.5 5.5 V

Buffer types: INAC1,IN

AD,IN

DI,IN

OSC,

INPCI,IN

TS (IOPE0-3, IOPE6-7)

1. When ACM is enabled.

−0.5 VSUP2+ 0.5

2. VSUP is VDD, VCC, AVCC or VBAT, according to the power well of the input.

VOOutput Voltage All other buffer types −0.5 5.5 V

Buffer types: ODA,O

DI,O

OSC,O

PCI −0.5 VSUP3+ 0.5

3. VSUP is VDD, VCC, AVCC or VBAT, according to the power well of the output.

TSTG Storage Temperature −65 +165 °C

PDPower Dissipation 1W

TLLead Temperature Soldering (10 s) +260 °C

ESD Tolerance CZAP = 100 pF

RZAP = 1.5 KΩ4

4. Value based on test complying with RAI-5-048-RA human body model ESD testing.

2000 V

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.1.3 Capacitance

7.1.4 Power Supply Current Consumption under Recommended Operating Conditions

7.1.5 Voltage Thresholds

Symbol Parameter Min2Typ1

1. TA = 25°C; f = 1 MHz.

Max2

2. Not tested; guaranteed by characterization.

Unit

CIN Input Pin Capacitance 5 7 pF

CIN1 Clock Input Capacitance 5 8 12 pF

CIO I/O Pin Capacitance 10 12 pF

COOutput Pin Capacitance 6 8 pF

Symbol Parameter Conditions1

1. All parameters speciﬁed for 0°C≤ TA≤ 70°C; VDD and VCC = 3.3V ±10% unless otherwise speciﬁed.

Typ Max Unit

IDD VDD Average Main Supply Current VIL = 0.5V, VIH = 2.4V

No Load 23mA

IDDLP VDD Quiescent Main Supply Current in Low

Power Mode VIL = GND, VIH =V

No Load 30 50 µA

ICC VCC Active Supply Current tCLK = 250 ns 15 mA

tCLK =50ns 23 30 mA

ICCW VCC Active Executing WAIT Supply Current tCLK = 250 ns 6.6 mA

tCLK =50ns 10 mA

ICCI VCC Idle Mode Supply Current Idle Mode

VIL = GND, VIH =V

No Load

15 µA

IBAT VBAT Battery Supply Current Power Off Mode 0.9 1.5 µA

Symbol Parameter Conditions1

1. All parameters speciﬁed for 0°C≤ TA≤ 70°C.

Min Typ Max Unit

VCCON VCC Detected as Power-On 2.5 2.95 V

VCC2PP VCC detected for use as source for VPP 2.3 2.4 V

VPP2CC VCC detected inactive for use of VBAT as

source for VPP

1.9 2.2 V

VDDON VDD Detected as on 2.5 2.95 V

VBATDTC Battery Detected 1.0 1.2 V

VLOWBAT Low Battery Voltage 1.3 1.9 V

VBATMIN Workable Battery Voltage 2.4 V

VBATMAX Battery Input Voltage 3.6 V

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.2 DC CHARACTERISTICS OF PINS BY I/O BUFFER TYPES

The following tables summarize the DC characteristics of all device pins described in Chapter 2 on page 39. The character-

istics describe the general I/O buffer types defined in Table 4 on page 41. For exceptions, see Section 7.2.9 on page 376.

For the DC characteristics of the analog pins, see Section 7.4 on page 378. The DC characteristics of the system interface

meet the PCI 2.1 3.3V DC signaling.

7.2.1 Input, CMOS Compatible with Schmitt Trigger

Symbol: INCS

7.2.2 Input, PCI 3.3V

Symbol: INPCI

7.2.3 Input, SMBus Compatible

Symbol: INSM

Symbol Parameter Conditions Min Max Unit

VIH Input High Voltage 0.75 VSUP1

1. VSUP is VDD or VCC, according to the power well of the input.

5.52

2. Not tested; guaranteed by design.

VIL Input Low Voltage −0.521.1 V

VHInput Hysteresis 5003

3. Not tested; guaranteed by characterization.

IIL Input Leakage Current 0 < VIN <V

SUP ±14

4. Maximum 10 µA for all pins together.

µA

Symbol Parameter Conditions Min Max Unit

VIH Input High Voltage 0.5 VDD VDD + 0.51

1. Not tested; guaranteed by design.

VIL Input Low Voltage −0.510.3 VDD V

lIL2

2. Input leakage current includes the output leakage of the bidirectional buffers with TRI-STATE outputs.

Input Leakage Current 0 < VIN <V

DD ±13

3. Maximum 10 µA for all pins together.

µA

Symbol Parameter Conditions Min Max Unit

VIH Input High Voltage 1.4 5.51

1. Not tested; guaranteed by design.

VIL Input Low Voltage −0.5 10.8 V

IIL2

2. Input leakage current includes the output leakage of the bidirectional buffers with TRI-STATE outputs.

Input Leakage Current 0 < VIN <V

DD ±13

3. Maximum 10 µA for all pins together.

µA

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.2.4 Input, TTL Compatible

Symbol: INT

7.2.5 Input, TTL Compatible with Schmitt Trigger

Symbol: INTS

7.2.6 Output, TTL Compatible Push-Pull Buffer

Symbol: Op/n

Output, TTL-compatible, rail-to-rail push-pull buffer that is capable of sourcing pmA and sinking n mA

Symbol Parameter Conditions Min Max Unit

VIH Input High Voltage 2.0 5.51

1. Not tested; guaranteed by design.

VIL Input Low Voltage −0.510.8 V

IIL2

2. Input leakage current includes the output leakage of the bidirectional buffers with TRI-STATE outputs.

Input Leakage Current 0 < VIN <V

CC ±13

3. Maximum 10 µA for all pins together.

µA

Symbol Parameter Conditions Min Max Unit

VIH Input High Voltage, 5V tolerant pins1

1. See Section 7.1.2 on page 372.

2.0 5.52

2. Not tested; guaranteed by design.

Input High Voltage, pins without 5V tolerance12.0 VSUP3+0.52

3. VSUP is VDD or VCC, according to the power well of the input.

VIL Input Low Voltage −0.520.8 V

VHInput Hysteresis 2504

4. Not tested; guaranteed by characterization.

IIL Input Leakage Current 0 < VIN <V

SUP ±15

5. Maximum 10 µA for all pins together.

µA

Symbol Parameter Conditions Min Max Unit

VOH Output High Voltage IOH =−pmA 2.4 V

IOH =−50 µAVSUP1−

0.2

1. VSUP is VDD or VCC, according to the power well of the input.

VOL Output Low Voltage IOL =nmA 0.4 V

IOL =50µA 0.2 V

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.2.7 Output, Open-Drain Buffer

Symbol: ODn

Output, TTL-compatible open-drain output buffer, capable of sinking nmA. Output from these signals is open-drain and

is never forced high.

7.2.8 Output, PCI 3.3V

Symbol: OPCI I

7.2.9 Exceptions

1. All pins are back-drive protected, except for output pins with PCI buffer type (INPCI or OPCI), oscillator (OOSC) and all

analog type pins (ODA and ODI).

2. The following pins have an internal static pull-up resistor and therefore may have leakage current to VCC (when VIN = 0):

SCL1-2, SDA1-2, IOPA7-0, IOPB7-0, IOPC7-0, IOPD7-0, IOPE7-4, IOPF7-0, KBSIN0-7, PSCLK1-4, PSDAT1-4.

3. Thefollowingstrappinshaveaninternalstaticpull-downresistorenabledduringPower-Upresetandthereforemayhave

leakage current to VSS (when VIN = VSUP): BADDR1-0, ENV1-0, SHBM, TRIS.

4. IOH is valid for a GPIO pin only when it is not configured as open-drain.

7.2.10 Terminology

Back-Drive Protection. Apin that is back-drive protected does not sink currentinto the supply when an input voltage higher

than the supply, but below the pin’s maximum input voltage, is applied to the pin. This is true even when the supply is inac-

tive. Note that active pull-up resistors and active output buffers are typically not back-drive protected.

5-Volt Tolerance. An input signal that is 5V tolerant can operate with input voltage of up to 5V even though the supply to

the device is only 3.3V. The actual maximum input voltage allowed to be supplied to the pin is indicated by the maximum

high voltage allowed for the input buffer. Note that some pins have multiple buffers, not all of which are 5V tolerant. In such

cases, there is a note that indicates at what conditions a 5V input may be applied to the pin; if there is no note, the low max-

imum voltage among the buffers is the maximum voltage allowed for the pin.

Symbol Parameter Conditions Min Max Unit

VOL Output Low Voltage IOL =nmA 0.4 V

IOL =50µA 0.2 V

Symbol Parameter Conditions Min Max Unit

VOH Output High Voltage lout =−500 µA 0.9 VDD V

VOL Output Low Voltage lout = 1500 µA 0.1 VDD V

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.3 INTERNAL RESISTORS

DC Test Conditions

Notes:

1. The equivalent resistance of the pull-up resistor is calculated by RPU = (VSUP − VPIN) / IPU.

2. The equivalent resistance of the pull-down resistor is calculated by RPD = VPIN / IPD.

7.3.1 Pull-Up Resistor

Symbol: PUnn

7.3.2 Pull-Down Resistor

Symbol: PDnn

Symbol Parameter Conditions Typical Min Max Unit

RPU1

1. Not tested; guaranteed by characterization.

Pull-up equivalent resistance VPIN =0V nn nn – 34% nn + 47% KΩ

VPIN = 0.17 VDD nn – 44% KΩ

VPIN = 0.8 VDD nn – 41% KΩ

Symbol Parameter Conditions Typical Min Max Unit

RPD1

1. Not tested; guaranteed by characterization.

Pull-down equivalent resistance VPIN =V

DD nn nn – 35% nn + 60% KΩ

VPIN = 0.17 VDD nn – 37% KΩ

VPIN = 0.8 VDD nn – 48% KΩ

Device

Under

Test RPU

Pull-Up Resistor Test Circuit Pull-Down Resistor Test Circuit

VSUP

Pin A

IPU

VPIN

Device

Under

Test

RPD

VSUP

Pin A

IPD

VPIN

VSUP

Figure 123. Internal Resistor Test Conditions, TA=0°Cto70°C, VSUP = 3.3V

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.4 ANALOG CHARACTERISTICS

7.4.1 ADC Characteristics

Voltage Measurement

Parameter Symbol Conditions1Min Typ Max Unit

Resolution RES 10 Bit

Offset Error2OERL3AD0-9:

12 mV ≤VIN ≤0.9 V ±0.25 LSB

OERHAD0-9:

40 mV ≤VIN ≤AVCC −0.8 ±0.25 LSB

OERBAD13:

0.9V ≤VIN ≤AVCC −0.2 ±0.25 LSB

OERVAD10-12:

0.1V ≤VIN ≤VFS ±0.25 LSB

Gain Error4GERLAD0-9:

12 mV ≤VIN ≤0.9 V ±0.75 LSB

GERHAD0-9:

40 mV ≤VIN ≤AVCC −0.8 ±0.75 LSB

GERBAD13:

0.9V ≤VIN ≤AVCC −0.2 ±0.75 LSB

GERVAD10-12:

0.1V ≤VIN ≤VFS ±0.75 LSB

Integral Non-linearity Error5INLLAD0-9:

12 mV ≤VIN ≤0.9 V ±0.5 LSB

INLHAD0-9:

40 mV ≤VIN ≤AVCC −0.8 ±0.5 LSB

INLBAD13:

0.9V ≤VIN ≤AVCC −0.2 ±0.5 LSB

INLVAD10-12:

0.1V ≤VIN ≤VFS ±0.5 LSB

Differential Non-linearity Error6DNLLAD0-9:

12 mV ≤VIN ≤0.9 V ±0.257LSB

DNLHAD0-9:

40 mV ≤VIN ≤AVCC −0.8 ±0.257LSB

DNLBAD13:

0.9V ≤VIN ≤AVCC −0.2 ±0.257LSB

DNLVAD10-12:

0.1V ≤VIN ≤VFS ±0.257LSB

External Inputs Accuracy8EACULAD0-9:

12 mV ≤VIN ≤0.9 V ±1 LSB

EACUHAD0-9:

40 mV ≤VIN ≤AVCC −0.8 ±1 LSB

7.0 Device Specifications (Continued)

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PC87591E/S/L

Internal Inputs Accuracy8, 9 IACUBAD13:

0.9V ≤VIN ≤AVCC −0.2 ±2 LSB

IACUVAD10-12:

0.1V ≤VIN ≤VFS ±2 LSB

Full Scale Voltage VFSL AD0-9 Low Scale 1.000 V

VFSH AD0-9 High Scale 3.000 V

VFSB AD13 4.000 V

VFSV AD10-12 4.000 V

Input Voltage Range VIN Note10 0AV

CC V

Analog Input Leakage Current IAL AD0-9: 0 ≤VIN ≤AVCC ±1µA

Analog Input Resistance RAIN AD0-9, AD13 4 ΜΩ

Analog Input Capacitance CAIN TBD pF

ADC Clock Frequency FCLK 0.5 MHz

ADC Enable Delay11 tEND 100 µs

Voltage Conversion Duration tVC 8.2 ms

1. All parameters speciﬁed for 0°C≤ TA≤ 70°C and AVCC= 3.3V ±5% unless otherwise speciﬁed.

2. The difference between 0V and the actual voltage value for code 00016.

3. XXXL = Inputs AD0-9, Low Scale; XXXH = Inputs AD0-9, High Scale; XXXV = Inputs AD10-12;

XXXB = Input AD13.

4. The difference between 1023/1024 * VFS and the actual voltage for code 3FF16.

5. The maximum difference between the ideal (straight) conversion line and the actual conversion curve, not

including the offset, gain and quantization (±0.5 LSB) errors.

6. The maximum difference between an ideal step size (1 LSB) and any actual step size.

7. No missing codes.

8. Total unadjusted error (includes the offset, gain, integral non-linearity and quantization (±0.5 LSB) errors).

9. The internal power supply inputs: VDD, VCC, AVCC.

10. Input Voltage allowed in normal operation. Linear range is as deﬁned for the different measurement modes.

11. Time from the moment when ADCEN=1 in ADCCNF register until the beginning of the “ADC cycle”.

Parameter Symbol Conditions1Min Typ Max Unit

7.0 Device Specifications (Continued)

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PC87591E/S/L

Temperature Measurement

7.4.2 ACM Characteristics

Parameter Symbol Conditions1

1. All parameters speciﬁed for 0°C≤ TA≤ 70°C and AVCC= 3.3V ±5% unless otherwise speciﬁed.

Min Typ Max Unit

Resolution RESB 8 Bit

RESC 1 oC

Accuracy Using Remote Diode2

2. See “Remote Diode Selection” on page 187.

RAC1 TA= +40°C to +100°C±3oC

RAC2 TA=−40°C to +125°C±5oC

Accuracy Using Local Diode LAC1 TA= +40°C to +100°C±1oC

LAC2 TA=−40°C to +125°C±3oC

Voltage at DN VDN 8µA≤ID≤120 µA 0.7 V

DP Source Current IDPH High Level 80 120 µA

IDPL Low Level 8 12 µA

Temperature Input Capacitance CTIN TBD pF

ADC Clock Frequency FCLK 0.5 MHz

ADC Enable Delay3

3. Time from the moment when ADCEN=1 in ADCCNF register until the beginning of the “ADC cycle”.

tEND 100 µs

Temperature Conversion Duration tTC 42 ms

Parameter Symbol Conditions1

1. All parameters speciﬁed for 0°C≤ TA≤ 70°C and VCC= 3.3V ±10% unless otherwise speciﬁed.

Min Typ Max Unit

Resolution RES 6 Bit

Differential Non-linearity Error2

2. The maximum difference between an ideal step size (1 LSB) and any actual step size.

DNL 0 ≤VIN ≤VCC ±0.53

3. No missing codes.

LSB

Accuracy (Total unadjusted error) ACU 0 ≤VIN ≤VCC ±1.5 LSB

Input Voltage Range VIN 0V

CC V

Analog Input Leakage Current IAL 0≤VIN ≤VCC ±1µA

Analog Input Capacitance CAIN TBD pF

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.4.3 DAC Characteristics

7.5 PACKAGE THERMAL INFORMATION

Thermal resistance (degrees C/W) ThetaJC and ThetaJA values for the various packages of the PC87591x are as follows:

Table 70. Theta (Θ) J Values

Airflow for ThetaJA values is measured in linear feet per minute (lfpm).

Parameter Symbol Conditions1

1. All parameters speciﬁed for 0°C≤ TA≤ 70°C. AVCC = 3.3V ± 5%, unless otherwise speciﬁed.

Min Typ Max Unit

Resolution RES 8 Bit

Offset Error2

2. The difference between 0V and the actual voltage value for code 0016.

OER AVCC = 3.3V ±1 LSB

Gain Error3

3. The difference between 255/256 * AVCC and the actual voltage for code FF16.

GER AVCC = 3.3V ±1 LSB

Integral Non-linearity Error4

4. The maximum difference between the ideal (straight) conversion line and the actual conversion curve, not

including the offset, gain and quantization (±0.5 LSB) errors.

INL AVCC = 3.3V,

0≤VOUT ≤AVCC

±0.5 LSB

Differential Non-linearity Error5

5. The maximum difference between an ideal step size (1 LSB) and any actual step size.

DNL AVCC = 3.3V,

0≤VOUT ≤AVCC

±0.56

6. Monotonic.

LSB

Output Voltage Range VOUT 0AV

CC V

Analog Output Resistance RS0≤VOUT ≤AVCC 234KΩ

Analog Output Capacitance CAO 10 15 pF

DAC Settling Time7

7. Time from the converter loading with data, to output voltage settling within an error of ±0.5 LSB.

TSET CL=50pF 1 µs

DAC Enable Delay8

8. Time from the moment when DACENn=1 in DACCTRL register until the settling of the output voltage.

TEND CL=50pF 10 µs

Package Type ThetaJA@0 lfpm ThetaJA@225 lfpm ThetaJA@500 lfpm ThetaJA@900 lfpm ThetaJC

128 LQFP 47.1 34.6 29.3 28.8 15.3

176 LQFP 39.8 32.3 29.5 26.2 5.1

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.6 AC ELECTRICAL CHARACTERISTICS

7.6.1 AC Test Conditions

Figure 124. AC Test Conditions, TA=0°Cto70°C, VSUP = 3.3V ±10%

Notes:

1. VSUP is VDD, VCC, AVCC or VBAT, according to the power well of the pin.

2. CL = 50 pF for all output pins (this value includes both jig and oscilloscope capacitance).

3. S1 = Open for push-pull output pins.

S1 = VSUP for high impedance to active low and active low to high impedance measurements.

S1 = VSS for high impedance to active high and active high to high impedance measurements.

RL = 1.0 KΩ

The following abbreviations are used in Section 7.6:

RE = Rising Edge

FE = Falling Edge

Deﬁnitions

The timing specifications in this section refer to low- or high-level voltage, according to the specific buffer type (TTL or

CMOS) on the rising or falling edges of all the signals, as illustrated in the following figures, unless specifically stated other-

wise.

Figure 125. CMOS Output Signals Speciﬁcation Conventions

Device

Under

Test

0.1 µf

Input Output

Load Circuit (Notes 1, 2, 3) AC Testing Input, Output Waveform

VSUP

2.4

0.4

2.0

0.8 Test Points 2.0

0.8

CLK

SIG1

SIG2

VOH, VOHhd

VOL, VOLhd

VOH, VOHhd

VOL, VOLhd

tSIG1v tSIG1a Vcc * 0.3

Vcc * 0.7

2.0V 2.40V

Vcc * 0.7

Vcc * 0.3

tSIG2h

tSIG1h

tSIG2v tSIG2a

or tSIG1ia

or tSIG2ia

7.0 Device Specifications (Continued)

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PC87591E/S/L

Figure 126. TTL: Input Signal Speciﬁcation Standard

Figure 127. CMOS with Hysteresis Inputs

Figure 128. Signal-to-Signal Delay

CLK

SIG1

SIG2

2.4V

0.4V

0.8V

2.0V

0.8V

2.0V

tSIG1s

setup tSIG1h

hold

tSIG2h

hold

tSIG2s

setup

VCHl VCHh

Vhys

2.4V

0.4V

0.8V

2.0V

2.4V

0.4V

0.8V

2.0V

SIG1

SIG2

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.6.2 Reset Timing

Figure 129. Internal Power-Up Reset

Notes:

1. Either WATCHDOG, Debugger I/F or Power-Up reset.

2. Valid on Power-Up reset only.

Figure 130. Warm Hardware Reset

Symbol Figure Description Reference Conditions Min Max Unit

tSUPUP 130 Supply wake-up time to

95% VCC After VCC >V

CCON 1ms

tIRST 130 Internal or power-on reset

time Power stable to end of 16th clock

cycle of CLK 16 *tCLK +

t32KD

16 *tCLK +

t32KD +t

32KW

tIPLv 130 Valid time: Internal strap

pull-up resistors Before end of 16th clock cycle of

CLK 16 *tCLK -

tEPLv 130 Valid time: External strap

pull-up resistors Before end of 16th clock cycle of

CLK 6*tCLK -

tWRST 130 RESET1-2 width RESET1-2 FE to RESET1-2 RE 3 *tCLK -

VCC (Power) 1

CLK

Internal Reset

tIRST

Internal Straps2

tIPLv

Internal

tSUPUP

0.95 VCC

VCCONmin

Reset Event 1

tEPLv

(Pull-down)

External Straps

(Pull-up)

Strap Sampling

Time

CLK

RESET1-2

tWRST

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.6.3 Clock Timing

Symbol Figure Description Reference Conditions Min Max Unit

Clock Input Timing

t32KCLKIN 131 Required clock period for

32KCLKIN From RE to RE of 32KCLKIN

t32NOM = 30.517578 30.5145

(t32NOM −

100ppm)

30.5206

(t32NOM +

100ppm)

µs

Clock Output Timing

tCLK 132 CLK period At 2.0V (both edges) 50 250 ns

tCLKh 132 CLK high time At 2.0V (both edges) 0.5 *tCLK −

5ns -

tCLKl 132 CLK low time At 0.8V (both edges) 0.5 *tCLK −

5ns -

tCLKr 132 CLK rise time 0.8V to 2.0V 6 ns

tCLKf 132 CLK fall time 2.0V to 0.8V 6 ns

tCLKw 133 CLK wake-up time From wake-up event until

CLK starts toggling 100 µs

tCLKINTst 133 tCLK period Active mode in steady state 0.99 *

tCLKINTnom1

1. tCLKINTnom is deﬁned in Table 36 on page 241.

1.01 *

tCLKINTnom

tCLKINTwk 133 tCLK period After wake-up from Idle 0.9 *

tCLKINTnom

1.1 *

tCLKINTnom

tCLKstab 133 tCLK stabilization time After wake-up from Idle 0.5 s

t32KW 131 32K oscillator wake-up time After VBAT >V

LOWBAT 1s

t32KD 132 CLK delay time After VCC >V

CCON 40 ms

Flash Operation Frequency

fFMAX Flash Section 0 and 1

maximal operation frequency

in Fast Read

CLK period 20 MHz

tFLPMAX Flash Section 0 and 1

maximal operation frequency

in Low Power

CLK period TBD MHz

7.0 Device Specifications (Continued)

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PC87591E/S/L

General

Figure 131. 32K Waveforms

32KX2

VBAT t32KW

VCC t32KD

CLK

32KX1/32KCLKIN

t32KCLKIN

7.0 Device Specifications (Continued)

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PC87591E/S/L

Figure 132. Clock Waveforms

Figure 133. Internal Clock Generator

tCLK

CLK

tCLKl

tCLKf tCLKr

Output Valid Output Hold

Output

Signal

Input

Signal

Input Setup Input Hold

Control

Signal 1

Control

Signal 2

tCLKh

Output Active Time

Wake-Up Event

tCLKINTwk tCLKINTst

tCLKstab

CLK

tCLKw

PC87591x in

Active Mode

PC87591x in

Idle Mode

7.0 Device Specifications (Continued)

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PC87591E/S/L

7.6.4 BIU Timing

Symbol Figure Description Reference Conditions Min Max Unit

BIU Input Timing

t1134, 136 to

138 Input setup time

D0-15 Before RE CLK 15 ns

t2134, 136 to

138 Input hold time

D0-15 After RE CLK 0 ns

BIU Output Timing

t3134 to 139 Output valid time

A0-17, BE0,1CBRD, D0-15 After RE CLK 14 ns

t4134 to 139 Output valid time

BST0-2 After RE CLK 0.5 *tCLK

+14ns -

t5134 to 138 Output active/inactive time

RD, SEL0-1, SELIO After RE CLK 14 ns

t6134, 135 Output active/inactive time

WR0-1 After RE CLK 0.5 *tCLK

+14ns -

t7136 Minimum inactive time

RD After RE RD tCLK −5ns -

t8134, 135 Output ﬂoat time

A0-17, D0-15,RD, SEL0-

1,SELIO,WR0-1

After RE CLK 14 ns

t9134, 135 Minimum delay time From RE RD to

D0-15 drive tCLK −8ns -

t10 135 Minimum delay time From RE RD to RE SELn 0 ns

t11 135 Minimum delay time From RE SELx to FE SELy0 ns

t12 134 to 139 Output hold time

A0-17, BE0-1, CBRD, D0-

15, RD, SEL0-1, SELIO

After RE CLK 0 ns

t13 134 to 139 Output hold time

BST0-2,WR0-1 After RE CLK 0.5 *tCLK

−4ns -

t14 135 D0-15 valid in late write

bus cycles Before RE WR0-1 (K + 0.5) *

tCLK −8ns -

7.0 Device Specifications (Continued)

Revision 1.07 389 www.national.com

PC87591E/S/L

Figure 134. Early Write Between Normal Read Bus Cycles

CLK

A0-18

SELx

SELy

WR0,1

D0-15

Normal Early Write Normal

T1 T2 T1 T2 T1 T2

Read Read

In Out In

BST0-2

t1t2

(y ≠x)

t3, t12

t5, t12 t5, t12

t5, t12

t5, t12 t5,

t12

t8,

t12

t6, t13 t6, t13

t4, t13 t4, t13

Idle

Cycle

7.0 Device Specifications (Continued)

www.national.com 390 Revision1.07

PC87591E/S/L

Figure 135. Late Write between Two Normal Read Bus Cycles, 0 Wait, AC Timing

Figure 136. Two Consecutive Normal Read Bus Cycles with Burst, 0 Wait, AC Timing

CLK

A0-18

SELx

D0-15

WR0-1

Normal Read Late Write

T1 T2 T1 T2 T1 T2

Bus State

In Out In

BST0-2

(x ≠y)

SELy

(y ≠x)

t10 t9

t11

Normal Read

t3, t12 t3, t12

t5, t12 t5, t12

t5, t12

t8, t12

t5, t12 t5, t12

t6, t13

t4, t13 t4, t13

t14

CLK

A0-18

SELx

SELy

WR0-1

D0-15

Normal Read Normal Read

T1 T2 T2B T1 T2B

In In In In

BST0-2

t2t2

(x ≠y)

(y ≠x)

t3t3, t12 t3, t12

t5, t12 t5, t12

t4, t13 t4, t13

7.0 Device Specifications (Continued)

Revision 1.07 391 www.national.com

PC87591E/S/L

Figure 137. Normal Read Bus Cycle (2 Internal Waits, and 1 Hold), AC Timing

Figure 138. Fast Read Bus Cycle, AC Timing

CLK

A0-18

SELn,

D0-15

WR0-1

Bus State T1 TIW TIW T2 Thold

BST0-2

t1t2

t4, t13

SELIO

t3, t12

t5, t12 t5, t12

t4, t13

CLK

A0-18

SELx

SELy

WR0-1

D0-15

Fast Late Write Fast

TIdle T1-2 T1 T2 T1-2 T1

Read Read

TIdle

In Out In

BST0-2

(x ≠y)

(y ≠x)

t4, t13 t4, t13

t3, t12

t5, t12 t5, t12

Idle

Cycle

7.0 Device Specifications (Continued)

www.national.com 392 Revision1.07

PC87591E/S/L

Figure 139. Core Bus Monitoring Bus Cycle, AC Timing

CLK

A0-12,

SEL0-1,

WR0-1

D0-15

DBE

BST0-2

SELIO

A16-18

CBRD

BE0-1

t4, t13

t3, t12

7.0 Device Specifications (Continued)

Revision 1.07 393 www.national.com

PC87591E/S/L

7.6.5 GPIO Ports Timing

Symbol Figure Description Reference Conditions Min Max Unit

GPIO Input Timing

tINPs 140 Input setup time IOPA0-7,

IOPB0-7, IOPC0-7, IOPD0-

7, IOPE0-7, IOPF0-7,

IOPG0-7, IOPH0-7, IOPI0-7,

IOPJ0-7, IOPK0-7, IOPL0-4,

IOPM0-7, KBSIN0-71

1. When using the Schmitt input.

Before RE CLK 0.5 *tCLK -

tINPh 140 Input hold time IOPA0-7,

IOPB0-7, IOPC0-7, IOPD0-

7, IOPE0-7, IOPF0-7,

IOPG0-7, IOPH0-7, IOPI0-7,

IOPJ0-7, IOPK0-7, IOPL0-4,

IOPM0-7, KBSIN0-71

After RE CLK 0 ns

GPIO Output Timing

tOUTv 141 Output valid time

KBSOUT0-15, IOPA0-7,

IOPB0-7, IOPC0-7, IOPD0-

7, IOPF0-7, IOPG0-7,

IOPH0-7, IOPI0-7, IOPJ0-7,

IOPK0-7, IOPL0-4, IOPM0-7

After RE CLK 0.5 *tCLK -

tOUTh 141 Output hold time KBSOUT0-

15, IOPA0-7, IOPB0-7,

IOPC0-7, IOPD0-7, IOPF0-

7, IOPG0-7, IOPH0-7,

IOPI0-7, IOPJ0-7, IOPK0-7,

IOPL0-4, IOPM0-7

After RE CLK 0 ns

CLK

Px Input Signals

tINPs tINPh

Data In

Py Input Signals

Pz Input Signals

Figure 140. Input Signal Timing for Input and I/O Port Signals

CLK

Px Output Signals

tOUTv

tOUTh

Data Out

Pw Output Signals

Pz Output Signals

Figure 141. Output Signal Timing for Output and I/O Port Signals

7.0 Device Specifications (Continued)

www.national.com 394 Revision1.07

PC87591E/S/L

7.6.6 PWM Timing

Figure 142. Output Signal Timing for PWM Signals

7.6.7 MSWC Timing

Figure 143. Wake-Up Timing

Symbol Figure Description Reference Conditions Min Max Unit

tOUTv 142 Output valid time After RE CLK 0.5 *tCLK -

tOUTh 142 Output hold time After RE CLK 0 ns

Symbol Figure Description Reference Conditions Min Max Unit

twupd 143 Wake-up propagation delay After FE RI2,1 30 ns

tL143 RI2,1 and RING Low Time 10 ns

tH143 RI2,1 and RING High Time 10 ns

CLK

PWM0-7

tOUTv

tOUTh

Data Out

RING, RI1, RI2

PWUREQ, SMI

twupd

tLtH

7.0 Device Specifications (Continued)

Revision 1.07 395 www.national.com

PC87591E/S/L

7.6.8 PS/2 Interface Timing

Figure 144. PS/2 Receive Timing

Symbol Figure Description Reference Conditions Min Max Unit

PS/2 Input Timing

tPSDIs 144 Input setup time PSDAT1-3 Before FE PSCLK1-3 0 ns

tPSDIh 144 Input hold time PSDAT1-3 After RE PSCLK1-3 0 ns

tPSCLKl 144 PSCLK1-3 low time At 0.8V (Both Edges) (n+1)tCLK1ns

1. ‘n’ is the number of clock cycles, as programed in the IDB ﬁeld. See “PS/2 Control Register (PSCON)” on

page 130.

tPSCLKh 144 PSCLK1-3 high time At 2.0V (Both Edges) (n+1)tCLK1ns -

PS/2 Output Timing

tPSDOv 145 Output valid time

PSDAT1-4 After FE PSCLK1-4 (n+ 6)*tCLK

+14

2ns

2. ‘n’ is deﬁned in “PS/2 Control Register (PSCON)” on page 130.

tPSDOh 145 Output hold time PSDAT1-4 After FE PSCLK1-4 0 ns

tPSCLKa 146 Output active time PSCLK1-4 After RE CLK 17 ns

tPSCLKia 146 Output inactive time

PSCLK1-4 After RE CLK 17 ns

PSDAT1-4

PSCLK1-4

tPSDIs

tPSCLKl

tPSDIh

tPSCLKh

7.0 Device Specifications (Continued)

www.national.com 396 Revision1.07

PC87591E/S/L

Figure 145. PS/2 Transmit Timing

Figure 146. PS/2 Clock Signal Pulled Low by PC87591x

7.6.9 ACCESS.bus Timing

Symbol Figure Description Reference Conditions Min Max Unit

ACB Input Timing

tBUFi 148 Bus free time between Stop

and Start condition tSCLhigho -

tCSTOsi 148 SCL setup time Before Stop condition 8 *tCLK −

tSCLri

tCSTRhi 148, 149 SCL hold time After Start condition 8 *tCLK −

tSCLri

tCSTRsi 149 SCL setup time Before Start condition 8 *tCLK −

tSCLri

tDHCsi 149 Data high setup time Before SCL RE 2 *tCLK -

tDLCsi 148 Data low setup time Before SCL RE 2 *tCLK -

tSCLﬁ 147 SCL signal fall time 300 ns

tSCLri 147 SCL signal rise time 1 µs

tSCLlowi 150 SCL low time After SCL FE 16 *tCLK -

PSDAT1-4

PSCLK1-4

tPSDOv

tPSCLKl tPSCLKh

tPSDOh

PSCLK1-4

CLK

tPSCLKa tPSCLKia

7.0 Device Specifications (Continued)

Revision 1.07 397 www.national.com

PC87591E/S/L

tSCLhighi 150 SCL high time After SCL RE 16 *tCLK -

tSDAri 147 SDA signal fall time 300 ns

tSDAﬁ 147 SDA signal rise time 1 µs

tSDAhi 150 SDA hold time After SCL FE 0 ns

tSDAsi 150 SDA setup time Before SCL RE 2 *tCLK -

ACB Output Timing

tSCLhigho 150 SCL high time After SCL RE K *tCLK −1

µs-

tSCLlowo 150 SCL low time After SCL FE K *tCLK −1

µs-

tBUFo 148 Bus free time between Stop

and Start condition tSCLhigho -

tCSTOso 148 SCL setup time Before Stop condition tSCLhigho -

tCSTRho 148, 149 SCL hold time After Start condition tSCLhigho -

tCSTRso 149 SCL setup time Before Start condition tSCLhigho -

tDHCso 149 Data high setup time Before SCL RE tSCLhigho

−tSDAro

tDLCso 148 Data low setup time Before SCL RE tSCLhigho

−tSDAfo

tSCLfo 147 SDA signal fall time 300 ns

tSCLro 147 SDA signal rise time See note1

tSDAfo 147 SDA signal fall time 300 ns

tSDAro 147 SDA signal rise time See note1-

tSDAho 150 SDA hold time After SCL FE 7 *tCLK −

tSCLfo

tSDAvo 150 SDA valid time After SCL FE 7 *tCLK +

tSDAro

1. Depends on the signal’s capacitance and the pull-up value. Must be less than 1 µs.

Symbol Figure Description Reference Conditions Min Max Unit

7.0 Device Specifications (Continued)

www.national.com 398 Revision1.07

PC87591E/S/L

In Figure 147 through Figure 150, an “o” is added to parameter names in the timing tables for output signals and an “i” for

input signals, as displayed in the preceding table:

Figure 147. ACB Signals (SDA and SCL) Rising Time and Falling Time

Figure 148. ACB Start and Stop Condition Timing

Figure 149. ACB Start Condition TIming

SDA1-2

tSDAro

0.7 VCC

0.3 VCC

tSDAfi

0.7 VCC

0.3 VCC

SCL1-2

tSCLri

0.7 VCC

0.3 VCC

tSCLfi

0.7 VCC

0.3 VCC

tSDAfo

tSDAri

tSCLro tSCLfo

SDA1-2

SCL1-2

tCSTOso tBUFo

tDLCso

tCSTRho

Start Condition

Stop Condition

tCSTOsi tBUFi tCSTRhi

tDLCsi

SDA 1-2

SCL 1-2

tCSTRso

tDHCso

Start Condition

tCSTRho

tCSTRhi

tCSTRsi

tDHCsi

7.0 Device Specifications (Continued)

Revision 1.07 399 www.national.com

PC87591E/S/L

Figure 150. ACB Data Bit Timing

7.6.10 MFT16 Timing

Figure 151. Multi-Function Timer (MFT16) Input Timing

Figure 152. Multi-Function Timer (MFT16) Output Timing

Symbol Figure Description Reference Conditions Min Max Unit

MFT16 Input Timing

tTABH 151 TA1-2/TB1-2 high time tCLK + 5 ns -

tTABL 151 TA1-2/TB1-2 low time tCLK + 5 ns -

Symbol Figure Description Reference Conditions Min Max Unit

tOUTv 152 Output valid time After RE CLK 0.5 *tCLK -

tOUTh 152 Output hold time After RE CLK 0 ns

SDA 1-2

SCL 1-2

tSCLhigho

tCSLlowo

tSDAho

tSDAvo tSDAsi

tSCLhighi

tCSLlowi

tSDAhi

TA1-2/TB1-2

tTABL tTABH

CLK

TA1-2

tOUTv

tOUTh

7.0 Device Specifications (Continued)

www.national.com 400 Revision1.07

PC87591E/S/L

7.6.11 ICU/Development Timing

Figure 153. Pipe Status Signal (PFS and PLI) Timing

Figure 154. Reset Out Signal Timing

Symbol Figure Description Reference Conditions Min Max Unit

ICU/Development Input Timing

tBRKLs 153 Input setup time for BRKL Before RE CLK 10 ns

tBRKLh 153 Input hold time for BRKL After RE CLK 0 ns

ICU/Development Output Timing

tPFSh 153 Output hold time

PFS, PLI After RE CLK 0.5 *tCLK −

6ns -

tPFSv 153 Output active/inactive time

PFS, PLI After RE CLK 0.5 *tCLK +

12 ns -

tRSTOd 154 Output delay time RSTO After RE Internal Reset 5 *tCLK -

tRSTOw 154 Output pulse width RSTOFEtoRERSTO3

*tCLK -

tRSTOs 154 Output inactive time RSTO Before FE Internal Reset 0 ns

CLK

tPFSv

PFS tPFSv

tPFSv

PLI

tPFSh

tPFSv

tPFSh

tBRKLs tBRKLh

BRKL_RSTO

Internal

Reset

Hi-Z Hi-Z

SELIO,

SEL0, SEL1

tRSTOd tRSTOw tRSTOs

7.0 Device Specifications (Continued)

Revision 1.07 401 www.national.com

PC87591E/S/L

7.6.12 Asynchronous Edge Detected Signals Timing

Figure 155. ISE, PFAIL, EXINTn and MIWU Input Signal Timing

Symbol Figure Description Reference Conditions Min Max Unit

tasw 155 Wake-up Input Width:

EXWINT20-24,

EXWINT(40,45-46)

KBSIN0-7, PFAIL

PSCLK1-4, PSDAT1-4,

SWIN

Pulse width that guarantees

detection on edge 15 ns

tis 155 Input setup time:

EXWINT20-24,

EXWINT(40,45-46, PFAIL,

PSCLK1-4, PSDAT1-4,

SWIN

See note1

1. All wake-ups are asynchronous. Meeting the setup and hold are required for repeatability of the wake cycle

only.

10 ns

tih 155 Input hold time:

EXWINT20-24,

EXWINT(40,45-46), PFAIL,

PSCLK1-4, PSDAT1-4,

SWIN

See note10ns

CLK

PFAIL tIh

tIs tasw

EXWINT20-24

SWIN

EXWINT45,46

PSCLK1-4

KBSIN0-7

PSDAT1-4

7.0 Device Specifications (Continued)

www.national.com 402 Revision1.07

PC87591E/S/L

7.6.13 Debugger Interface Timing

Figure 156. Debugger I/F Setup Time, Hold Time and Recovery Time

Figure 157. TCK Pulse Width

Symbol Figure Description Reference Conditions Min Max Unit

Debugger Interface Input Signals

tS156 TMS Setup Time Before RE TCK 7 ns

tH156 TMS Hold Time After RE TCK 2 ns

tS156 TDI Setup Time Before RE TCK 1 ns

tH156 TDI Hold Time After RE TCK 3.5 ns

tHW 157 TCK High Pulse Width 15 ns

tLW 157 TCK Low Pulse Width 5 ns

fMAX Maximum TCK Clock

Frequency 20 MHz

Tpu 129 Wait Time Power-Up to TCK tIRST1

1. See Section 7.6.2 on page 384.

Debugger Interface Output Signals

tPLH

tPLL

158 Propagation Delay TCK to

TDO After FE TCK 3

322

22 ns

tPLZ

tPHZ

160

159 Disable Time TCK to TDO 2

222

22 ns

tPZL

tPZH

160

159 Enable Time TCK to TDO 3

322

22 ns

tTINTh 161 TINT hld time After FE TCK 10 ns

tTINTv 161 TINT valid time After RE CLK 25 ns

TMS, TDI

TCK

1.5V

TCK LOW-HIGH-LOW PULSE

TCK HIGH-LOW-HIGH PULSE

tHW, tLW

1.5V

7.0 Device Specifications (Continued)

Revision 1.07 403 www.national.com

PC87591E/S/L

Figure 158. Debugger Interface Propagation Delay

Figure 159. TDO TRI-STATE Output High Enable and Disable Times

Figure 160. TDO TRI-STATE Output Low Enable and Disable Times

Figure 161. TINT Output Timing

TCK

tPLH, tPLL

TDO 1.5V

1.5V

TCK

TDO

tPZH

VOH

VOH −0.3V

tPHZ

1.5V

TCK

TDO

tPZL

VOL

VOL+0.3V

tPLZ

1.5V

TCK

TINT

CLK

VOL

VOL+0.3V

tTINTv tTINTh

7.0 Device Specifications (Continued)

www.national.com 404 Revision1.07

PC87591E/S/L

7.6.14 USART Timing

Figure 162. USART Asynchronous Mode Timing

Symbol Figure Description Reference Conditions Min Max Unit

tr162 CMOS output rise time. Note 1

1. Not tested; guaranteed by characterization.

6ns

tf162 CMOS output fall time. Note 16ns

tCOh2 163 Output hold (synchr. mode) After RE USCLK −(2tCLK

+10 ns) -

tCOv2 163 Output valid (synchr. mode) After RE USCLK 2tCLK

+10 ns -

tCOh 162 Output hold (synchr. mode) After RE USCLK −20 ns

tIs 162 Input setup time

(asynchr. mode) Before RE CLK 15 ns

tIh 162 Input hold time

(asynchr. mode) After RE CLK 0 ns

tCLKX 162 USCLK input period (synchr.

mode) 250 ns

tCLKh 162 USCLK input low time. 2tCLK -

tCLKl 162 USCLK input high time. 2tCLK -

tSIs 163 Input Setup time (synchr.

mode) Before FE USCLK (in)

in synchronous mode tCLK +

10 ns -

tSIh 163 Input Hold time (synchr.

mode) After FE USCLK (in)

in synchronous mode tCLK +

10 ns -

tSIs1 164 Input Setup time (synchr.

mode) Before FE USCLK (out)

in synchronous mode 20 ns

tSIh1 164 Input Hold time (synchr.

mode) After FE USCLK (out)

in synchronous mode 20 ns

CLK

121212121212

tIS

tIH

tCOv tCOv

Output Signals:

UTXD

USCLK

Input Signals:

URXD

USCLK (In)

7.0 Device Specifications (Continued)

Revision 1.07 405 www.national.com

PC87591E/S/L

Figure 163. USART Synchronous Mode Timing (USCLK Input)

Figure 164. USART Synchronous Mode Timing (USCLK Out)

Figure 165. USART Synchronous Mode Timing (USCLK)

USCLK (In)

UTXD

tCLKX

tCOh2

tSIs

tSIh

tCLKXh

tCLKXl

URXD

tCOv2

USCLK (Out)

tCOv3

tSIs1

tSIh1

UTXD

URXD

USCLK

URXD

tSIs1

tSIh1

7.0 Device Specifications (Continued)

www.national.com 406 Revision1.07

PC87591E/S/L

7.6.15 LCLK and RESET1-2

Figure 166. LCLK Waveform

Symbol Parameter Min Max Units

tCYC1

1. The PCI may have any clock frequency between nominal DC and 33 MHz. Device operational parameters at fre-

quencies under 16 MHz may be guaranteed by design rather than by testing. The clock frequency may be

changed at any time during the operation of the system as long as the clock edges remain “clean” (monotonic)

and the minimum cycle and high and low times are not violated. The clock may only be stopped in a low state.

LCLK Cycle Time 30 ns

tHIGH LCLK High Time 11 ns

tLOW LCLK Low Time 11 ns

-LCLK Slew Rate2

2. Rise and fall times are speciﬁed in terms of the edge rate measured in V/ns. This slew rate must be met across

the minimum peak-to-peak portion of the clock wavering as shown below.

1 4 V/ns

-RESET1-2 Slew Rate3

3. The minimum RESET1-2 slew rate applies only to the rising (de-assertion) edge of the reset signal, and ensures

that system noise cannot render an otherwise monotonic signal to appear to bounce in the switching range.

50 mV/ns

0.6 VDD

0.2 VDD

0.5 VDD

0.4 VDD

0.3 VDD

0.4 VDD P-to-P

(minimum)

tHIGH tLOW

tCYC

7.0 Device Specifications (Continued)

Revision 1.07 407 www.national.com

PC87591E/S/L

7.6.16 LPC and SERIRQ Signals

Figure 167. LPC/SERIRQ Interface Output Timing

Figure 168. LPC/SERIRQ Interface Input Timing

Symbol Figure Description Reference Conditions Min Max Unit

tVAL 167 Output Valid Delay After RE CLK 11 ns

tON 167 Float to Active Delay After RE CLK 2 ns

tOFF 167 Active to Float Delay After RE CLK 28 ns

tSU 168 Input Setup Time Before RE CLK 7 ns

tHI 168 Input Hold Time After RE CLK 0 ns

Leakage Only

0.285 VDD

0.615 VDD

0.4 VDD 0.4 VDD

LCLK

LAD3-LAD0,

LDRQ, SERIRQ

Outputs

tVAL

tON tOFF

VDD = 3.3V

tVAL

LAD3-LAD0,

SERIRQ Output Enabled

0.4 VDD

LCLK

LAD3-LAD0, LFRAME

RESET1-2,

LPCPD

, SERIRQ

Inputs

VDD = 3.3V

tHI

tSU

www.national.com 408 Revision1.07

PC87591E/S/L

A. Software for Hardware Interface

A.1 CORE DOMAIN REGISTER LIST

Module Register Name Size Register

Address Access Type Value After

Reset Comments

A.1.1 Module Conﬁguration

(Section 2.3 on page 53 and Section 2.4.2 on page 58)

EICFG Byte 00 FF0016 Read/Write 0016

IOEE1 Byte 00 FF0216 Read/Write 0016

IOEE2 Byte 00 FF0416 Read/Write 0016

MCFG Byte 00 FF1016 Read/Write 0016 or 8016

MCFGSH Byte 00 FBFE16 Write Only MCFG shadow

STRPST Byte 00 FF1216 Read Only According to

external straps

A.1.2 Bus Interface Unit (BIU)

(Section 4.1.10 on page 83)

BCFG Byte 00 F98016 Read/Write 0716

IOCFG Word 00 F98216 Read/Write 069F16

SZCFG0 Word 00 F98416 Read/Write 069F16

SZCFG1 Word 00 F98616 Read/Write 069F16

SZCFG2 Word 00 F98816 Read/Write 069F16

A.1.3 DMA Controller

(Section 4.2.8 on page 92)

ADCA0 Double W. 00 FA0016 Read/Write

ADRA0 Double W. 00 FA0416 Read/Write

ADCB0 Double W. 00 FA0816 Read/Write

ADRB0 Double W. 00 FA0C16 Read/Write

BLTC0 Double W. 00 FA1016 Read/Write

BLTR0 Double W. 00 FA1416 Read/Write

CNTL0 Word 00 FA1C16 Read/Write 000016

STAT0 Byte 00 FA1E16 Read/Write 0016

ADCA1 Double W. 00 FA2016 Read/Write

ADRA1 Double W. 00 FA2416 Read/Write

ADCB1 Double W. 00 FA2816 Read/Write

Software for Hardware Interface (Continued)

Revision 1.07 409 www.national.com

PC87591E/S/L

ADRB1 Double W. 00 FA2C16 Read/Write

BLTC1 Double W. 00 FA3016 Read/Write

BLTR1 Double W. 00 FA3416 Read/Write

CNTL1 Word 00 FA3C16 Read/Write 000016

STAT1 Byte 00 FA3E16 Read Only 0016

ADCA2 Double W. 00 FA4016 Read/Write

ADRA2 Double W. 00 FA4416 Read/Write

ADCB2 Double W. 00 FA4816 Read/Write

ADRB2 Double W. 00 FA4C16 Read/Write

BLTC2 Double W. 00 FA5016 Read/Write

BLTR2 Double W. 00 FA5416 Read/Write

CNTL2 Word 00 FA5C16 Read/Write 000016

STAT2 Byte 00 FA5E16 Read Only 0016

ADCA3 Double W. 00 FA6016 Read/Write

ADRA3 Double W. 00 FA6416 Read/Write

ADCB3 Double W. 00 FA6816 Read/Write

ADRB3 Double W. 00 FA6C16 Read/Write

BLTC3 Double W. 00 FA7016 Read/Write

BLTR3 Double W. 00 FA7416 Read/Write

CNTL3 Word 00 FA7C16 Read/Write 000016

STAT3 Byte 00 FA7E16 Read Only 0016

A.1.4 General-Purpose I/O (GPIO) Ports

(Section 4.5.6 on page 119)

PADIR Byte 00 FE2016 Read/Write 0016

PADIN Byte 00 FE2216 Read Only

PADOUT Byte 00 FE2416 Read/Write

PAWPU Byte 00 FE2616 Read/Write 0016

PAALT Byte 00 FE2816 Read/Write 0016

PBDIR Byte 00 FE2A16 Read/Write 2016

PBDIN Byte 00 FE2C16 Read Only

PBDOUT Byte 00 FE2E16 Read/Write Bit 5 is 1; the

others are

undeﬁned

PBWPU Byte 00 FE3016 Read/Write 0016

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

www.national.com 410 Revision1.07

PC87591E/S/L

PBALT Byte 00 FE3216 Read/Write 4016

PCDIR Byte 00 FE3416 Read/Write 0016 PC0 is reset on

VCC Power-up

and

WATCHDOG

reset only.

PCDIN Byte 00 FE3616 Read Only

PCDOUT Byte 00 FE3816 Read/Write

PCWPU Byte 00 FE3A16 Read/Write 0016

PCALT Byte 00 FE3C16 Read/Write 0016

PDDIR Byte 00 FE3E16 Read/Write 0016

PDDIN Byte 00 FE4016 Read Only

PDDOUT Byte 00 FE4216 Read/Write

PDWPU Byte 00 FE4416 Read/Write 0016

PDALT Byte 00 FE4616 Read/Write 0016

PEDIN Byte 00 FE4816 Read Only

PEWPU Byte 00 FE4A16 Read/Write 0016

PEALT Byte 00 FE4C16 Read/Write 0016

KBSIN Byte 00 FE4E16 Read Only

KBSINPU Byte 00 FE5016 Read/Write

KBSOUT Word 00 FE5216 Read/Write FFFF16

PFDIR Byte 00 FE5416 Read/Write 0016

PFDIN Byte 00 FE5616 Read Only

PFDOUT Byte 00 FE5816 Read/Write

PFWPU Byte 00 FE5A16 Read/Write 0016

PFALT Byte 00 FE5C16 Read/Write 0016

PHDIR Byte 00 FB0016 Read/Write 0016

PHDIN Byte 00 FB0216 Read Only

PHDOUT Byte 00 FB0416 Read/Write

PIDIR Byte 00 FB0616 Read/Write 0016

PIDIN Byte 00 FB0816 Read Only

PIDOUT Byte 00 FB0A16 Read/Write

PJDIR Byte 00 FB0C16 Read/Write 0016

PJDIN Byte 00 FB0E16 Read Only

PJDOUT Byte 00 FB1016 Read/Write

PKDIR Byte 00 FB1216 Read/Write 0016

PKDIN Byte 00 FB1416 Read Only

PKDOUT Byte 00 FB1616 Read/Write

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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PLDIR Byte 00 FB1816 Read/Write 0016

PLDIN Byte 00 FB1A16 Read Only

PLDOUT Byte 00 FB1C16 Read/Write

PMDIR Byte 00 FB1E16 Read/Write 0016

PMDIN Byte 00 FB2016 Read Only

PMDOUT Byte 00 FB2216 Read/Write

A.1.5 PS/2 Ports

(Section 4.6.5 on page 128)

PSDAT Byte 00 FE8016 Read/Write

PSTAT Byte 00 FE8216 Read Only 0016

PSCON Byte 00 FE8416 Read/Write 0016

PSOSIG Byte 00 FE8616 Read/Write 4716

PSISIG Byte 00 FE8816 Read Only

PSIEN Byte 00 FE8A16 Read/Write 0016

A.1.6 Host Interface (KBC, PM1 and PM2Channels)

(Section 5.1.4 on page 282 and Section 5.2.3 on page 290)

HICTRL Byte 00 FEA016 Read/Write 0016

HIIRQC Byte 00 FEA216 Read/Write 0716

HIKMST Byte 00 FEA416 Read/Write 0016

HIKDO Byte 00 FEA616 Write Only

HIMDO Byte 00 FEA816 Write Only

HIKMDI Byte 00 FEAA16 Read Only

HIPM1ST Byte 00 FEAC16 Varies per bit 0016

HIPM1DO Byte 00 FEAE16 Write Only

HIPM1DI Byte 00 FEB016 Read Only

HIPM1DOC Byte 00 FEB216 Write Only

HIPM1DOM Byte 00 FEB416 Write Only

HIPM1DIC Byte 00 FEB616 Read Only

HIPM1CTL Byte 00 FEB816 Read/Write 4016

HIPM1IC Byte 00 FEBA16 Read/Write 4116

HIPM1IE Byte 00 FEBC16 Read/Write 0016

HIPM2ST Byte 00 FEBE16 Varies per bit 0016

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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HIPM2DO Byte 00 FEC016 Write Only

HIPM2DI Byte 00 FEC216 Read Only

HIPM2DOC Byte 00 FEC416 Write Only

HIPM2DOM Byte 00 FEC616 Write Only

HIPM2DIC Byte 00 FEC816 Read Only

HIPM2CTL Byte 00 FECA16 Read/Write C016

HIPM2IC Byte 00 FECC16 Read/Write 4116

HIPM2IE Byte 00 FECE16 Read/Write 0016

A.1.7 Multi-Function Timer (MTF16) 1

(Section 4.7.7 on page 142)

T1CNT1 Word 00 FD8016 Read/Write

T1CRA Word 00 FD8216 Read/Write

T1CRB Word 00 FD8416 Read/Write

T1CNT2 Word 00 FD8616 Read/Write

T1PRSC Byte 00 FD8816 Read/Write 0016

T1CKC Byte 00 FD8A16 Read/Write 0016

T1CTRL Byte 00 FD8C16 Read/Write 0016

T1ICTL Byte 00 FD8E16 Read/Write 0016

T1ICLR Byte 00 FD9016 Write Only

A.1.8 Multi-Function Timer (MFT16) 2

(Section 4.7.7 on page 142)

T2CNT1 Word 00 FDA016 Read/Write

T2CRA Word 00 FDA216 Read/Write

T2CRB Word 00 FDA416 Read/Write

T2CNT2 Word 00 FDA616 Read/Write

T2PRSC Byte 00 FDA816 Read/Write 0016

T2CKC Byte 00 FDAA16 Read/Write 0016

T2CTRL Byte 00 FDAC16 Read/Write 0016

T2ICTL Byte 00 FDAE16 Read/Write 0016

T2ICLR Byte 00 FDB016 Write Only

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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A.1.9 Timing and WATCHDOG (TWD)

(Section 4.10.3 on page 166)

TWCFG Byte 00 FEE016 Read/Write 0016

TWCP Byte 00 FEE216 Read/Write 0016

TWDT0 Word 00 FEE416 Read/Write FFFF16

T0CSR Byte 00 FEE616 Read/Write 0016

WDCNT Byte 00 FEE816 Write Only 0F16

WDSDM Byte 00 FEEA16 Write Only Write 5C16

A.1.10 Analog to Digital Converter (ADC)

(Section 4.11.6 on page 177)

ADCSTS Byte 00 FF2016 Varies per bit 0016 Bit 2 is reset on

VCC power up

reset only

ADCCNF Byte 00 FF2216 Read/Write 0016

ACLKCTL Byte 00 FF2416 Read/Write 3F16

ADLYCTL Byte 00 FF2616 Read/Write A716

TLOCOTL Byte 00 FF2816 Read/Write 7F16

ADCPINX Byte 00 FF2A16 Read/Write 0016

ADCPD Word 00 FF2C16 Read/Write

TCHANCTL Byte 00 FF3016 Varies per bit 1016

TCHANDAT Byte 00 FF3216 Read Only

VCHN1CTL Byte 00 FF3416 Varies per bit 1F16

VCHN1DAT Word 00 FF3616 Read Only

VCHN2CTL Byte 00 FF3816 Varies per bit 1F16

VCHN2DAT Word 00 FF3A16 Read Only

VCHN3CTL Byte 00 FF3C16 Varies per bit 1F16

VCHN3DAT Word 00 FF3E16 Read Only

A.1.11 Digital to Analog Converter (DAC)

(Section 4.12.5 on page 193)

DACCTRL Byte 00 FF4016 Read/Write 0016

DACDAT0 Byte 00 FF4216 Read/Write

DACDAT1 Byte 00 FF4416 Read/Write

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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PC87591E/S/L

DACDAT2 Byte 00 FF4616 Read/Write

DACDAT3 Byte 00 FF4816 Read/Write

A.1.12 ACCESS.bus Interface (ACB) 1

(Section 4.13.8 on page 202)

ACB1SDA Byte 00 FF6016 Read/Write

ACB1ST Byte 00 FF6216 Varies per bit 0016

ACB1CST Byte 00 FF6416 Varies per bit 0016

ACB1CTL1 Byte 00 FF6616 Read/Write 0016

ACB1ADDR Byte 00 FF6816 Read/Write

ACB1CTL2 Byte 00 FF6A16 Read/Write 0016

A.1.13 ACCESS.bus Interface (ACB) 2

(Section 4.13.8 on page 202)

ACB2SDA Byte 00 FFE016 Read/Write

ACB2ST Byte 00 FFE216 Varies per bit 0016

ACB2CST Byte 00 FFE416 Varies per bit 0016

ACB2CTL1 Byte 00 FFE616 Read/Write 0016

ACB2ADDR Byte 00 FFE816 Read/Write

ACB2CTL2 Byte 00 FFEA16 Read/Write 0016

A.1.14 Analog Comparators Monitor (ACM)

(Section 4.14.5 on page 212)

ACMCTS Byte 00 FD4016 Varies per bit 0016

ACMCNF Byte 00 FD4216 Read/Write 0016

ACMTIM Byte 00 FD4416 Read/Write 3716

THRDAT Byte 00 FD4616 Read/Write 0016

CMPRES Byte 00 FD4816 Read Only

VOLDAT0 Byte 00 FD5016 Read Only

VOLDAT1 Byte 00 FD5216 Read Only

VOLDAT2 Byte 00 FD5416 Read Only

VOLDAT3 Byte 00 FD5616 Read Only

VOLDAT4 Byte 00 FD5816 Read Only

VOLDAT5 Byte 00 FD5A16 Read Only

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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VOLDAT6 Byte 00 FD5C16 Read Only

VOLDAT7 Byte 00 FD5E16 Read Only

A.1.15 Power Management (PM)

(Section 4.17.4 on page 237)

PMCSR Byte 00 FF8016 Read/Write 0016

A.1.16 High Frequency Clock Generator (HFCG)

(Section 4.18.7 on page 243)

HFCGCTRL1 Byte 00 FFA016 Varies per bit 0C16

HFCGML Byte 00 FFA216 Read/Write CF16

HFCGMH Byte 00 FFA416 Read/Write 0316

HFCGN Byte 00 FFA616 Read/Write 0816

HFCGIL Byte 00 FFA816 Read/Write

HFCGIH Byte 00 FFAA16 Read/Write

HFCGP Byte 00 FFAC16 Read/Write 1716

HFCGCTRL2 Byte 00 FFAE16 Varies per bit 0016

A.1.17 Development System Support

(Section 4.20.8 on page 275)

DBGCFG Byte 00 FF1616 Read/Write 0016

DBGFRZEN Byte 00 FF1816 Read/Write FF16

A.1.18 Multi-Input Wake-Up (MIWU)

(Section 4.4.3 on page 109)

WKEDG1 Byte 00 FFC016 Read/Write 0016

WKEDG2 Byte 00 FFC216 Read/Write 0016

WKEDG3 Byte 00 FFC416 Read/Write 0016

WKEDG4 Byte 00 FFC616 Read/Write 0016

WKPND1 Byte 00 FFC816 Read/Write 0016

WKPCL1 Byte 00 FFCA16 Write Only

WKPND2 Byte 00 FFCC16 Read/Write 0016

WKPCL2 Byte 00 FFCE16 Write Only

WKPND3 Byte 00 FFD016 Read/Write 0016

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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WKPCL3 Byte 00 FFD216 Write Only

WKPND4 Byte 00 FFD416 Read/Write 0016

WKPCL4 Byte 00 FFD616 Write Only

WKEN1 Byte 00 FFD816 Read/Write 0016

WKEN2 Byte 00 FFDA16 Read/Write 0016

WKEN3 Byte 00 FFDC16 Read/Write 0016

WKEN4 Byte 00 FFDE16 Read/Write 0016

A.1.19 Interrupt Control Unit (ICU)

(Section 4.3.4 on page 101)

IVCT Byte 00 FE0016 Read Only 1016

NMISTAT Byte 00 FE0216 Read Only 0016

PFAIL Byte 00 FE0416 Read/Write 0016

ISTAT0 Word 00 FE0A16 Read Only 000016

ISTAT1 Word 00 FE0C16 Read Only 000016

IENAM0 Word 00 FE0E16 Read/Write 000016

IENAM1 Word 00 FE1016 Read/Write 000016

IECLR0 Word 00 FE1216 Write Only

IECLR1 Word 00 FE1416 Write Only

A.1.20 Debugger Interface

(Section 4.19.9 on page 267)

DBGRXD0 Word 00 FDC016 Read Only

DBGRXD2 Word 00 FDC216 Read Only

DBGRXD4 Word 00 FDC416 Read Only

DBGRXD6 Word 00 FDC616 Read Only

DBGRXD8 Word 00 FDC816 Read Only

DBGRXD10 Word 00 FDCA16 Read Only

DBGRXD12 Word 00 FDCC16 Read Only

DBGRXD14 Word 00 FDCE16 Read Only

DBGTXD0 Word 00 FDD016 Read/Write

DBGTXD2 Word 00 FDD216 Read/Write

DBGTXD4 Word 00 FDD416 Read/Write

DBGTXD6 Word 00 FDD616 Read/Write

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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DBGTXD8 Word 00 FDD816 Read/Write

DBGTXD10 Word 00 FDDA16 Read/Write

DBGTXD12 Word 00 FDDC16 Read/Write

DBGTXD14 Word 00 FDDE16 Read/Write

DBGRXST Byte 00 FDE016 Varies per bit

DBGTXST Byte 00 FDE216 Read/Write 0016

DBGTXLOC Byte 00 FDE416 Read/Write 0F16

DBGTINT Byte 00 FDE616 Write Only

DBGABORT Word 00 FDE816 Write Only

DBGISESRCA Word 00 FDEA16 Read/Write 000016

A.1.21 Pulse Width Modulator (PWM)

(Section 4.8.5 on page 148)

PRSC Byte 00 FD0016 Read/Write 0016

CTR Byte 00 FD0216 Read/Write FF16

PWMPOL Byte 00 FD0416 Read/Write 0016

PWMCNT Byte 00 FD0616 Read/Write 0016

DCR0 Byte 00 FD0816 Read/Write 0016

DCR1 Byte 00 FD0A16 Read/Write 0016

DCR2 Byte 00 FD0C16 Read/Write 0016

DCR3 Byte 00 FD0E16 Read/Write 0016

DCR4 Byte 00 FD1016 Read/Write 0016

DCR5 Byte 00 FD1216 Read/Write 0016

DCR6 Byte 00 FD1416 Read/Write 0016

DCR7 Byte 00 FD1616 Read/Write 0016

A.1.22 Universal Synchronous/Asynchronous Receiver Transmitter (USART)

(Section 4.9.4 on page 158)

UTBUF Byte 00 FD2016 Read/Write

URBUF Byte 00 FD2216 Read Only

UICTRL Byte 00 FD2416 Varies per bit 0116

USTAT Byte 00 FD2616 Read Only 0016

UFRS Byte 00 FD2816 Read/Write 0016

UMDSL Byte 00 FD2A16 Read/Write 0016

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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UBAUD Byte 00 FD2C16 Read/Write 0016

UPSR Byte 00 FD2E16 Read/Write 0016

A.1.23 Flash Interface

(Section 4.16.7 on page 228)

IBAI Word 00 F88016 Read/Write

IBD Word 00 F88216 Read/Write

FCWP0 Word 00 F89016 Read/Write 000016

FLCR Word F8C016 Read/Write 000016

FLSR Byte F8C216 Varies per bit 0016

FLPSLR Byte F8C416 Read/Write 0016

FLSTART Byte F8C616 Read/Write 1416

FLTRAN Byte F8CA16 Read/Write 2816

FLPROG Byte F8D016 Read/Write 0A16

FLPERASE Byte F8D216 Read/Write 0916

FLSERASE Byte F8D416 Read/Write 0916

FLEND Byte F8D816 Read/Write 1416

FLSEND Byte F8DC16 Read/Write 3216

FLRCV Byte F8DE16 Read/Write 0416

A.1.24 Shared Memory Core

(Section 5.3.9 on page 307)

SMCCST Byte 00 F90016 Read/Write 0016

SMCTA Byte 00 F90216 Read/Write and

Read Only See description

SMHSEM Byte 00 F90416 Varies per bit 0016

SMCORP0 Word 00 F91016 Varies per bit See description

SMCORP1 Word 00 F91216 Varies per bit See description

SMCORP2 Word 00 F91416 Varies per bit See description

SMCOWP0 Word 00 F92016 Read/Write FFFF16

SMCOWP1 Word 00 F92216 Read/Write FFFF16

SMCOWP2 Word 00 F92416 Read/Write FFFF16

RNGCS Byte 00 F93016 Varies per bit 0016

RNGD Byte 00 F93216 Read Only

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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A.1.25 Core Access to SuperI/O

IHIOA Word 00 FCE016 Read/Write 0016

IHD Byte 00 FCE216 Read/Write 0016

LKSIOHA Word 00 FCE416 Read/Write 000216/000016

SIOLV Word 00 FCE616 R/W1C 000016

CRSMAE Word 00 FCE816 Read/Write 000016

SIBCTRL Byte 00 FCEA16 Varies per bit 0016

A.1.26 Mobile System Wake-Up Control (MSWC)

(Section 5.5.6 on page 328)

MSWCTL1 Byte 00 FCC016 Varies per bit 0016 Vcc power-up

only

MSWCTL2 Byte 00 FCC216 Varies per bit 0016

MSWCTL3 Byte 00 FCC416 Varies per bit 0116 VPP power-up

only

HCFGBAL Byte 00 FCC816 Read/Write 0016

HCFGBAH Byte 00 FCCA16 Read/Write 0016

MSIEN2 Byte 00 FCCC16 Read/Write 0016

MSHES0 Byte 00 FCCE16 R/W1C 0016

MSHEIE0 Byte 00 FCD016 Read/Write 0016

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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A.2 HOST DOMAIN REGISTER LIST

A.2.1 Conﬁguration Registers

Access to all host configuration registers is via an index/data scheme that uses the host configuration index/data pair.

A.2.2 Host Runtime Registers

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Common SuperI/O Conﬁguration

(Section 6.1.8 on page 343)

SID Byte Index 2016 Read Only EC16

SIOCF1 Byte Index 2116 Varies per bit 1116

SIOCF5 Byte Index 2516 Read/Write 0016

SIOCF6 Byte Index 2616 Read/Write 0016

SRID Byte Index 2716 Read Only

SIOCF8 Byte Index 2816 Read/Write 0016

SIOCF9 Byte Index 2916 Read/Write 0116

SIOCFD Byte Index 2D16 Read/Write 0016

Shared Memory

(Section 6.1.11 on page 349)

SharedMemory

Conﬁguration Byte Index F416 Read/Write 0016 or 0916

depending on

SHBM strap

SharedMemory

Base Address

High Byte Byte Index F516 Read/Write 0016

SharedMemory

Base Address

Low Byte Byte Index F616 Read/Write 0016

SharedMemory

Size Conﬁg Byte Index F716 Read/Write 0016

RTC Conﬁguration

When LDN is set to 1016. (Section 6.1.12 on page 353)

RLR Byte Device

Speciﬁc Read/Write 0016 Cleared by H/W

reset only

DOMAO Byte Index F016 Read/Write 0016

MONAO Byte Index F116 Read/Write 0016

CENO Byte Index F316 Read/Write 0016

Software for Hardware Interface (Continued)

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Module Register Name Size Register

Address Access Type Value After

Reset Comments

Shared Memory Host

The base address is defined by LDN 0F16 (Section 5.3.8 on page 303).

SMIMA0 Byte Offset 0016 Read/Write

SMIMA1 Byte Offset 0116 Read/Write

SMIMA2 Byte Offset 0216 Read/Write

SMIMA3 Byte Offset 0316 Read/Write

SMIMD Byte Offset 0416 Read/Write

SMHC Byte Offset 0516 Read/Write 0016

SMHST Byte Offset 0616 Varies per bit 0016

SMHAP1 Byte Offset 0716 Varies per bit 0216

SMHAP2 Byte Offset 0816 Varies per bit 0216

SMHSEM Byte Offset 0C16 Varies per bit 0016

MSWC Host Registers

The base address is defined by LDN 0416 (Section 5.5.5 on page 323).

WK_STS0 Byte Offset 0016 R/W1C 0016

WK_EN0 Byte Offset 0216 Read/Write 0016

WK_CFG Byte Offset 0416 Read/Write 0016

WK_SIGV Byte Offset 0616 Read Only

WK_STATE Byte Offset 0716 Read/Write

WK_SMIEN0 Byte Bank 2

Offset 1316 Read/Write 0016

WK_IRQEN0 Byte Bank 2

Offset 1516 Read/Write 0016

Host Interface (HI)

The base address is defined by LDN 0616 (“Host Addresses” on page 277).

DBBOUT Byte

Deﬁned in

LDN 0616

index 6016,

6116

STATUS Byte

Deﬁned in

LDN 0616

index 6216,

6316

R0016

DBBIN Byte

Deﬁned in

LDN 0616

index 6016,

6116

Software for Hardware Interface (Continued)

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COMAND Byte

Deﬁned in

LDN 0616

index 6216,

6316

Power Management Channel 1

The base address is defined by LDN 1116 (“Host Addresses” on page 277).

DBBOUT Byte

Deﬁned in

LDN 1116

index 6016,

6116

STATUS Byte

Deﬁned in

LDN 1116

index 6216,

6316

R0016

DBBIN Byte

Deﬁned in

LDN 1116

index 6016,

6116

COMAND Byte

Deﬁned in

LDN 1116h

index 6216,

6316

Power Management Channel 2

The base address is defined by LDN 1216 (“Host Addresses” on page 277).

DBBOUT Byte

Deﬁned in

LDN 1216

index 6016,

6116

STATUS Byte

Deﬁned in

LDN 1216

index 6216,

6316

R0016

DBBIN Byte

Deﬁned in

LDN 1216

index 6016,

6116

COMAND Byte

Deﬁned in

LDN 1216

index 6216,

6316

RTC

Access is via a index/data scheme that uses an index/data pair pointed to by LDN 1016 (Section 6.2.15 on page 363).

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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SEC Byte Index 0016 Read/Write 0016

SECA Byte Index 0116 Read/Write 0016

MIN Byte Index 0216 Read/Write 0016

MINA Byte Index 0316 Read Only 0016

HOR Byte Index 0416 Read/Write 0016

HORA Byte Index 0516 Read/Write 0016

DOW Byte Index 0616 Read/Write 0016

DOM Byte Index 0716 Read/Write 0016

MON Byte Index 0816 Read/Write 0016

YER Byte Index FF16 Read/Write 0016

CRA Byte Index 0A16 Read/Write 2016

CRB Byte Index 0B16 Read/Write 0016

CRC Byte Index 0C16 Read Only 0016

CRD Byte Index 0D16 Read Only 0016

DOMA Byte Prog. Index Read/Write C016

MONA Byte Prog. Index Read/Write C016

CEN Byte Prog. Index Read/Write 0016

Module Register Name Size Register

Address Access Type Value After

Reset Comments

Software for Hardware Interface (Continued)

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A.3 CORE DOMAIN REGISTER LAYOUT

A.3.1 Module Conﬁguration

(Section 2.3 on page 53 and Section 2.4.2 on page 58)

A.3.2 Bus Interface Unit (BIU)

(Section 4.1.10 on page 83)

A.3.3 DMA Controller

(Section 4.2.8 on page 92)

A.3.4 General-Purpose I/O (GPIO) Port

(Section 4.5.6 on page 119)

76543210

MCFG/MCFGSH GTMON Reserved CLKOM EXMEM16 ENEMEM ENEIO

EICFG Reserved EXWINT46 EXWINT45

IOEE1 Reserved EEPA4 EEPA3 EEPA2 EEPA1 EEPA0

IOEE2 Reserved EEPC0 EEPD3 EEPB2 EEPB1 EEPB0

STRPST (p. 53) Reserved Reserved Reserved Reserved Reserved BADDR1 BADDR0 SHBM

15 12 11 10 9 8 7 6 5 4 3 2 1 0

BCFG N/A Reserved ISTL OBR EWR

IOCFG Reserved IPS

TRes BW Reserved HOLD WAIT

SZCFGn Reserved FRE IPRE IPS

TRes BW WBR BRE HOLD WAIT

09876543210

ADCAn Device A Address Counter

ADRAn Device A Address

ADCBn Device B Address Counter

ADRBn Device B Address

BLTCn Reserved Block Length Counter

BLTRn Reserved Block Length

CNTLn N/A R

STATn N/A Reserved V

7 6 543210

PADIR PA Port Direction

PBDIR PB Port Direction

PCDIR PC Port Direction

PDDIR PD Port Direction

PFDIR PF Port Direction

PGDIR PG Port Direction

PIDIR PI Port Direction

PJDIR PJ Port Direction

PKDIR PK Port Direction

PLDIR Reserved PL Port Direction

PMDIR PM Port Direction

PADIN PA Port Input Data

PBDIN PB Port Input Data

Software for Hardware Interface (Continued)

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A.3.5 PS/2 Interface

(Section 4.6.5 on page 128)

A.3.6 Core Interface

(Section 5.1.4 on page 282 and Section 5.2.3 on page 290)

PCDIN PC Port Input Data

PDDIN PD Port Input Data

PEDIN PE Port Input Data

PFDIN PF Port Input Data

PHDIN PH Port Input Data

PIDIN PI Port Input Data

PJDIN PJ Port Input Data

PKDIN PK Port Input Data

PLDIN Reserved PL Port Input Data

PMDIN PM Port Input Data

PADOUT PA Port Output Data

PBDOUT PB Port Output Data

PCDOUT PC Port Output Data

PDDOUT PD Port Output Data

PFDOUT PF Port Output Data

PHDOUT PH Port Output Data

PIDOUT PI Port Output Data

PJDOUT PJ Port Output Data

PKDOUT PK Port Output Data

PLDOUT Reserved PL Port Output Data

PMDOUT PM Port Output Data

PAWPU PA Port Weak Pull-up Enable

PBWPU PB Port Weak Pull-up Enable

PCWPU PC Port Weak Pull-up Enable

PDWPU PD Port Weak Pull-up Enable

PEWPU PE Port Weak Pull-up Enable Reserved PE Port

Weak Pull-

up Enable Reserved

PFWPU PF Port Weak Pull-up Enable

PAALT PA Pins Alternate Function Enable

PBALT PB Pins Alternate Function Enable

PCALT PC Pins Alternate Function Enable

PDALT PD Pins Alternate Function Enable

PEALT PE Pins Alternate Function Enable

PFALT PF Pins Alternate Function Enable

76 5 4 3 2 10

PSDAT Data

PSTAT Reserved RFERR ACH PERR EOT SOT

PSCON WPUEN IDB HDRV XMT EN

PSOSIG CLK4 WDAT4 CLK3 CLK2 CLK1 WDAT3 WDAT2 WDAT1

PSISIG RCLK4 RDAT4 RCLK3 RCLK2 RCLK1 RDAT3 RDAT2 RDAT1

PSIEN Reserved DSMIE EOTIE SOTIE

76543210

HICTRL Reserved PMICIE PMOCIE PMHIE IBFCIE OBECIE OBFMIE OBFKIE

HIIRQC Reserved IRQNPOL IRQM IRQ11B IRQ12BO

BFMIE IRQ1B

HIKMST ST3 ST2 ST1 ST0 A2 F0 IBF OBF

HIKDO Keyboard DBBOUT Data

HIMDO Mouse DBBOUT Data

HIKMDI Keyboard/Mouse DBBIN Data

7 6 543210

Software for Hardware Interface (Continued)

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A.3.7 Multi-Function Timer (MFT16)

(Section 4.7.7 on page 142)

A.3.8 Timing and WATCHDOG (TWD)

(Section 4.10.3 on page 166)

A.3.9 Analog to Digital Converter (ADC)

(Section 4.11.6 on page 177)

HIPMnST ST3 ST2 ST1 ST0 A2 F0 IBF OBF

HIPMnDO PM Channel DBBOUT Data

HIPMnDOC PM Channel DBBOUT Data

HIPMnDOM PM Channel DBBOUT Data

HIPMnDI PM Channel DBBIN Data

HIPMnDIC PM Channel DBBIN Data

HIPMnCTRL EME SCIPOL PLMS Reserved OBEIE IBFIE

HIPMnIC SCIIS SMIPOL PLMM SCIB SMIB IRQB

HIPMnIE Reserved HSMIE HSCIE HIRQE SMIE SCIE IRQE

15876543210

TnPRSC N/A Reserved CLKPS

TnCKC N/A Reserved C2CSEL C1CSEL

TnCTRL N/A Reserved TAOUT TBEN TAEN TBEDG TAEDG MDSEL

TnICTL N/A TDIEN TCIEN TBIEN TAIEN TDPND TCPND TBPND TAPND

TnICLR N/A Reserved TDCLR TCCLR TBCLR TACLR

15 8 7 6 5 4 3 2 1 0

TWCFG N/A Reserved WDSDME WDCT0I LWDCNT LTWDT0 LTWCP LTWCFG

TWCP N/A Reserved MDIV

TWDT0 Preset

T0CSR N/A Reserved WDLTD Reserved TC RST

WDCNT N/A PRESET

WDSDM N/A RSDATA

15109876543210

ADCSTS N/A Reserved OPSH-

TYPE OP-

SHEV OTSEV OVFEV EOCEV

ADCCNF N/A Reserved INTO-

SEN INTO-

TEN INTE-

CEN REM-

DEN ADCEN

ACLKCTL N/A Reserved SCLKDIV

ADLYCTL N/A TMPDLY Res VOLDLY

TLOCOTL N/A OTSLIM

ADCPINX N/A Index

ADCPD Parameter Data

TCHANCTL N/A DATVAL RDMEA

SEN INTD-

VEN SELIN

TCHANDAT N/A TCHDAT

VCHN1CTL N/A DATVAL CSCALE INTD-

VEN SELIN

VCHN1DAT Reserved VCHDAT

VCHN2CTL N/A DATVAL CSCALE INTD-

VEN SELIN

VCHN2DAT Reserved VCHDAT

VCHN3CTL N/A DATVAL CSCALE INTD-

VEN SELIN

VCHN3DAT Reserved VCHDAT

76543210

Software for Hardware Interface (Continued)

Revision 1.07 427 www.national.com

PC87591E/S/L

A.3.10 Digital to Analog (DAC)

(Section 4.12.5 on page 193)

A.3.11 ACCESS.bus Interface (ACB)

(Section 4.13.8 on page 202)

A.3.12 Analog Comparators Monitor (ACM)

(Section 4.14.5 on page 212)

A.3.13 Power Management (PM)

(Section 4.17.4 on page 237)

A.3.14 High-Frequency Clock Generator (HFCG)

(Section 4.18.7 on page 243)

A.3.15 Development System Support

(Section 4.20.8 on page 275)

A.3.16 Multi-Input Wake-Up (MIWU)

(Section 4.4.3 on page 109)

76543210

DACCTRL Reserved ENIDLE DACEN3 DACEN2 DACEN1 DACEN0

DACDATi DAC DATAi

765432 1 0

ACBnSDA DATA

ACBnST SLVSTP SDAST BER NEGACK STASTR NMATCH MASTER XMIT

ACBnCST ARP-

MATCH MATCHAF TGSCL TSDA GMATCH MATCH BB BUSY

ACBnCTL1 STASTRE NMINTE GCMEN ACK Reserved INTEN STOP START

ACBnADDR SAEN ADDR

ACBnCTL2 SCLFRQ6 SCLFRQ5 SCLFRQ4 SCLFRQ3 SCLFRQ2 SCLFRQ1 SCLFRQ0 ENABLE

765432 1 0

ACMCTS Reserved OVUNTHEV EOCEV EOMEV START

ACMCNF Reserved OVUNSEL INTOUEN INTEMEN Reserved ACMMOD

ACMTIM Reserved T0DIV Reserved SMPDLY

THRDAT Reserved THRSHD5 THRSHD4 THRSHD3 THRSHD2 THRSHD1 THRSHD0

CMPRES CMPIN7 CMPIN6 CMPIN5 CMPIN4 CMPIN3 CMPIN2 CMPIN1 CMPIN0

VOLDAT0-7 Reserved Voltage Level Data 5-0

76 5 4 3210

PMCSR OLFC OHFC WBPSM Reserved IDLE DHF Reserved

7 65432 1 0

HFCGCTRL1 Reserved FAST96 LOAD96 IVLID OHFC PENABLE FAST LOAD

HFCGML HFCGM7-0

HFCGMH HFCGM

HFCGN Reserved HFCGN4-0

HFCGIL HFCGI7-0

HFCGIH Reserved HFCGI13-8

HFCGP Reserved HFCGP4-0

HFCGCTRL2 Reserved 96MON MONERR SCESTP SCESTR SENABLE

76543210

DBGCFG Reserved BRKLE FREEZE ON

DBGFRZEN Reserved HIFEN USARTFEN ACB2FEN ACB1FEN MFT2FEN MFT1FEN

765 4 3 2 10

Software for Hardware Interface (Continued)

www.national.com 428 Revision1.07

PC87591E/S/L

A.3.17 Interrupt Control Unit (ICU)

(Section 4.3.4 on page 101)

A.3.18 Debugger Interface

(Section 4.19.9 on page 267)

WKEDG1 WKED17 WKED16 WKED15 WKED14 WKED03 WKED12 WKED11 WKED10

WKEDG2 WKED27 WKED26 WKED25 WKED24 WKED23 WKED22 WKED21 WKED20

WKEDG3 WKED37 WKED36 WKED35 WKED34 WKED33 WKED32 WKED31 WKED30

WKEDG4 WKED47 WKED46 WKED45 WKED44 WKED43 WKED42 WKED41 WKED40

WKPND1 WKPD17 WKPD16 WKPD15 WKPD14 WKPD03 WKPD12 WKPD11 WKPD10

WKCL1 WKCL17 WKCL16 WKCL15 WKCL14 WKCL03 WKCL12 WKCL11 WKCL10

WKPND2 WKPD27 WKPD26 WKPD25 WKPD24 WKPD23 WKPD22 WKPD21 WKPD20

WKCL2 WKCL27 WKCL26 WKCL25 WKCL24 WKCL23 WKCL22 WKCL21 WKCL20

WKPND3 WKPD37 WKPD36 WKPD35 WKPD34 WKPD33 WKPD32 WKPD31 WKPD30

WKCL3 WKCL37 WKCL36 WKCL35 WKCL34 WKCL33 WKCL32 WKCL31 WKCL30

WKPND4 WKPD47 WKPD46 WKPD45 WKPD44 WKPD43 WKPD42 WKPD41 WKPD40

WKCL4 WKCL47 WKCL46 WKCL45 WKCL44 WKCL43 WKCL42 WKCL41 WKCL40

WKEN1 WKEN17 WKEN16 WKEN15 WKEN14 WKEN13 WKEN12 WKEN11 WKEN10

WKEN2 WKEN27 WKEN26 WKEN25 WKEN24 WKEN23 WKEN22 WKEN21 WKEN20

WKEN3 WKEN37 WKEN36 WKEN35 WKEN34 WKEN33 WKEN32 WKEN31 WKEN30

WKEN4 WKEN47 WKEN46 WKEN45 WKEN44 WKEN43 WKEN42 WKEN41 WKEN40

1512118765432 1 0

IVCT N/A 0 0 INTVECT

NMISTAT N/A Reserved EXT

PFAIL N/A Reserved ENLCK PIN EN

ISTAT0 Interrupt Status Register (15-0)

ISTAT1 Interrupt Status Register (31-16)

IENAM0 Interrupt Enable (15-0)

IENAM1 Interrupt Enable (31-16)

158765432 1 0

DBGRXD0 RX_Data0

DBGRXD2 RX_Data2

DBGRXD4 RX_Data4

DBGRXD6 RX_Data6

DBGRXD8 RX_Data8

DBGRXD10 RX_Data10

DBGRXD12 RX_Data12

DBGRXD14 RX_Data14

DBGTXD0 TX_Data0

DBGTXD2 TX_Data2

DBGTXD4 TX_Data4

DBGTXD6 TX_Data6

DBGTXD8 TX_Data8

DBGTXD10 TX_Data10

DBGTXD12 TX_Data12

DBGTXD14 TX_Data14

DBGRXST N/A MSG_LEN PID RX_BUSY

DBGTXST N/A Reserved MSG_LEN

DBGTXLOC N/A Reserved PID

DBGTINT N/A Reserved ASSERT

DBGABORT Reserved P_0

DBGISESRCA Reserved ABORT_0 RX_0

Software for Hardware Interface (Continued)

Revision 1.07 429 www.national.com

PC87591E/S/L

A.3.19 Pulse with Modulator (PWM)

(Section 4.8.5 on page 148)

A.3.20 Universal Synchronous/Asynchronous Receiver Transmitter (USART)

(Section 4.9.4 on page 158)

A.3.21 Flash Interface

(Section 4.16.7 on page 228)

A.3.22 Shared Memory Core

(Section 5.3.9 on page 307)

765 4 3 2 10

PRSC PRSC(7-0)

CTR CTR(7-0)

PWMPOL INVP(7-0)

PWMCNT Reserved PWR

DCRi DCRi(7-0)

765 4 3 2 10

UTBUF UTBUF

URBUF URBUF

UICTRL EEI ERI ETI Reserved Reserved Reserved RBF TBE

USTAT Reserved XMIP RB9 BKD ERR DOE FE PE

UFRS Reserved PEN PSEL XB9 STP CHAR

UMDSL Reserved Reserved ERD ETD CKS BRK UnATN MOD

UBAUD UDIV(7-0)

UPSR UPSC UDIV(10-8)

15 9 8 7 6 5 4 3 2 1 0

IBAI Reserved Indirect Memory Address (7-0)

IBD Information Block Data

FCWP0 FC0WP(15-0)

FCWP1 FC1WP(15-0)

FCWP2 FC2WP(15-0)

FLCR Res DIS-

VRF SMER PMER PE IENPROG Reserved LOWP-

WRS LOWP-

WRF

FLSR N/A Reserved DERR FMLFULL FMBUSY PERR EERR

FLPSLR N/A Reserved FTDIV(3-0)

FLSTART N/A FTSTART(7-0)

FLTRAN N/A FTTRAN(7-0)

FLPROG N/A FTPROG(7-0)

FLPERASE N/A FTPER(7-0)

FLSERASEi N/A FTSER(7-0)

FLEND N/A FTEND(7-0)

FLSEND N/A FTSEND(7-0)

FLRCV N/A FTRCV(7-0)

15 8 7 6 5 4 3 2 1 0

SMCCST N/A HSEMIE HSEMW HLOCK HERES HERRIEN HWERR HRERR

SMCTA N/A Reserved MBSD

SMHSEM N/A CSEM3 CSEM2 CSEM1 CSEM0 HSEM3 HSEM2 HSEM1 HSEM0

SMCOHRP0 ORPLA(15-0)

SMCOHRP1 ORP(15-2) Reserved

SMCOHRP2 ORP(31-16)

SMCOHWP0 OWPLA(15-0)

SMCOHWP1 OWP(15-2) Reserved

SMCOHWP2 OWP(31-16)

Software for Hardware Interface (Continued)

www.national.com 430 Revision1.07

PC87591E/S/L

A.3.23 Core Access to SuperI/O

(Section 5.4.1 on page 314)

A.3.24 MSWC

(Section 5.5.6 on page 328)

RNGCS N/A Reserved CLKP DVALID RNGE

RNGD N/A RNGD(0-7)

15 8 7 6 5 4 3 2 1 0

IHIOA Reserved Indirect Host I/O Offset

IHD N/A Indirect Host Data

LKSIOHA Reserved LKRTCHA LKCFG

SIOLV Reserved RTCLV CFGLV

CRSMAE Reserved RTCAE CFGAE

SIBCTRL N/A Reserved RTCMR CSWR CSRD CSAE

765 4 3 2 10

MSWCTL1 Reserved HSECM VHCFGLK VHCFGA LPCRSTA HPWRON HRSTOB

MSWCTL2 CFGPSO CFGPBM ACPIS5 ACPIS4 ACPIS3 ACPIS2 ACPIS1 ACPIS0

MSWCTL3 Reserved RTCAL LPFTO HRAPU

HCFGBAL Host Conﬁguration Registers Base Address Low

HCFGBAH Host Conﬁguration Registers Base Address High

MSIEN2 EICFGPSO EICFG-

PBM EIACPIS5 EIACPIS4 EIACPIS3 EIACPIS2 EIACPIS1 EIRTCAL

MSHES0 Module

IRQ Event

Status

Software

Event Sta-

tus Reserved RINGEvent

Status Reserved RI2 Event

Status RI1 Event

Status

MSHEIE0 Module

IRQ Event

Enable

Software

Event

Enable Reserved RINGEvent

Enable Reserved RI2 Event

Enable RI1 Event

Enable

15 8 7 6 5 4 3 2 1 0

Software for Hardware Interface (Continued)

Revision 1.07 431 www.national.com

PC87591E/S/L

A.4 HOST DOMAIN REGISTER LAYOUT

Host Conﬁguration Registers

A.4.1 SuperI/O Conﬁguration

(Section 6.1.8 on page 343)

A.4.2 Shared Memory Conﬁguration

(Section 6.1.11 on page 349)

A.4.3 RTC Conﬁguration

(Section 6.1.12 on page 353)

Host Runtime Registers

A.4.4 Shared Memory Host

(Section 5.3.8 on page 303)

7 6543210

SID Family ID

SIOCF1 Reserved Number of DMA Wait

States Number of I/O Wait

States Software

Reset SuperI/O

Devices

Enable

SIOCF5 Reserved SMItoIRQ2

Enable Reserved

SIOCF6 SCIOF6 Soft-

ware Lock General-Purpose

Scratch RTC

Disabled Reserved

SRID Chip Revision ID

SIOCF8 Reserved LPC Bus Master Num. Reserved

SIOCF9 Reserved Module

Enable

Status

Valid Multi-

plier Clock

Status Clock

Enable SuperI/O Clock Domain

Source

SIOCFD Reserved Power

Supply Off Power But-

ton Mode

7 6543210

Shared Memory

Conﬁguration BIOS FWH ID BIOS FWH

Enable

User-De-

ﬁned Mem-

ory Space

Enable

BIOS Ex-

tended

Space En-

able

BIOS LPC

Enable

Shared Memory

Base Address

High Byte User-Deﬁned Memory Zone Address High

Shared Memory

Base Address

Low Byte User-Deﬁned Memory Zone Address Low

Shared Memory

Size Conﬁguration Reserved User-Deﬁned Memory Zone Size

7 6543210

RLR Block

Standard

RAM Block

RAM Write Block

Extended

RAM Write

Block

Extended

RAM Read

Block

Extended

RAM Reserved

DOMAO Reserved Date of Month Alarm Register Offset Value

MONAO Reserved Month Alarm Register Offset Value

CENO Reserved Century Register Offset Value

7 6543210

SMIMA0 Indirect Memory Address (7-0)

SMIMA1 Indirect Memory Address (15-8)

SMIMA2 Indirect Memory Address (23-16)

Software for Hardware Interface (Continued)

www.national.com 432 Revision1.07

PC87591E/S/L

A.4.5 MSWC Host

(Section 5.5.5 on page 323)

A.4.6 Host Interface (HI) Registers

(“Host Addresses” on page 277)

A.4.7 RTC Registers

(Section 6.2.15 on page 363)

SMIMA3 Indirect Memory Address (31-24)

SMIMD Indirect Memory Data (7-0)

SMHC Reserved PMER Reserved

SMHST Reserved HDERR FMLFULL HBUSY HPERR HEERR

SMHAP1,2 Host Access Protection Index Index Write Host Lock

Protection Host Write

Protection Host Read

Protection

SMHSEM CSEM3 CSEM2 CSEM1 CSEM0 HSEM3 HSEM2 HSEM1 HSEM0

7 6543210

WK_STS0 Module IRQ

Event Status Software

Event Sta-

tus Reserved RING

Event

Status Reserved RI2 Event

Status RI1 Event

Status

WK_EN0 Module IRQ

Event Enable Software

Event

Enable Reserved RING

Event

Enable Reserved RI2 Event

Enable RI1 Event

Enable

WK_CFG Reserved Conﬁguration Bank

Select

WK_SIGV Reserved PWUREQ

Wakeup

or IRQ

PWUREQ

Output

Value PM2 SMI

Output PM1 SMI

Output SMI Wake-

up Output SMIOutput

Value

WK_STATE Reserved S5 S4 S3 S2 S1 Reserved

WK_SMIEN0 Reserved Software

Event to

SMI

Enable Reserved Ring Event

to SMI

Enable Reserved RI2 Event

to SMI

Enable

RI1 Event

to SMI

Enable

WK_IRQENO Reserved Software

Event to

IRQ

Enable Reserved Ring Event

to IRQ

Enable Reserved RI2 Event

to IRQ

Enable

RI1 Event

to IRQ

Enable

76543210

DBBOUT Keyboard/Mouse DBBOUT Data

STATUS ST3 ST2 ST1 ST0 A2 F0 IBF OBF

DBBIN Keyboard/Mouse DBBIN Data

COMAND Keyboard/Mouse DBBIN Data

7 6543210

SEC Seconds Data

SECA Seconds Alarm Data

MIN Minutes Data

MINA Minutes Alarm Data

HOR Hours Data

HORA Hours Alarm Data

DOW Day of Week Data

DOM Date of Month Data

MON Month Data

YER Year Data

CRA Update in

Progress Divider Chain Control 2-0 Periodic Interrupt Rate Select 3-0

Software for Hardware Interface (Continued)

Revision 1.07 433 www.national.com

PC87591E/S/L

CRB Set Mode Periodic

Interrupt

Enable

Alarm

Interrupt

Enable

Update

Ended

Interrupt

Enable Reserved Data Mode Hour Mode Daylight

Savings

CRC IRQ Flag Periodic

Interrupt

Flag

Alarm

Interrupt

Flag

Update

Ended

Interrupt

Flag Reserved

CRD Valid RAM

and Time Reserved

DOMA Date of Month Alarm Data

MONA Month Alarm Data

CEN Century Data

www.national.com 434 Revision1.07

PC87591E/S/L

B. Software for Hardware Interface

B.1 FACTORY PARAMETERS

The following table is stored in the factory parameters section of the flash.

RevisionCode Interpretation

●00xx16 - Pre-production versions; contact NSC for usage guidelines.

●01xx16 - Production version xx of PC87591x devices (xx is a version number starting with 0x00).

●02xx16 - Production version xx of PC87591x devices with special handling noted in user information.

●FFxx16 - A non-tested device; contact National Semiconductor for usage guidelines.

●Other - Reserved for future use.

The ADC should be initialized after reset with the factory parameters setting that are stored in flash memory. The code below

is an example of how the data may be loaded into the ADC.

#define IBAI (*((volatile unsigned short *)0xF880))

#define IBD (*((volatile unsigned short *)0xF882))

#define ADCPINX (*((volatile unsigned char*)0xFF2A))

#define ADCPD (*((volatile unsigned int *)0xFF2C))

void CalibrateADC()

{unsigned int i, count;

IBAI = 0x0000; // Set address to RevisionCode

if ( (IBD & 0xff00) == 0x0100) // Check that RevisionCode is 0x01yy;

// refer to user information on

// other cases.

{ // Factory Parameters are programed with the correct version

IBAI= 0x0002; // Set address to ‘count’

count = IBD; // Read the number of elements to copy

for (i=1; i<= count ; i++)

{ADCPINX = (unsigned char)i; // Set pointer in ADC register

IBAI = 2*i+2; // Set pointer in Flash

ADCPD = IBD; // Copy from flash to ADC register

}

ADCPINX = 0x00; // change the index back to the default register.

ADCPD = 0x0001; // Lock the ADC calibration registers.}

}

Information Block Address Data [Word]

000016 unsigned int RevisionCode

000216 unsigned int count

007C16 Copy of SRID register indication for the

device revision number.

For PC87591E: FF0n16

For PC87591S: FF2n16

Software for Hardware Interface (Continued)

Revision 1.07 435 www.national.com

PC87591E/S/L

B.2 PROTECTION INFORMATION

The flash protection word is used to protect the contents of the on-chip flash from being altered. It also prevents the system

from executing from an erased flash and sets various system defaults. The following are examples of common settings for the

protection word. The protection word should be written into the flash as the last operation after updating the flash via the JTAG.

The protection word may be written by a write operation, using the programing tool to address 00FE16 in the information block

(block 2). Note that the protection word must be updated in all operating environments (DEV, OBD, PROG and IRE).

Example 1

Core boot block size is 4 Kbytes

—Bit 3-0 (Core Boot Block): 1110

●Shared BIOS using an expansion memory

—Bit 4 (Host Boot Block): 1

—Bit 6 (Force MBTA Zero): 0

●RTC may be accessed by the host (at default)

—Bit 5 (RTC Lock Default): 0

●Flash is not protected to allow debug

—Bits 9-7 (Flash Contents Protect): 111

●Use RESET2 on pin IOPB7/RING/PFAIL/RESET2

—Bits 15-14 (RST2EN): 01

The value that should be written to the protection word is 7F9E16 (binary 0111 1111 1001 1110).

Example 2

Same as Example 1, but for production version, once all debugging is completed. Change bits 9-7 from 111 to 000. Thus

the value that should be written to the protection word is 7C1E16 (binary 0111 1100 0001 1110).

Example 3

●Core boot block size is 8 Kbytes

—Bit 3-0 (Core Boot Block): 1101

●Shared BIOS using an expansion memory

—Bit 4 (Host Boot Block): 1

—Bit 6 (Force MBTA Zero): 0

●RTC may be accessed by the host (at default)

—Bit 5 (RTC Lock Default): 0

●Flash is not protected to allow debug

—Bits 9-7 (Flash Contents Protect): 111

●Use RESET2 on pin IOPD2/EXWINT24/RESET2

—Bits 15-14 (RST2EN): 10

The value that should be written to the protection word is BF9D16 (binary 1011 1111 1001 1101).

Example 4

●Core boot block size is 4 Kbytes

—Bit 3-0 (Core Boot Block): 1110

●Shared BIOS using an expansion memory

—Bit 4 (Host Boot Block): 1

—Bit 6 (Force MBTA Zero): 0

●After reset, RTC may be accessed only by the core, and host access is blocked until host access is enabled by the

core.

—Bit 5 (RTC Lock Default): 1

●Flash is not protected to allow debug

—Bits 9-7 (Flash Contents Protect): 111

●Do not use RESET2 (only RESET1 is in use)

—Bits 15-14 (RST2EN): 11

The value that should be written to the protection word is FFBE16 (binary 1111 1111 1011 1110)..

www.national.com 436 Revision1.07

PC87591E/S/L

Physical Dimensions inches (millimeters) unless otherwise noted

128-pin LQFP Package

Order Number: PC87591E-VLB/PC87591S-VLB

NS Package Number VLB128

PC87591E, PC87591S and PC87591L LPC Mobile Embedded Controllerswith SuperI/O Functions

National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.

LIFE SUPPORT POLICY

NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT

DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL

COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or

systems which, (a) are intended for surgical implant

into the body, or (b) support or sustain life, and whose

failure to perform, when properly used in accordance

with instructions for use provided in the labeling, can

be reasonably expected to result in a signiﬁcant injury

to the user.

2. A critical component is any component of a life

support device or system whose failure to perform can

be reasonably expected to cause the failure of the life

support device or system, or to affect its safety or

effectiveness.

National Semiconductor

Corporation

Americas

Email:

new.feedback@nsc.com

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Fax: +49 (0) 180-530 85 86

Email: europe.support@nsc.com

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Tel: 81-3-5639-7560

Fax: 81-3-5639-7507

Email: nsj.crc@jksmtp.nsc.com

176-Low Proﬁle Plastic Quad Flatpack (LQFP)

Order Number PC87591E-VPC/PC87591S-VPC/

PC87591L-VPC

NS Package Number VPC176