PRELIMINARY W79E225A/226A/227A DATA SHEET
8-bit Microcontroller
Publication Release Date: April 1 5, 2008
- 1 - Revision A4.0
Table of Contents-
1. GENERAL DESCRIPTION ......................................................................................................... 5
2. FEATURES................................................................................................................................. 6
3. PARTS INFORMATION LIST .....................................................................................................7
3.1 Lead Free (RoHS) Parts information list......................................................................... 7
4. PIN CONFIGURATION............................................................................................................... 8
5. PIN DESCRIPTION................................................................................................................... 10
5.1 Port 4 ............................................................................................................................ 12
6. MEMORY ORGANIZATION......................................................................................................13
6.1 Program Memory (on-chip Flash)................................................................................. 13
6.2 Data Memory ................................................................................................................ 13
6.3 Auxiliary SRAM.............................................................................................................14
6.4 NVM Data Flash............................................................................................................ 14
6.4.1 Operation........................................................................................................................19
7. SPECIAL FUNCTION REGISTERS .........................................................................................21
8. INSTRUCTION SET.................................................................................................................. 74
8.1 Instruction Timing.......................................................................................................... 84
8.1.1 External Data Memory Access Timing............................................................................86
9. POWER MANAGEMENT.......................................................................................................... 89
9.1 Idle Mode......................................................................................................................89
9.2 Power Down Mode ....................................................................................................... 89
10. RESET CONDITIONS............................................................................................................... 91
10.1 Sources of reset............................................................................................................91
10.1.1 External Reset..............................................................................................................91
10.1.2 Power-On Reset (POR)................................................................................................91
10.1.3 Watchdog Timer Reset.................................................................................................91
10.2 Reset State................................................................................................................... 92
11. INTERRUPTS........................................................................................................................... 93
11.1 Interrupt Sources .......................................................................................................... 93
11.2 Priority Level Structure .................................................................................................93
11.2.1 Response Time ............................................................................................................97
12. PROGRAMMABLE TIMERS/COUNTERS ...............................................................................98
12.1 Timer/Counters 0 & 1....................................................................................................98
12.1.1 Time-Base Selection ....................................................................................................98
12.1.2 Mode 0 .........................................................................................................................98
12.1.3 Mode 1 .........................................................................................................................99
12.1.4 Mode 2 .........................................................................................................................99
12.1.5 Mode 3 .......................................................................................................................100
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 2 - Revision A4.0
12.2 Timer/Counter 2..........................................................................................................100
12.2.1 Capture Mode.............................................................................................................101
12.2.2 Auto-reload Mode, Counting up..................................................................................101
12.2.3 Auto-reload Mode, Counting Up/Down.......................................................................102
12.2.4 Baud Rate Generator Mode .......................................................................................103
13. WATCHDOG TIMER...............................................................................................................104
14. PULSE-WIDTH-MODULATED (PWM) OUTPUTS.................................................................107
14.1 PWM Features............................................................................................................ 107
14.2 PWM Control Registers.............................................................................................. 108
14.3 PWM Pin Structures ...................................................................................................110
14.4 Complementary PWM with Dead-time and Override functions.................................. 113
14.5 Dead-Time Insertion...................................................................................................114
14.6 PWM Output Override ................................................................................................115
14.7 Edge Aligned PWM (up-counter)................................................................................118
14.8 Center Aligned PWM (up/down counter)....................................................................121
14.9 Single Shot (Up-Counter) ...........................................................................................123
14.10 Smart Fault Detector .............................................................................................. 126
14.11 PWM Power-down/Wakeup Procedures................................................................ 128
15. MOTION FEEDBACK MODULE.............................................................................................130
15.1 Input Capture Module (IC)..........................................................................................130
15.1.1 Compare Mode...........................................................................................................138
15.1.2 Reload Mode..............................................................................................................138
15.2 Quadrature Encoder Interface (QEI) .......................................................................... 138
15.2.1 Free-counting mode ...................................................................................................140
15.2.2 Compare-counting mode............................................................................................140
15.2.3 X2/X4 Counting modes...............................................................................................140
15.2.4 Direction of Count.......................................................................................................140
15.2.5 Up-Counting ...............................................................................................................142
15.2.6 Down-Counting...........................................................................................................142
16. SERIAL PORT ........................................................................................................................ 143
16.1 Mode 0........................................................................................................................143
16.2 Mode 1........................................................................................................................144
16.3 Mode 2........................................................................................................................145
16.4 Mode 3........................................................................................................................146
16.5 Framing Error Detection .............................................................................................147
16.6 Multiprocessor Communications.................................................................................147
17. I2C SERIAL PORTS ...............................................................................................................149
17.1 SIO Port......................................................................................................................149
17.2 The I2C Control Registers..........................................................................................149
17.2.1 Slave Address Registers, I2ADDR.............................................................................150
17.2.2 Data Register, I2DAT .................................................................................................150
17.2.3 Control Register, I2CON.............................................................................................150
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 3 - Revision A4.0
17.2.4 Status Register, I2STATUS........................................................................................151
17.2.5 I2C Clock Baud Rate Control, I2CLK..........................................................................151
17.2.6 I2C Time-out Counter, I2Timer...................................................................................151
17.2.7 I2C Maskable Slave Address .....................................................................................152
17.3 Modes of Operation.................................................................................................... 152
17.3.1 Master Transmitter Mode ...........................................................................................152
17.3.2 Master Receiver Mode ...............................................................................................152
17.3.3 Slave Receiver Mode .................................................................................................153
17.3.4 Slave Transmitter Mode .............................................................................................153
17.4 Data Transfer Flow in Five Operating Modes............................................................. 153
17.4.1 Master/Transmitter Mode ...........................................................................................154
17.4.2 Figure 17-5: Master Transmitter ModeMaster/Receiver Mode ...................................155
17.4.3 Slave/Transmitter Mode .............................................................................................156
17.4.4 Slave/Receiver Mode .................................................................................................157
17.4.5 GC Mode....................................................................................................................158
18. SERIAL PERIPHERAL INTERFACE (SPI).............................................................................159
18.1 General descriptions...................................................................................................159
18.2 Block descriptions.......................................................................................................159
18.3 Functional descriptions...............................................................................................161
18.3.1 Master mode ..............................................................................................................161
18.3.2 Slave Mode ................................................................................................................164
18.3.3 Slave select................................................................................................................168
18.3.4 /SS output...................................................................................................................168
18.3.5 SPI I/O pins mode ......................................................................................................169
18.3.6 Programmable serial clock’s phase and polarity ........................................................170
18.3.7 Receive double buffered data register........................................................................171
18.3.8 LSB first enable..........................................................................................................172
18.3.9 Write Collision detection.............................................................................................172
18.3.10 Transfer complete interrupt ......................................................................................172
18.3.11 Mode Fault ...............................................................................................................172
19. ANALOG-TO-DIGITAL CONVERTER.................................................................................... 175
19.1 Operation of ADC .......................................................................................................175
19.2 ADC Resolution and Analog Supply........................................................................... 176
20. TIMED ACCESS PROTECTION ............................................................................................177
21. PORT 4 STRUCTURE............................................................................................................179
22. IN-SYSTEM PROGRAMMING................................................................................................182
22.1 The Loader Program Locates at LDFlash Memory .................................................... 182
22.2 The Loader Program Locates at APFlash Memory.................................................... 182
23. OPTION BITS ......................................................................................................................... 183
23.1 Config0........................................................................................................................ 183
23.2 Config1........................................................................................................................ 184
24. ELECTRICAL CHA RACTERISTICS.......................................................................................185
24.1 Absolute Maximum Ratings........................................................................................ 185
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 4 - Revision A4.0
24.2 DC Characteristics...................................................................................................... 185
24.3 AC Characteristics...................................................................................................... 188
24.3.1 External Clock Characteristics....................................................................................188
24.3.2 AC Specification.........................................................................................................188
24.3.3 MOVX Characteristics Using Stretch Memory Cycle..................................................189
24.4 The ADC Converter DC ELECTRICAL CHA RA CTERISTICS ...................................191
24.5 I2C Bus Timing Characteristics ..................................................................................191
24.6 Program Memory Read Cycle .................................................................................... 192
24.7 Data Memory Read Cycle...........................................................................................193
24.8 Data Memory Write Cycle...........................................................................................193
25. TYPICAL APPLICATION CIRCUITS......................................................................................194
25.1 Expanded External Program Memory and Crystal..................................................... 194
25.2 Expanded External Data Memory and Oscillator........................................................194
26. PACKAGE DIMENSION .........................................................................................................195
26.1 44L PLCC ................................................................................................................... 195
26.2 48L LQFP (7x7x1.4mm footprint 2.0mm)................................................................... 196
27. APPLICATION NOTE ............................................................................................................. 197
28. REVISION HISTORY..............................................................................................................203
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 5 - Revision A4.0
1. GENERAL DESCRIPTION
The W79E22X SERIES is a fast, 8051/52-compatible microcontroller with a redesigned processor
core that eliminates wasted clock and memory cycles. Typically, the W79E22X SERIES executes
instructions 1.5 to 3 times faster than that of the traditional 8051/52, depending on the type of
instruction, and the overall performance is about 2.5 times better at the same crystal speed. As a
result, with the fully-static CMOS design, the W79E22X SERIES can accomplish the same throughput
with a lower clock speed, reducing power co nsumption.
The W79E22X SERIES provides 256 bytes of on-chip RAM; 1/2/2-KB of NVM Data Flash EPROM;
1/2/2-KB of auxiliary RAM; four 8-bit, bi-directional and bit-addressable I/O ports; an additional 4-bit
port P4 and 2-bit port P5; three 16-bit timer/counters; Motion Feedback Module support; 2 UART
serial ports; 1 channels of I2C with master/slave capability; 1 channels of Serial Peripheral Interface
(SPI), 8 channels of 12 bit PWM with configurable dead time and 8 channels of 10-bit ADC. These
peripherals are all supported by 20 interrupt sources with 4 levels of priority.
The W79E22X SERIES also contains a 16/32/64-KB Flash EPROM whose contents may be updated
in-system by a loader program stored in an auxiliary, 4-KB Flash EPROM. Once the contents are
confirmed, it can be protected for security.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 6 - Revision A4.0
2. FEATURES
z Fully-static-design 8-bit 4T -8051 CMOS microcontroller up to 40MHz.
z 16/32/64-KB of in-system-programm able Flash EPROM (AP Flash EPROM).
z 4-KB of Auxiliary Flash EPROM for the loader program (LD Flash EPROM). User can optionally
reboot from LD Flash EPROM by pull low at either P4.3 or P3.6 and P3.7, at external reset.
z 1/2/2-KB auxiliary RAM, software-selectable, accessed by MOVX instruction.
z 1/2/2-KB of NVM Data Flash EPROM for customer data storage used.
z 256 bytes of scratch-pad RAM.
z Four 8-bit bi-directional ports; Port 0 has internal pull-up resisters enabled by software.
z Multipurpose I/O port4 (4 bits for 48L LQFP; 2 bits for 44L PLCC) with Chips select (CS) and
boot function.
z Two bits bi-directional port5.
z Three 16-bit timers.
z One 16-bit Timer 3 for Motion Feed-Back Module.
z Motion Feedback Module - QEI decoder and 3 Inputs Capture.
z Eight channels of 12-bit PWM:-
　 − Complementary paired output with pro grammable dead-time insertion.
　 − Three modes: Edge aligned, cente r aligned and single shot.
　 − Output override control for BLDC m otor application.
z 10-bit ADC with 8-channel inputs.
z Two enhanced full-dupl ex UART with framing-error detection and automatic address re cognition.
z One channel of I2C with master/ slave capability.
z One channel of SPI with master/slave capability.
z Software programmable access cy cle to external RAM/peripherals.
z 20 interrupt sources with four levels of priority.
z Software reset function.
z Optional H/L state of ALE/PSEN during power down mode.
z Built-in power management.
z Code protection.
z Package:
　 − Lead Free (RoHS) PLCC 44: W79E225APG
　 − Lead Free (RoHS) LQFP 48: W79E225AFG
　 − Lead Free (RoHS) PLCC 44: W79E226APG
　 − Lead Free (RoHS) LQFP 48: W79E226AFG
　 − Lead Free (RoHS) PLCC 44: W79E227APG
　 − Lead Free (RoHS) LQFP 48: W79E227AFG
　
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 7 - Revision A4.0
3. PARTS INFORMATION LIST
3.1 Lead Free (RoHS) Parts information list
PART NO.
EPROM
FLASH
SIZE
RAM OPERATING
FREQUENCY
OPERATING
VOLTAGE
NVM
FLASH
EPROM
PACKAGE REMARK
up to 40MHz
up to 20MHz 4.5V ~ 5.5V
2.7V[1] ~ 5.5V Internal
memory
W
79E225APG 16KB
256B
+
1KB up to 24MHz 4.5V ~ 5.5V 1KB PLCC-44 Pin
External
memory
up to 40MHz
up to 20MHz 4.5V ~ 5.5V
2.7V[1] ~ 5.5V Internal
memory
W
79E225AFG 16KB 256B+
1KB up to 24MHz 4.5V ~ 5.5V 1KB LQFP-48 Pin
External
memory
up to 40MHz
up to 20MHz 4.5V ~ 5.5V
2.7V[1] ~ 5.5V Internal
memory
W
79E226APG 32KB
256B
+
2KB up to 24MHz 4.5V ~ 5.5V 2KB PLCC-44 Pin
External
memory
up to 40MHz
up to 20MHz 4.5V ~ 5.5V
2.7V[1] ~ 5.5V Internal
memory
W
79E226AFG 32KB
256B
+
2KB up to 24MHz 4.5V ~ 5.5V 2KB LQFP-48 Pin
External
memory
up to 40MHz
up to 20MHz 4.5V ~ 5.5V
2.7V[1] ~ 5.5V Internal
memory
W
79E227APG 64KB
256B
+
2KB up to 24MHz 4.5V ~ 5.5V 2KB PLCC-44 Pin
External
memory
up to 40MHz
up to 20MHz 4.5V ~ 5.5V
2.7V[1] ~ 5.5V Internal
memory
W
79E227AFG 64KB
256B
+
2KB up to 24MHz 4.5V ~ 5.5V 2KB LQFP-48 Pin
External
memory
Note: 1. Minimum of 3.0V operating voltage for NVM program and erase operations.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 8 - Revision A4.0
4. PIN CONFIGURATION
13 14 15 16 17 18 19 20 21 22 25
26
27
28
29
30
31
32
33
44 43 42 41 40 39 38 37
11
10
9
8
7
6
5
4
3
2
1
W79E225
W79E226
W79E227
(LQFP 48-Pin)
XTAL2
XTAL1
P3.1, TXD
P3.0, RXD
VDD
ALE 12 23 24
34
35
36
45464748
VSS
P4.2
P4.3
MISO, AD0, P0.0
MOSI, AD1, P0.1
SPCLK, AD2, P0.2
INT2, AD4, P0.4
INT3, AD5, P0.5
INT4, AD6, P0.6
INT5, AD7, P0.7
P3.4, T0, IC0, QEA
P3.5, T1, IC1, QEB
SS, AD3, P0.3
EA
P3.2, INT0
P3.3, INT1
P3.6, WR
P3.7, RD
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 9 - Revision A4.0
18 19 20 21 22 23 24 25 26 27 28
29
30
31
32
33
34
35
36
37
38
39
6 5 4 3 2 1 44 43 42 41 40
17
16
15
14
13
12
11
10
9
8
7
W79E225
W79E226
W79E227
(PLCC 44-Pin)
XTAL1
ALE
STADC, P4.0
ADC7, P1.7
ADC6, P1.6
ADC5, P1.5
ADC4, P1.4
RXD1, ADC2, P1.2
BRAKE, ADC1, P1.1
T2, ADC0, P1.0
TXD1, ADC3, P1.3
AVSS
AVDD
P3.1, TXD
P3.0, RXD
RST
P4.1, T2EX, IC2, INDX
P2.0, A8, PWM0
VDD
P2.1, A9, PWM1
P2.2, A10, PWM2
P2.3, A11, PWM3
P2.4, A12, PWM4
P2.5, A13, PWM5
P2.6, A14, SCL
P2.7, A15, SDA
VSS
XTAL2
P3.4, T0, IC0, QEA
P3.5, T1, IC1, QEB
MISO, AD0, P0.0
MOSI, AD1, P0.1
SPCLK, AD2, P0.2
INT2, AD4, P0.4
INT3, AD5, P0.5
INT4, AD6, P0.6
INT5, AD7, P0.7
SS, AD3, P0.3
PSEN
EA
P3.2, INT0
P3.3, INT1
P3.6, WR
P3.7, RD
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 10 - Revision A4.0
5. PIN DESCRIPTION
SYMBOL TYPE
INITIAL
STATE DESCRIPTIONS
EA I -
EXTERNAL ACCESS ENABLE: This pin forces the processor to
execute from external ROM. The ROM address and data are not
presented on the bus if the EA pin is high.
Note: This pin has no internal pull-up or pull-down. The pin
needs externally pull-up to execute from internal APROM. For
executing from external APROM, the pin needs externally pull-
down. The pin state is internally latched during all reset. User
needs to take note that changes to /EA pin state after reset will
not be effective.
PSEN O H High PROGRAM STORE ENABLE: PSEN enables the external ROM
data in the Port 0 address/data bus. When internal ROM access is
performed, PSEN strobe signal will not be output from this pin.
ALE O H High ADDRESS LATCH ENABLE: ALE enables the address latch that
separates the addres s from the data on Port 0.
RST I L - RESET: Set this pin high for two machine cycles while the
oscillator is running to reset the device.
XTAL1 I - CRYSTAL 1: Crystal oscillator input or external cl ock input.
XTAL2 O - CRYSTAL 2: Crystal oscillator output.
VSS I - GROUND: Ground potential.
VDD I - POWER SUPPLY: Supply voltage for operation.
AVDD I - Analog power supply.
AVSS I - Analog ground potential.
P0.0−P0.7 I/O
D S H High-Z
PORT 0: Port 0 is an open-drain bi-directional I/O port. This port
also provides a multiplexed low byte address/data bus during
accesses to external memory. There is an embedded weakly pull-
up resistor on each port 0 pin which can be enabled or disabled by
setting or clearing of PUP0, bit0 in A2h. The ports have alternate
functions which are described below:
P0.0, AD0, MISO
P0.1, AD1, MOSI
P0.2, AD2, SPCLK
P0.3, AD3, /SS
P0.4, AD4, INT2
P0.5, AD5, INT3
P0.6, AD6, INT4
P0.7, AD7, INT5
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 11 - Revision A4.0
PIN DESCRIPTION, continued
SYMBOL TYPE
INITIAL
STATE DESCRIPTIONS
P1.0−P1.7 I/O S H High
PORT 1: 8-bit, bi-directional I/O port with internal pull-ups. The
ports have alternate functions which are described below:
P1.0, ADC0, T2
P1.1, ADC1, BRAKE
P1.2, ADC2, RXD1
P1.3, ADC3, TXD1
P1.4, ADC4
P1.5, ADC5
P1.6, ADC6
P1.7, ADC7
P2.0-P2.5 I/O S Tri-state
P2.6-P2.7 I/O D High-Z
PORT 2: 8-bit, bi-directional I/O port. This port also provides the
upper address bits for accesses to external memory. P2.6 to P2.7
can be software configured as I2C serial ports. P2.0 to P2.5 also
provides PWM0 to PWM5 outputs.
P2.0, A8, PWM0
P2.1, A9, PWM1
P2.2, A10, PWM2
P2.3, A11, PWM3
P2.4, A12, PWM4
P2.5, A13, PWM5
P2.6, A14, SCL
P2.7, A15, SDA
Note:
P2.6 and P2.7 are permanent open drain pins. When access to
external memory beyond 16K region, user requires to add
external pull-up registers (up to 2Kohm) on these pins. This
will result in slight increase in current consumption.
P3.0-P3.7 I/O S H High
PORT 3: 8-bit, bi-directional I/O port with internal pull-ups. The
ports have alternate functions which are described below:
P3.0, RXD
P3.1, TXD
P3.2, /INT0
P3.3, /INT1
P3.4, T0, IC0, QEA
P3.5, T1, IC1, QEB
P3.6, /WR
P3.7, /RD
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 12 - Revision A4.0
PIN DESCRIPTION, continued
SYMBOL TYPE
INITIAL
STATE DESCRIPTIONS
P4.0-P4.3 I/O S H High
PORT 4: 4-bit multipurpose programmable I/O port with alternate
functions. The Port 4 has four different operation modes.
P4.0, STADC
P4.1, T2EX, IC2
P4.2
P4.3
Note: P4.2 & P4.3 are not supported in PLCC44 pins package.
P5.0-P5.1 I/O S Tri-state
PORT 5: 2-bit, bit-directional I/O port. This port is not bit
addressable. The alternate functions are described below:
P5.0, PWM6
P5.1, PWM7
Note: P5.0 & P5.1 are not supported in PLCC44 pins package.
Note ：TYPE I: input, O: output, I/O: bi-directional, H: pull-high, L: pull-low, D: open drain S: Schmitt Trigger
5.1 Port 4
Port 4, SFR P4 at address A5H, is a 4-bit multipurpose programmable I/O port which functions are I/O
and chip-select function. It has four different operation modes:
z Mode 0 - P4.0 ~ P4.3 is 4-bit bi-directional I/O port which is the same as port 1. The default Port
4 is a general I/O function.
z Mode1 - P4.0 ~ P4.3 are read data strobe signals which are synchronized with RD signal at
specified addresses. These read data strobe signals can be used as chip-select signals for
external peripherals.
z Mode2 - P4.0 ~ P4.3 are write data strobe signals which are synchronized with WR signal at
specified addresses. These write data strobe signals can be used as chip-select signals for
external peripherals.
z Mode3 - P4.0 ~ P4.3 are read/write data strobe signals which are synchronized with RD
orWR signal at specified addresses. These read/write data strobe signals can be used as chip-
select signals for external periph erals.
When Port 4 is configured with the feature of chip-select signals, the chip-select signal address range
depends on the contents of the SFR P4xAH, P4xAL, P4CONA and P4CONB. P4xAH and P4xAL
contain the 16-bit base address of P4.x. P4CONA and P4CONB contain the control bits to configure
the Port 4 operation mode.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 13 - Revision A4.0
6. MEMORY ORGANIZATION
The W79E22X SERIES separates the memory into two sections; Program Memory and Data Memory.
Program Memory stores instruction op-codes, while Data Memory stores data or memory-mapped
devices.
6.1 Program Memory (on-chip Flash)
W79E22X SERIES includes one 16/32/64K bytes of main FLASH EPROM for application program (AP
FLASH EPROM) and one 4K bytes of FLASH EPROM for loader program (LD FLASH EPROM) to
operate the in-system programming (ISP) feature, and one 1/2/2K bytes of NVM Flash EPROM for
data storage. The 16/32/64K bytes Flash EPROM is AP0 bank. The default active bank is AP0.
In normal operation, the microcontroller will execute the code from main FLASH EPROM. By setting
program registers, user can force the microcontroller to switch to programming mode which will cause
it to execute the code (loader program) from the 4K bytes of auxiliary LD FLASH EPROM to update
the contents of the 16/32/64K bytes of main FLASH EPROM. After reset, the microcontroller will
executes the new application program in the main FLASH EPROM. This ISP feature makes the job
easy and efficient in which the application needs to update firmware frequently without opening the
chassis.
6.2 Data Memory
W79E22X SERIES can access up to 64Kbytes of external Data Memory. This memory region is
accessed by the MOVX instructions. Unlike the 8051 derivatives, W79E22X SERIES contains on-chip
1/2/2 Kbytes of Data Memory, which only can be accessed by MOVX instructions. These 1/2/2 Kbytes
of SRAM is between address 0000h and 03FFH/07FFH. Access to the on-chip Data Memory is
optional under software control. When enabled by DMEO bit of PMR register, a MOVX instruction that
uses this area will go to the on-chip RAM. If MOVX instruction accesses the addresses greater than
03FFH/07FFH CPU will automatically access external memory through Port 0 and 2. When disabled,
the 1/2/2 KB memory area is transparent to the system memory map. Any MOVX directed to the
space between 0000h and FFFFH goes to the expanded bus on the Port 0 and 2. This is the default
condition. In addition, the device has the standard 256 bytes of on-chip RAM. This can be accessed
either by direct addressing or by indirect addressing. There are also some Special Function Registers
(SFRs), which can only be accessed by direct addressing.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 14 - Revision A4.0
Figure 6-1: W79E22X SERIESA Memory Map
6.3 Auxiliary SRAM
W79E22X SERIES has a 1/2/2 KB of data space SRAM which is read/write accessible and is memory
mapped. This on-chip SRAM is accessed by the MOVX instruction. There is no conflict or overlap
among the 256 bytes scratch-pad memory and the 1/2/2 KB auxiliary sram as they use different
addressing modes and instructions. Access to the on-chip Data Memory is optional under software
control. Set DMEO bit of PMR SFR to 1 will enable the on-chip 1/2/2 KB MOVX SRAM and at the
same time EnNVM bit must be cleared as NVM Data uses the same instruction of MOVX. Refer to.
6.4 NVM Data Flash
W79E22X SERIES 1/2/2-KB NVM Data block shown in the diagram on Figure 6-1 shares the same
address as AUX-RAM address.
Due to overlapping of AUX-RAM, NVM data memory and external data memory physical address, the
following table is defined. EnNVM bit (NVMCON.5) will enable read access to NVM data flash area.
DME0 (PMR.0) will enable read access to AUX-RAM.
ENNVM DME0 DATA MEMORY AREA
0 0 Enable External RAM read/write access by MOVX
0 1 Enable AUX-RAM read/write access by MOVX
1 X
Enable NVM data Memory read access by MOVX only. If EER or
EWR is set and NVM flash erase or write control is busy, to set
this bit read NVM data is invalid.
Table 6-1: Bits setting for MOVX access to Data Memory Area
ENNVM = 1 INSTRUCTIONS
NVM SIZE = SRAM (1K)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 15 - Revision A4.0
ADDR ≤ 1K ADDR > 1K
MOVX A, @DPTR (Read) NVM1 Ext memory1
MOVX A, @R0 (Read) NVM2 NOP
Read
access MOVX A, @R1 (Read) NVM2 NOP
MOVX @DPTR, A (Write) NOP Ext memory1
MOVX @R0, A (Write) NOP NOP
Write
access MOVX @R1, A (Write) NOP NOP
Table 6-2: W79E225 MOVX read/write access destination
ENNVM = 1
NVM SIZE = SRAM (2K)
INSTRUCTIONS
ADDR ≤ 2K ADDR > 2K
MOVX A, @DPTR (Read) NVM1 Ext memory1
MOVX A, @R0 (Read) NVM2 NOP
Read
access MOVX A, @R1 (Read) NVM2 NOP
MOVX @DPTR, A (Write) NOP Ext memory1
MOVX @R0, A (Write) NOP NOP
Write
access MOVX @R1, A (Write) NOP NOP
Table 6-3: W79E226/227 MOVX read/write access destination
Note:
1. A15~A0=DPTR
2. A15~A8=XRAMAH
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 16 - Revision A4.0
It is partition into 16/32/32 pages area and each page has 64 bytes data as below figure. The page 0
is from 0000h ~ 003Fh, page 1 is from 0040h ~ 007Fh until page 31 address located at 07COh ~
07FFh.
Figure 6-2: W79E225 NVM Data Mapping
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 17 - Revision A4.0
2K Bytes Flash
EPROM
Page 31
64Bytes
Page 30
64Bytes
|
|
|
|
|
|
Page 03
64Bytes
Page 02
64Bytes
Page 01
64Bytes
Page 00
64Bytes
07FFH
07C0H
07BFH
0780H
0000H
003FH
0040H
007FH
0080H
00BFH
00C0H
00FFH
0000H
07FFH
Figure 6-3: W79E226/227 NVM Data Mapping
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 18 - Revision A4.0
PAGE START ADDRESS END ADDRESS PAGE START ADDRESS END ADDRESS
0 0000h 003Fh 16 0400h 043Fh
1 0040h 007Fh 17 0440h 047Fh
2 0080h 00BFh 18 0480h 04BFh
3 00C0h 00FFh 19 04C0h 04FFh
4 0100h 013Fh 20 0500h 053Fh
5 0140h 017Fh 21 0540h 057Fh
6 0180h 01BFh 22 0580h 05BFh
7 01C0h 01FFh 23 05C0h 05FFh
8 0200h 023Fh 24 0600h 063Fh
9 0240h 027Fh 25 0640h 067Fh
10 0280h 02BFh 26 0680h 06BFh
11 02C0h 02FFh 27 06C0h 06FFh
12 0300h 033Fh 28 0700h 073Fh
13 0340h 037Fh 29 0740h 077Fh
14 0380h 03BFh 30 0780h 07BFh
15 03C0h 03FFh 31 07C0h 07FFh
[Note: Page 16-31 is for W79E226/227 only]
Table 6-4: W79E22X SERIES NVM page (n) area definition table
It has a dedicated On-Chip RC Oscillator that is fixed at 6MHz +/- 25% frequency to support clock
source for the 1/2/2K NVM data Flash. The on chip oscillator is enabled only during program or erase
operation, through EWR or EER in NVMCON SFR. EWR or EER bits are cleared by hardware after
program or erase operation completed. The program/erase time is automatically controlled by
hardware.
Figure 6-4: NVM control
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 19 - Revision A4.0
6.4.1 Operation
User is required to enable EnNVM (NVMCON.5) bit for all NVM ac cess (read/write/erase).
Before write data to NVM Data, the page must be erased. A page is erased by setting page address
which address will decode and enable page (n) on NVMADDRH and NVMADDRL, then set EER
(NVMCON.7) and EnNVM (NVMCON.5). The device will then automatic execute page erase. When
completed, NVMF will be set by hardware. NVMF should be cleared by software. Interrupt request will
be generated if ENVM (EIE1.5) is enabled. EER bit will be cleared by hardware when erase is
completed. The total erase time is about 5ms.
For write, user must set address and data to NVMADDRH/L and NVMDAT, respectively. And then set
EWR (NVMCON.6) and EnNVM (NVMCON.5) to enable data write. When completed, the device will
set NVMF flag. NVMF flag should be cleared by software. Similarly, interrupt request will be generated
if ENVM (EIE1.5) is enabled. The program time is about 50us.
The following shows some examples of NVM operations (using W79E226/227):
Read NVM data is by MOVX A,@DPTR/R0/R1 instruction:
A read exceed 2k will read the external address
Example1: DPTR=0x07FF, R0/R1 = 0xFF, XRAMAH=0x07, EnNVM=1
MOVX A,@DPTR Æ read NVM data at address 0x07FF
MOVX A,@R0 Æ read NVM data at address 0x07 FF
MOVX A,@R1 Æ read NVM data at address 0x07 FF
Example2: DPTR = 0x2000, EnNVM=1, DME0=0
MOVX A,@DPTR Æ read external RAM data at address 0x2000,
Erase NVM by SFR register:
Example1: NVMADDRH = 0x07, NVMADDRL = 0xF0, page 31 will be enabled. After set EER, the
page 31 will be erased.
Example2: NVMADDRH = 0x10, NVMADDRL = 0x00, invalid NVM erase instruction (address exceed
NVM boundary).
Write NVM by SFR register:
Example1: NVMADDRH = 0x07, NVMADDRL = 0xF0
After set EWR, data will be written to the NVM address = 0x07F0 location.
Example2: NVMADDRH = 0x10, NVMADDRL = 0x00, after set EWR, invalid NVM write instruction
(address exceed NVM boundary).
During erase, write is invalid. Likewise, during write, erase is invalid. An erase or write is invalid if
NVMF is not clear by software. A write to NVMADDRH and NVMADDRL is invalid during Erase or
Write, and a write to NVMDAT is invalid only during NVM write a c cess.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 20 - Revision A4.0
Figure 6-5: NVM data memory control timing
For security purposes, this NVM data flash provides an independent “Lock bit” located in Security bits.
It is used to protect the customer’s 1/2/2K bytes of data code. It may be enabled after the external
programmer finishes the programming and verifying sequence. Once this bit is set to logic 0, the
1/2/2K bytes of NVM Flash EPROM data can not be accessed again by external device.
Note: 1. NVMF can be polled or by h/w interrupt to indicate NVM data memory erase or write
operation has completed.
2. While user program is erasing or writing to NVM data memory, the PC counter will continue
to fetch for next instruction.
3. When uC is in idle mode and if NVM interrupt and global interrupt are enabled, the
completion of either erasing or programming the NVM data memory will exit the idle
condition.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 21 - Revision A4.0
7. SPECIAL FUNCTION REGISTERS
The W79E22X SERIES uses Special Function Registers (SFR) to control and monitor peripherals.
The SFR reside in register locations 80-FFh and are only accessed by direct addressing. The
W79E22X SERIES contains all the SFR present in the standard 8051/52, as well as some additional
SFR, and, in some cases, unused bits in the standard 8051/52 have new functions. SFR whose
addresses end in 0 or 8 (hex) are bit-addressable. The following table of SFR is condensed, with eight
locations per row. Empty lo cat i ons indicate that there are no registers at these ad dresses.
F8 EIP EIE1 EIP1 CCL0
/PCNTL CCH0
/PCNTH CCL1
/PLSCNTL CCH1
/PLSCNTH INTCTRL
F0 B SPCR SPSR SPDR I2CSADEN EIPH
E8 EIE I2CON I2ADDR NVMADDRH I2DAT I2STATUS I2CLK I2TIMER
E0 ACC ADCCON ADCH ADCL PDTC1 PDTC0 PWMCON4
D8 WDCON PWMPL PWM0L NVMADDRL PWMCON1 PWM2L PWM6L PWMCON3
D0 PSW PWMPH PWM0H NVMDAT QEICON PWM2H PWM6H WDCON2
C8 T2CON T2MOD RCAP2L RCAP2H TL2 TH2 PWMCON2 PWM4L
C0 SCON1 SBUF1 T3MOD T3CON PMR FSPLT ADCPS TA
B8 IP SADEN SADEN1 POVM POVD PIO PWMEN PWM4H
B0 P3 P5 RCAP3L RCAP3H EIP1H IPH
A8 IE SADDR SADDR1 SFRAL SFRAH SFRFD SFRCN
A0 P2 XRAMAH P4CSIN CAPCON0 CAPCON1 P4 CCL2
/MAXCNTL CCH2
/MAXCNTH
98 SCON SBUF P42AL P42AH P43AL P43AH NVMCON CHPCON
90 P1 EXIF P4CONA P4CONB P40AL P40AH P41AL P41AH
88 TCON TMOD TL0 TL1 TH0 TH1 CKCON CKCON1
80 P0 SP DPL DPH TL3 TH3 PCON
Table 7-1: Special Function Register Location Table
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 22 - Revision A4.0
SYMBOL DEFINITION ADD
RESS
MSB BIT_
A
DDRESS, SYMBOL
LSB RESET
INTCTRL INTERRUPT CONTROL
REGISTER FFH - - INT5CT1 INT5CT0 INT4CT1 INT4CT0 INT3CT1 INT3CT0 xx00 0000
B
CCH1
/PLSCNTH CAPTURE COUNTER HIGH
1 REGISTER FEH CCH1.7
/PLSCN
TH.7
CCH1.6
/PLSCN
TH.6
CCH1.5
/PLSCN
TH.5
CCH1.4
/PLSCN
TH.4
CCH1.3
/PLSCN
TH.3
CCH1.2
/PLSCN
TH.2
CCH1.1
/PLSCN
TH.1
CCH1.0
/PLSCN
TH.0 0000 0000
B
CCL1
/PLSCNTL CAPTURE COUNTER LOW 1
REGISTER FDH CCL1.7
/PLSCN
TL.7
CCL1.6
/PLSCN
TL.6
CCL1.5
/PLSCN
TL.5
CCL1.4
/PLSCN
TL.4
CCL1.3
/PLSCN
TL.3
CCL1.2
/PLSCN
TL.2
CCL1.1
/PLSCN
TL.1
CCL1.0
/PLSCN
TL.0 0000 0000
B
CCH0
/PCNTH CAPTURE COUNTER HIGH
0 REGISTER FCH CCH0.7
/PCNTH.
7
CCH0.6
/PCNTH.
6
CCH0.5
/PCNTH.
5
CCH0.4
/PCNTH.
4
CCH0.3
/PCNTH.
3
CCH0.2
/PCNTH.
2
CCH0.1
/PCNTH.
1
CCH0.0
/PCNTH.
0 0000 0000
B
CCL0
/PCNTL CAPTURE COUNTER LOW 0
REGISTER FBH CCL0.7
/PCNTL.
7
CCL0.6
/PCNTL.
6
CCL0.5
/PCNTL.
5
CCL0.4
/PCNTL.
4
CCL0.3
/PCNTL.
3
CCL0.2
/PCNTL.
2
CCL0.1
/PCNTL.
1
CCL0.0
/PCNTL.
0 0000 0000
B
EIP1 EXTENDED INTERRUPT
PRIORITY 1 FAH - - PNVMI PCPTF PT3 PBKF PPWMF PSPI xx00 0000
B
EIE1 INTERRUPT ENABLE 1 F9H - - ENVM ECPTF ET3 EBK EPWM ESPI xx00 0000
B
EIP EXTENDED INTERRUPT
PRIORITY F8H (FF)
PS1 (FE)
PX5 (FD)
PX4 (FC)
PWDI (FB)
PX3 (FA)
PX2 (F9)
- (F8)
PI2C 0000 00x0
B
EIPH EXTENDED INTERRUPT
HIGH PRIORITY F7H PS1H PX5H PX4H PWDIH PX3H PX2H - PI2CH 0000 00x0
B
I2CSADEN I2C SLAVE ADDRESS MASK F6H I2CSAD
EN.7 I2CSAD
EN.6 I2CSAD
EN.5 I2CSAD
EN.4 I2CSAD
EN.3 I2CSAD
EN.2 I2CSAD
EN.1 I2CSAD
EN.0 1111 1110
B
SPDR SERIAL PERIPHERAL DATA
REGISTER F5H SPD.7 SPD.6 SPD.5 SPD.4 SPD.3 SPD.2 SPD.1 SPD.0 xxxx xxxxB
SPSR SERIAL PERIPHERAL
STATUS REGISTER F4H SPIF WCOL SPIOVF MODF DRSS - - - 0000 0xxxB
SPCR SERIAL PERIPHERAL
CONTROL REGISTER F3H SSOE SPE LSBFE MSTR CPOL CPHA SPR1 SPR0 0000 0100
B
B B REGISTER F0H (F7) (F6) (F5) (F4) (F3) (F2) (F1) (F0) 0000 0000
B
I2TIMER I2C TIMER COUNTER
REGISTER EFH - - - - - ENTI DIV4 TIF xxxx x000B
I2CLK I2C CLOCK RATE EEH I2CLK.7 I2CLK.6 I2CLK.5 I2CLK.4 I2CLK.3 I2CLK.2 I2CLK.1 I2CLK.0 0000 0000
B
I2STATUS I2C STATUS REGISTER EDH I2STATU
S.7 I2STATU
S.6 I2STATU
S.5 I2STATU
S.4 I2STATU
S.3 - - - 1111 1000
B
I2DAT I2C DATA ECH I2DAT.7 I2DAT.6 I2DAT.5 I2DAT.4 I2DAT.3 I2DAT.2 I2DAT.1 I2DAT.0 0000 0000
B
VMADDR
NVM HIGH BYTE ADDRESS EBH - - - -
- NVMAD
DRH.10 NVMAD
DRH.9 NVMAD
DRH.8 xxxx x000B
I2ADDR I2C SLAVE ADDRESS EAH ADDR.7 ADDR.6 ADDR.5 ADDR.4 ADDR.3 ADDR.2 ADDR.1 GC 0000 0000
B
I2CON I2C CONTROL REGISTER E9H - ENS STA STO SI AA I2CIN - X000 000x
B
EIE EXTENDED INTERRUPT
ENABLE E8H (EF)
ES1 (EE)
EX5 (ED)
EX4 (EC)
EWDI (EB)
EX3 (EA)
EX2 (E9)
(E8)
EI2C 0000 00x0
B
PWMCON4 PW M CONTROL REGISTER
4 E7H PWMEO
M PWMOO
M PWM6O
M PWM7O
M - - - BKF 0000 xxx0B
PDTC0 DEAD TIME CONTROL
REGISTER 0 E6H PDTC0.7 PDTC0.6 PDTC0.5 PDTC0.4 PDTC0.3 PDTC0.2 PDTC0.1 PDTC0.0 0000 0000
B
PDTC1 DEAD TIME CONTROL
REGISTER 1 E5H PDTC1.7 PDTC1.6 PDTC1.5 PDTC1.4 PDTC1.3 PDTC1.2 PDTC1.1 PDTC1.0 0000 0000
B
ADCL ADC CONVERTER RESULT
LOW BYTE E3H ADCLK1 ADCLK0 - - - - ADC.1 ADC.0 00xx xxxxB
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 23 - Revision A4.0
Continued
SYMBOL DEFINITION ADDR
ESS
MSB BIT_
A
DDRESS, SYMBOL
LSB RESET
ADCH ADC CONVERTER RESULT
HIGH BYTE E2H ADC.9 ADC.8 ADC.7 ADC.6 ADC.5 ADC.4 ADC.3 ADC.2 xxxx xxxxB
ADCCON ADC CONTROL REGISTER E1H ADCEN - ADCEX ADCI ADCS AADR2 AADR1 AADR0 0x00 0000
B
ACC ACCUMULATOR E0H (E7) (E6) (E5) (E4) (E3) (E2) (E1) (E0) 0000 0000
B
PWMCON3 PWM CONTROL REGISTER
3 DFH PWM7B PWM6B PWM5B PWM4B PWM3B PWM2B PWM1B PWM0B 0000 0000
B
PWM6L PWM 6 LOW BITS
REGISTER DEH PWM6.7 PWM6.6 PWM6.5 PWM6.4 PWM6.3 PWM6.2 PWM6.1 PWM6.0 0000 0000
B
PWM2L PWM 2 LOW BITS
REGISTER DDH PWM2.7 PWM2.6 PWM2.5 PWM2.4 PWM2.3 PWM2.2 PWM2.1 PWM2.0 0000 0000
B
PWMCON1 PWM CONTROL REGISTER
1 DCH PWMRU
N Load PWMF
CLRPW
M PWM6I PWM4I PWM2I PWM0I 0000 0000
B
N
VMADDRL NVM LOW BYTE ADDRESS DBH NVMAD
DRH.7 NVMAD
DRH.6 NVMAD
DRH.5 NVMAD
DRH.4 NVMAD
DRH.3 NVMAD
DRH.2 NVMAD
DRH.1 NVMAD
DRH.8 0000 0000
B
PWM0L PWM 0 LOW BITS
REGISTER DAH PWM0.7 PWM0.6 PWM0.5 PWM0.4 PWM0.3 PWM0.2 PWM0.1 PWM0.0 0000 0000
B
PWMPL PWM COUNTER LOW
REGISTER D9H PWMP.7 PWMP.6 PWMP.5 PWMP.4 PWMP.3 PWMP.2 PWMP.1 PWMP.0 0000 0000
B
WDCON WATCH-DOG CONTROL D8H
(DF)
- (DE)
POR (DD)
- (DC)
- (DB)
WDIF (DA)
WTRF (D9)
EWT (D8)
RWT 0100 0000
B
WDCON2 WATCH-DOG CONTROL2 D7H - - - - - - - STRLD 0000 0000
B
PWM6H PWM 6 HIGH BITS
REGISTER D6H - - - - PWM6.1
1 PWM6.1
0 PWM6.9 PWM6.8 xxxx 0000B
PWM2H PWM 2 HIGH BITS
REGISTER D5H - - - - PWM2.1
1 PWM2.1
0 PWM2.9 PWM2.8 xxxx 0000B
QEICON QEI CONTROL REGISTER D4H - - - DISIDX DIR QEIM1 QEIM0 QEIEN xxx0 0000B
NVMDAT NVM DATA D3H NVMDA
T.7 NVMDA
T.6 NVMDA
T.5 NVMDA
T.4 NVMDA
T.3 NVMDA
T.2 NVMDA
T.1 NVMDA
T.0 0000 0000
B
PWM0H PWM 0 HIGH BITS
REGISTER D2H - - - - PWM0.1
1 PWM0.1
0 PWM0.9 PWM0.8 xxxx 0000B
PWMPH PWM COUNTER HIGH
REGISTER D1H - - - - PWMP.1
1 PWMP.1
0 PWMP.9 PWMP.8 xxxx 0000B
PSW PROGRAM STATUS WORD D0H
(D7)
CY (D6)
AC (D5)
F0 (D4)
RS1 (D3)
RS0 (D2)
OV (D1)
F1 (D0)
P 0000 0000
B
PWM4L PWM 4 LOW BITS
REGISTER CFH PWM4.7 PWM4.6 PWM4.5 PWM4.4 PWM4.3 PWM4.2 PWM4.1 PWM4.0 0000 0000
B
PWMCON2 PWM CONTROL REGISTER
2 CEH BKCH BKPS BPEN BKEN FP1 FP0 PMOD1 PMOD0 0000 0000
B
TH2 T2 REG. HIGH CDH TH2.7 TH2.6 TH2.5 TH2.4 TH2.3 TH2.2 TH2.1 TH2.0 0000 0000
B
TL2 T2 REG. LOW CCH TL2.7 TL2.6 TL2.5 TL2.4 TL2.3 TL2.2 TL2.1 TL2.0 0000 0000
B
RCAP2H T2 CAPTURE LOW CBH RCAP2H
.7 RCAP2H
.6 RCAP2H
.5 RCAP2H
.4 RCAP2H
.3 RCAP2H
.2 RCAP2H
.1 RCAP2H
.0 0000 0000
B
RCAP2L T2 CAPTURE HIGH CAH RCAP2L
.7 RCAP2L
.6 RCAP2L
.5 RCAP2L
.4 RCAP2L
.3 RCAP2L
.2 RCAP2L
.1 RCAP2L
.0 0000 0000
B
T2MOD TIMER 2 MODE C9H HC5 HC4 HC3 HC2 T2CR - - DCEN 0000 0xx0
B
T2CON TIMER 2 CONTROL C8H (CF)
TF2 (CE)
EXF2 (CD)
RCLK (CC)
TCLK (CB)
EXEN2 (CA)
TR2
(C9)
TC/
(C8)
RL2CP/ 0000 0000
B
TA TIME ACCESS REGISTER C7H TA.7 TA.6 TA.5 TA.4 TA.3 TA.2 TA.1 TA.0 0000 0000
B
DDIO DISABLE DIGITAL I/O C6H DDIO.7 DDIO.6 DDIO.5 DDIO.4 DDIO.3 DDIO.2 DDIO.1 DDIO.0 0000 0000
B
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 24 - Revision A4.0
Continued
SYMBOL DEFINITION ADDR
ESS
MSB BIT_
A
DDRESS, SYMBOL
LSB RESET
FSPLT FAULT SAMPLING TIME
REGISTER C5H SCMP1 SCMP0 SFP1 SFP0 SFCEN SFCST SFCDIR LSBD 0000 0000
B
PMR POWER MANAGEMENT
REGISTER C4H - - - - - ALEOFF - DME0 xxxx x0x0B
T3CON TIMER 3 CONTROL C3H TF3 - - - - TR3 - 0xxx x0x0B
T3MOD TIMER 3 MODE CONTROL C2H ENLD ICEN2 ICEN1 ICEN0 T3CR - - - 0000 0xxxB
SBUF1 SERIAL BUFFER 1 C1H SBUF1.7 SBUF1.6 SBUF1.5 SBUF1.4 SBUF1.3 SBUF1.2 SBUF1.1 SBUF1.0 xxxx xxxxB
SCON1 SERIAL CONTROL 1 C0H (BF)
SM0_1/F
E_1
(BE)
SM1_1 (BD)
SM2_1 (BC)
REN_1 (BB)
TB8_1 (BA)
RB8_1 (B9)
TI_1 (B8)
RI_1 0000 0000
B
PWM4H PWM 4 HIGH BITS
REGISTER BFH - - - - PWM4.11PWM4.1
0
PWM4.9 PWM4.8 xxxx 0000B
PWMEN PWM OUTPUT ENABLE
REGISTER BEH PWM7E
N PWM6E
N PWM5E
N PWM4E
N PWM3E
N PWM2E
N PWM1E
N PWM0E
N 0000 0000
B
PIO PWM PIN OUTPUT
SOURCE SELECT BDH PIO7 PIO6 PIO5 PIO4 PIO3 PIO2 PIO1 PIO0 0000 0000
B
POVD PWM OUTPUT STATE
REGISTERS BCH POVD.7 POVD.6 POVD.5 POVD.4 POVD.3 POVD.2 POVD.1 POVD.0 0000 0000
B
POVM PWM OUTPUT OVERRIDE
CONTROL REGISTERS BBH POVM.7 POVM.6 POVM.5 POVM.4 POVM.3 POVM.2 POVM.1 POVM.0 0000 0000
B
SADEN1 SLAVE ADDRESS MASK 1 BAH SADEN1
.7 SADEN1
.6 SADEN1
.5 SADEN1
.4 SADEN1
.3 SADEN1
.2 SADEN1
.1 SADEN1
.0 0000 0000
B
SADEN SLAVE ADDRESS MASK B9H SADEN.
7 SADEN.
6 SADEN.
5 SADEN.
4 SADEN.
3 SADEN.
2 SADEN.
1 SADEN.
0 0000 0000
B
IP INTERRUPT PRIORITY B8H
(BF)
(BE)
PADC (BD)
PT2 (BC)
PS (BB)
PT1 (BA)
PX1 (B9)
PT0 (B8)
PX0 0000 0000
B
IPH INTERRUPT HIGH
PRIORITY B7H - PADCH PT2H PSH PT1H PX1H PT0H PX0H x000 0000
B
EIP1H EXTENDED INTERRUPT
HIGH PRIORITY 1 B6H - - PNVMIH PCPTFH PT3H PBKFH PPWMH PSPIH xx00 0000
B
RCAP3H RELOAD CAPTURE 3 HIGH
REGISTER B5H RCAP3H
.7 RCAP3H
.6 RCAP3H
.5 RCAP3H
.4 RCAP3H
.3 RCAP3H
.2 RCAP3H
.1 RCAP3H
.0 0000 0000
B
RCAP3L RELOAD CAPTURE 3 LOW
REGISTER B4H RCAP3L
.7 RCAP3L
.6 RCAP3L
.5 RCAP3L
.4 RCAP3L
.3 RCAP3L
.2 RCAP3L
.1 RCAP3L
.0 0000 0000
B
P5 PORT 5 B1H - - - - - - PWM7 PWM6 xxxx xx11B
P3 PORT 3 B0H
(B7)
RD (B6)
WR
(B5)
T1/
IC1/QEB
(B4)
T0/
ICO/QE
A
(B3)
/INT1 (B2)
/INT0 (B1)
TXD (B0)
RXD 1111 1111
B
SFRCN F/W FLASH CONTROL AFH - WFWIN NOE NCE CTRL3 CTRL2 CTRL1 CTRL0 x011 1111
B
SFRFD F/W FLASH DATA AEH D7 D6 D5 D4 D3 D2 D1 D0 xxxx xxxxB
SFRAH F/W FLASH HIGH
ADDRESS ADH A15 A14 A13 A12 A11 A10 A9 A8 0000 0000
B
SFRAL F/W FLASH LOW ADDRESS ACH A7 A6 A5 A4 A3 A2 A1 A0 0000 0000
B
SADDR1 SLAVE ADDRESS 1 AAH SADDR1
.7 SADDR1
.6 SADDR1
.5 SADDR1
.4 SADDR1
.3 SADDR1
.2 SADDR1
.1 SADDR1
.0 0000 0000
B
SADDR SLAVE ADDRESS A9H
SADDR.
7 SADDR.
6 SADDR.
5 SADDR.
4 SADDR.
3 SADDR.
2 SADDR.
1 SADDR.
0 0000 0000
B
IE INTERRUPT ENABLE A8H
(AF)
EA (AE)
EADC (AD)
ET2 (AC)
ES (AB)
ET1 (AA)
EX1 (A9)
ET0 (A8)
EX0 0000 0000
B
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 25 - Revision A4.0
Continued
SYMBOL DEFINITION ADDR
ESS
MSB BIT_
A
DDRESS, SYMBOL
LSB RESET
CCH2/MAX
CNTH
INPUT CAPTURE 2 HIGH
REGISTER/ MAXIMUM
COUNTER HIGH REGISTER A7h CCH2.7
/MAXCN
TH.7
CCH2.6
MAXCN
TH.6
CCH2.5
/MAXCN
TH.5
CCH2.4
/MAXCN
TH.4
CCH2.3
/MAXCN
TH.3
CCH2.2
/MAXCN
TH.2
CCH2.1
/MAXCN
TH.1
CCH2.0
/MAXCN
TH.0 0000 0000
B
CCL2/MAX
CNTL
INPUT CAPTURE 2 LOW
REGISTER/ MAXIMUM
COUNTER LOW REGISTER A6h CCL2.7
/MAXCN
TL.7
CCL2.6
/MAXCN
TL.6
CCL2.5
/MAXCN
TL.5
CCL2.4
/MAXCN
TL.4
CCL2.3
/MAXCN
TL.3
CCL2.2
/MAXCN
TL.2
CCL2.1
/MAXCN
TL.1
CCL2.0
/MAXCN
TL.0 0000 0000
B
P4 PORT 4 A5H - - - - P4.3 P4.2 T2EX/IC
2
STADC xxxx 1111B
CAPCON1 CAPTURE CONTROL 1
REGISTER A4H - - ENF2 ENF1 ENF0 CPTF2
CPTF1/
DIRF CPTF0/
QEIF xx00 0000
B
CAPCON0 CAPTURE CONTROL 0
REGISTER A3H CCT2.1 CCT2.0 CCT1.1 CCT1.0 CCT0.1 CCT0.0 CCLD1 CCLD0 0000 0000
B
P4CSIN P4 CS SIGN A2H P43INV P42INV P41INV P40INV - PWDNH RMWFP P0UP 0000 x000
B
XRAMAH RAM HIGH BYTE
ADDRESS A1H - - - - - A10 A9 A8 0000 0000
B
P2 PORT 2 A0H
(A7)
A15/
SDA
(A6)
A14/
SCL
(A5)
A13/
PWM5
(A4)
A12/
PWM4
(A3)
A11/
PWM3
(A2)
A10/
PWM2
(A1)
A9/
PWM1
(A0)
A8/
PWM0 1111 1111
B
CHPCON ON CHIP PROGRAMMING
CONTROL 9FH SWRST/
REBOOT - LD/AP - - - LDSEL ENP 0000 0000
B
NVMCON NVM CONTROL 9EH EER EWR EnNVM - - - - NVMF 000x xxx0B
P43AH HI ADDR. COMPARATOR
OF P4.3 9DH A15 A14 A13 A12 A11 A10 A9 A8 0000 0000
B
P43AL LO ADDR. COMPARATOR
OF P4.3 9CH A7 A6 A5 A4 A3 A2 A1 A0 0000 0000
B
P42AH HI ADDR. COMPARATOR
OF P4.2 9BH A15 A14 A13 A12 A11 A10 A9 A8 0000 0000
B
P42AL LO ADDR. COMPARATOR
OF P4.2 9AH A7 A6 A5 A4 A3 A2 A1 A0 0000 0000
B
SBUF SERIAL BUFFER 99H SBUF.7 SBUF.6 SBUF.5 SBUF.4 SBUF.3 SBUF.2 SBUF.1 SBUF.0 xxxx xxxxB
SCON SERIAL CONTROL 98H
(9F)
SM0/FE (9E)
SM1 (9D)
SM2 (9C)
REN (9B)
TB8 (9A)
RB8 (99)
TI (98)
RI 0000 0000
B
P41AH HI ADDR. COMPARATOR
OF P4.1 97H A15 A14 A13 A12 A11 A10 A9 A8 0000 0000
B
P41AL LO ADDR. COMPARATOR
OF P4.1 96H A7 A6 A5 A4 A3 A2 A1 A0 0000 0000
B
P40AH HI ADDR. COMPARATOR
OF P4.0 95H A15 A14 A13 A12 A11 A10 A9 A8 0000 0000
B
P40AL LO ADDR. COMPARATOR
OF P4.0 94H A7 A6 A5 A4 A3 A2 A1 A0 0000 0000
B
P4CONB P4 CONTROL REGISTER B 93H P43FUN
1 P43FUN
0 P43CMP
1 P43CMP
0 P42FUN
1 P42FUN
0 P42CMP
1 P42CMP
0 0000 0000
B
P4CONA P4 CONTROL REGISTER A 92H P41FUN
1 P41FUN
0 P41CMP
1 P41CMP
0 P40FUN
1 P40FUN
0 P40CMP
1 P40CMP
0 0000 0000
B
EXIF EXTERNAL INTERRUPT
FLAG 91H IE5 IE4 IE3 IE2 - - - - 0000 xxxxB
P1 PORT 1 90H
(97)
ADC7 (96)
ADC6 (95)
ADC5 (94)
ADC4
(93)
TXD1/
ADC3
(92)
RXD1/
ADC2
(91)
ADC1/
Brake
(90)
T2/
ADC0 1111 1111
B
CKCON1 CLOCK CONTROL 1 8FH - - - - - - CCDIV1 CCDIV0 0000 0000
B
CKCON CLOCK CONTROL 8EH WD1 WD0 T2M T1M T0M MD2 MD1 MD0 0000 0001
B
TH1 TIMER HIGH 1 8DH TH1.7 TH1.6 TH1.5 TH1.4 TH1.3 TH1.2 TH1.1 TH1.0 0000 0000
B
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 26 - Revision A4.0
Continued
SYMBOL DEFINITION ADDR
ESS
MSB BIT_
A
DDRESS, SYMBOL
LSB RESET
TH0 TIMER HIGH 0 8CH TH0.7 TH0.6 TH0.5 TH0.4 TH0.3 TH0.2 TH0.1 TH0.0 0000 0000
B
TL1 TIMER LOW 1 8BH TL1.7 TL1.6 TL1.5 TL1.4 TL1.3 TL1.2 TL1.1 TL1.0 0000 0000
B
TL0 TIMER LOW 0 8AH TL0.7 TL0.6 TL0.5 TL0.4 TL0.3 TL0.2 TL0.1 TL0.0 0000 0000
B
TMOD TIMER MODE 89H GATE TC / M1 M0 GATE TC / M1 M0 0000 0000
B
TCON TIMER CONTROL 88H
(8F)
TF1 (8E)
TR1 (8D)
TF0 (8C)
TR0 (8B)
IE1 (8A)
IT1 (89)
IE0 (88)
IT0 0000 0000
B
PCON POWER CONTROL 87H SMOD SMOD0 - - GF1 GF0 PD IDL 00xx 0000
B
TH3 TIMER HIGH 3 85H TH3.7 TH3. 6 TH3.5 TH3.4 TH3.3 TH3.2 TH3.1 TH3.0 0000 0000
B
TL3 TIMER LOW 3 84H TL3.7 TL3.6 TL3.5 TL3.4 TL3.3 TL3.2 TL3.1 TL3.0 0000 0000
B
DPH DATA POINTER HIGH 83H DPH.7 DPH.6 DPH.5 DPH.4 DPH.3 DPH.2 DPH.1 DPH.0 0000 0000
B
DPL DATA POINTER LOW 82H DPL.7 DPL.6 DPL.5 DPL.4 DPL.3 DPL.2 DPL.1 DPL.0 0000 0000
B
SP STACK POINTER 81H SP.7 SP.6 SP.5 SP.4 SP.3 SP.2 SP.1 SP.0 0000 0111
B
P0 PORT 0 80H
(87)
INT5 (86)
INT4 (85)
INT3 (84)
INT2 (83)
/SS (82)
SPCLK (81)
MOSI (80)
MISO 1111 1111
B
Table 7-2: Special Function Registers
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 27 - Revision A4.0
PORT 0
Bit: 7 6 5 4 3 2 1 0
P0.7 P0.6 P0.5 P0.4 P0.3 P0.2 P0.1 P0.0
Mnemonic: P0 Address: 80h
Port 0 is an open-drain 8-bit bi-directional I/O port. As an alternate function Port 0 can function as the
multiplexed address/data bus to access off-chip memory. During the time when ALE is high, the LSB
of a memory address is presented. When ALE is low, the port transits to a bi-directional data bus. This
bus is used for reading external ROM and for reading or writing external RAM memory or peripherals.
When use d as a me mory bus , the p ort provid es active high drivers. The reset condition of Port 0 is tri-
state. Pull-up resistors are required when using Port 0 as an I/O port.
BIT NAME FUNCTION
0 P0.0 MISO: SPI Master In Slave Out.
1 P0.1 MOSI: SPI Master Out Slave In.
2 P0.2 SPCLK: SPI Clock.
3 P0.3 /SS: Slave Select.
4 P0.4 INT2: External Interrupt 2.
5 P0.5 INT3: External Interrupt 3.
6 P0.6 INT4: External Interrupt 4.
7 P0.7 INT5: External Interrupt 5.
STACK POINTER
Bit: 7 6 5 4 3 2 1 0
SP.7 SP.6 SP.5 SP.4 SP.3 SP.2 SP.1 SP.0
Mnemonic: SP Address: 81h
The Stack Pointer stores the Scratch-pad RAM address where the stack begins. In other words it
always points to the top of the stack.
DATA POINTER LOW
Bit: 7 6 5 4 3 2 1 0
DPL.7 DPL.6 DPL.5 DPL.4 DPL.3 DPL.2 DPL.1 DPL.0
Mnemonic: DPL Address: 82h
This is the low byte of the standard 8032 16-bit data pointer.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 28 - Revision A4.0
DATA POINTER HIGH
Bit: 7 6 5 4 3 2 1 0
DPH.7 DPH.6 DPH.5 DPH.4 DPH.3 DPH.2 DPH.1 DPH.0
Mnemonic: DPH Address: 83h
This is the high byte of the standard 8032 16-bit data pointer.
TIMER 3 LSB
Bit: 7 6 5 4 3 2 1 0
TL3.7 TL3.6 TL3.5 TL3.4 TL3.3 TL3.2 TL3.1 TL3.0
Mnemonic: TL3 Address: 84h
BIT NAME FUNCTION
7-0 Timer 3 LSB LSB of Timer3
TIMER 3 MSB
Bit: 7 6 5 4 3 2 1 0
TH3.7 TH3.6 TH3.5 TH3.4 TH3.3 TH3.2 TH3.1 TH3.0
Mnemonic: TH3 Address: 85h
BIT NAME FUNCTION
7-0 Timer 3 MSB MSB of Timer3
POWER CONTROL
Bit: 7 6 5 4 3 2 1 0
SMOD SMOD0 - - GF1 GF0 PD IDL
Mnemonic: PCON Address: 87h
BIT NAME FUNCTION
7 SMOD This bit doubles the serial port baud rate in mode 1, 2, and 3 when set to 1.
6 SMOD0 Framing Error Detection Enable. When SMOD0 is set to 1, then SCON.7
(SCON1.7) now indicates a Frame Error and acts as the FE (FE_1) flag. When
SMOD0 is 0, then SCON.7 (SCON1.7) a cts a s pe r the standard 8032 function.
5-4 - Reserved.
3-2 GF1-0 These two bits are general purpose user flags.
1 PD Setting this bit causes the device to go into the POWERDOWN mode. In this
mode all the clocks are stopped and program exe cution is frozen.
0 IDL
Setting this bit causes the device to go into the IDLE mode. In this mode the
clock to the CPU is stopped, so program execution is frozen, but the clock to the
serial ports, timer, PWM, ADC, SPI and interrupt blocks is not stopped, and
these blocks continue operating unhi ndered.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 29 - Revision A4.0
TIMER CONTROL
Bit: 7 6 5 4 3 2 1 0
TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0
Mnemonic: TCON Address: 88h
BIT NAME FUNCTION
7 TF1 Timer 1 Overflow Flag. This bit is set when Timer 1 overflows. It is cleared
automatically when the program does a timer 1 interrupt service routine.
Software can also set or clear this bit.
6 TR1 Timer 1 Run Control. This bit is set or cleared by software to turn timer/counter
on or off.
5 TF0 Timer 0 Overflow Flag. This bit is set when Timer 0 overflows. It is cleared
automatically when the program does a timer 0 interrupt service routine.
Software can also set or clear this bit.
4 TR0 Timer 0 Run Control. This bit is set or cleared by software to turn timer/counter
on or off.
3 IE1
Interrupt 1 Edge Detect Flag: Set by hardware when an edge/level is detected
on INT1. This bit is cleared by hardware when the service routine is vectored to
only if the interrupt was edge triggered. Otherwise it follows the inverse of the
pin.
2 IT1 Interrupt 1 Type Control. Set/cleared by software to specify falling edge/ low
level triggered external inputs.
1 IE0
Interrupt 0 Edge Detect Flag. Set by hardware when an edge/level is detected
on INT0. This bit is cleared by hardware when the service routine is vectored to
only if the interrupt was edge triggered. Otherwise it follows the inverse of the
pin.
0 IT0 Interrupt 0 Type Control: Set/cleared by software to specify falling edge/ low
level triggered external inputs.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 30 - Revision A4.0
TIMER MODE CONTROL
Bit: 7 6 5 4 3 2 1 0
GATE
TC/ M1 M0 GATE TC/ M1 M0
TIMER1 TIMER0
Mnemonic: TMOD Address: 89h
BIT NAME FUNCTION
7 GATE
Gating control: When this bit is set, Timer 1 is enabled only while the INT1 pin is high
and the TR1 control bit is set. When cleared, the INT1 pin has no effect, and Timer 1
is enabled whenever TR1 is set.
6 TC/ Timer or Counter Select: When clear, Timer 1 is incremented by the internal clock.
When set, the timer counts falling ed ges on the T1 pin.
5 M1 Timer 1 mode sele ct bit 1. See table below.
4 M0 Timer 1 mode sele ct bit 0. See table below.
3 GATE
Gating control: When this bit is set, Timer 0 is enabled only while the INT0 pin is
high and the TR0 control bit is set. When cleared, the INT0 pin has no effect, and
Timer 0 is enabled whenever TR0 is set.
2 TC/ Timer or Counter Select: When clear, Timer 0 is incremented by the internal clock.
When set, the timer counts falling ed ges on the T0 pin.
1 M1 Timer 0 mode sele ct bit 1. See table below.
0 M0 Timer 0 mode sele ct bit 0. See table below.
M1, M0: Mode Select bits:
M1 M0 Mode
0 0 Mode 0: 8-bit timer/counter TLx serves as 5-bit pre-scale.
0 1 Mode 1: 16-bit timer/counter, no pre-scale.
1 0 Mode 2: 8-bit timer/counter with auto-reload from THx
1 1 Mode 3:
(Timer 0) TL0 is an 8-bit timer/counter controlled by the standard Timer-0 control
bits. TH0 is an 8-bit timer only controlled by Timer-1 control bits.
(Timer 1) Timer/Counter 1 is stopped.
TIMER 0 LSB
Bit: 7 6 5 4 3 2 1 0
TL0.7 TL0.6 TL0.5 TL0.4 TL0.3 TL0.2 TL0.1 TL0.0
Mnemonic: TL0 Address: 8Ah
TL0.7-0 Timer 0 LSB
TIMER 1 LSB
Bit: 7 6 5 4 3 2 1 0
TL1.7 TL1.6 TL1.5 TL1.4 TL1.3 TL1.2 TL1.1 TL1.0
Mnemonic: TL1 Address: 8Bh
TL1.7-0 Timer 1 LSB
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 31 - Revision A4.0
TIMER 0 MSB
Bit: 7 6 5 4 3 2 1 0
TH0.7 TH0.6 TH0.5 TH0.4 TH0.3 TH0.2 TH0.1 TH0.0
Mnemonic: TH0 Address: 8Ch
TH0.7-0 Timer 0 MSB
TIMER 1 MSB
Bit: 7 6 5 4 3 2 1 0
TH1.7 TH1.6 TH1.5 TH1.4 TH1.3 TH1.2 TH1.1 TH1.0
Mnemonic: TH1 Address: 8Dh
TH1.7-0 Timer 1 MSB
CLOCK CONTROL
Bit: 7 6 5 4 3 2 1 0
WD1 WD0 T2M T1M T0M MD2 MD1 MD0
Mnemonic: CKCON Address: 8Eh
BIT NAME FUNCTION
7 WD1
Watchdog Timer mode select bit 1. See table below.
6 WD0
Watchdog Timer mode select bit 0. See table below.
5 T2M
Timer 2 clock select:
1: divide-by-4 clock.
0: divide-by-12 clock.
4 T1M
Timer 1 clock select:
1: divide-by-4 clock.
0: divide-by-12 clock.
3 T0M
Timer 0 clock select:
1: divide-by-4 clock.
0: divide-by-12 clock.
2 MD2
Stretch MOVX select bit 2:
MD2, MD1, and MD0 select the stretch value for the MOVX instruction. The RD or
WR strobe is stretched by the selected interval, which enables the device to access
faster or slower external memory devices or peripherals without the need for
external circuits. By default, the stretch value is one. See table below.
(Note: When accessing on-chip SRAM, these bits have no effect, and the MOVX
instruction alway s t akes two machine cycles.)
1 MD1
Stretch MOVX select bit 1. See MD2.
0 MD0
Stretch MOVX select bit 0. See MD2.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 32 - Revision A4.0
WD1, WD0: Mode Select bits:
These bits determine the time-out periods for the Watchdog Timer. The reset time-out period is 512
clocks more than the interrupt time-out period.
WD1 WD0 INTERRUPT TIME-OUT RESET TIME-OUT
0 0 217 217 + 512
0 1 220 220 + 512
1 0 223 223 + 512
1 1 226 226 + 512
MD2, MD1, MD0: Stretch MOVX select bits:
MD2 MD1 MD0 STRETCH VALUE MOVX DURATION
0 0 0 0 2 machine cycles
0 0 1 1 3 machine cycles (Default)
0 1 0 2 4 machine cycles
0 1 1 3 5 machine cycles
1 0 0 4 6 machine cycles
1 0 1 5 7 machine cycles
1 1 0 6 8 machine cycles
1 1 1 7 9 machine cycles
CLOCK CONTROL 1
Bit: 7 6 5 4 3 2 1 0
- - - - - - CCDIV1 CCDIV0
Mnemonic: CKCON1 Address: 8Fh
BIT NAME FUNCTION
7-2 - Reserved.
1-0 CCDIV
Timer 3 clock select.
CCDIV1 CCDIV0 Timer 3 clock
0 0 Fosc
0 1 Fosc/4
1 0 Fosc/16
1 1 Fosc/32
PORT 1
Bit: 7 6 5 4 3 2 1 0
P1.7 P1.6 P1.5 P1.4 P1.3 P1.2 P1.1 P1.0
Mnemonic: P1 Address: 90h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 33 - Revision A4.0
BIT NAME FUNCTION
7-0 P1
General purpose I/O port. Most instructions will read the port pins in case of a
port read access, however in case of read-modify-write instructions, the port
latch is read. Some pins also have alternate input or output functions. The
alternate functions are described below.
ALTERNATE FUNCTION1 ALTERNATE FUNCTION2
P1.0 T2: External I/O for Timer/ Counter 2 ADC0: Analog input0
P1.1 PWM Brake ADC1: Analog input1
P1.2 RXD1 ADC2: Analog input2
P1.3 TXD1 ADC3: Analog input3
P1.4 ADC4: Analog input4
P1.5 ADC5: Analog input5
P1.6 ADC6: Analog input6
P1.7 ADC7: Analog input7
EXTERNAL INTERRUPT FLAG
Bit: 7 6 5 4 3 2 1 0
IE5 IE4 IE3 IE2 - - - -
Mnemonic: EXIF Address: 91h
BIT NAME FUNCTION
7 IE5 External Interrupt 5 flag. Set by hardware when a rising/falling/both edges is
detected onINT5 pin.
6 IE4 External Interrupt 4 flag. Set by hardware when a rising/falling/both edges is
detected on INT4 pin.
5 IE3 External Interrupt 3 flag. Set by hardware when a rising/falling/both edges is
detected on INT3 pin.
4 IE2 External Interrupt 2 flag. Set by hardware when a rising edge is detected on
INT2 pin.
3-0 - Reserved.
PORT 4 CONTROL REGISTER A
Bit: 7 6 5 4 3 2 1 0
P41FUN1 P41FUN0 P41CMP1 P41CMP0 P40FUN1 P40FUN0 P40CMP1 P40CMP0
Mnemonic: P4CONA Address: 92h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 34 - Revision A4.0
PORT 4 CONTROL REGISTER B
Bit: 7 6 5 4 3 2 1 0
P43FUN1 P43FUN0 P43CMP1 P43CMP0 P42FUN1 P42FUN0 P42CMP1 P42CMP0
Mnemonic: P4CONB Address: 93h
BIT NAME FUNCTION
P4xFUN1, P4xFUN0
Port 4 alternate modes.
=00: Mode 0. P4.x is a general purpose I/O port which is the same as Port 1.
=01: Mode 1. P4.x is a Read Strobe signal for chip select purpose. The
address range depends on the SFR P4xAH, P4xAL and bits P4xCMP1,
P4xCMP0.
=10: Mode 2. P4.x is a Write Strobe signal for chip select purpose. The
address range depends on the SFR P4xAH, P4xAL and bits P4xCMP1,
P4xCMP0.
=11: Mode 3. P4.x is a Read/Write Strobe signal for chip select purpose. The
address range depends on the SFR P4xAH, P4xAL and bits P4xCMP1,
P4xCMP0.
P4xCMP1, P4xCMP0
Port 4 Chip-select Mode addres s comparison:
=00: Compare the full address (16 bits length) with the base address registers
P4xAH and P4xAL.
=01: Compare the 15 high bits (A15-A1) of address bus with the base address
registers P4xAH and P4xAL.
=10: Compare the 14 high bits (A15-A2) of address bus with the base address
registers P4xAH and P4xAL.
=11: Compare the 8 high bits (A15-A8) of address bus with the base address
registers P4xAH and P4xAL.
P4.0 BASE ADDRESS LOW BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A7 A6 A5 A4 A3 A2 A1 A0
Mnemonic: P40AL Address: 94h
P4.0 BASE ADDRESS HIGH BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A15 A14 A13 A12 A11 A10 A9 A8
Mnemonic: P40AH Address: 95h
P4.1 BASE ADDRESS LOW BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A7 A6 A5 A4 A3 A2 A1 A0
Mnemonic: P41AL Address: 96h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 35 - Revision A4.0
P4.1 BASE ADDRESS HIGH BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A15 A14 A13 A12 A11 A10 A9 A8
Mnemonic: P41AH Address: 97h
SERIAL PORT CONTROL
Bit: 7 6 5 4 3 2 1 0
SM0/FE SM1 SM2 REN TB8 RB8 TI RI
Mnemonic: SCON Address: 98h
BIT NAME FUNCTION
7 SM0/FE
Serial Port mode select bit 0 or Framing Error Flag: This bit is controlled by the
SMOD0 bit in the PCON register.
(SM0) See table below.
(FE) This bit indicates an invalid stop bit. It must be manually cleared by software.
6 SM1 Serial Port mode select bit 1. See table below.
5 SM2
Serial Port Clock or Multi-Processor Communication.
(Mode 0) This bit controls the serial port clock. If set to zero, the serial port runs at a
divide-by-12 clock of the oscillator. This is compatible with the standard 8051/52. If
set to one, the serial clock is a divide-by-4 clock of the oscillator.
(Mode 1) If SM2 is set to one, RI is not activated if a valid stop bit is not received.
(Modes 2 / 3) This bit enables multi-processor communication. If SM2 is set to one,
RI is not activated if RB8, the ninth data bit, is zero.
4 REN
Receive enable:
1: Enable serial reception.
0: Disable serial reception.
3 TB8 (Modes 2 / 3) This is the 9th bit to transmit. This bit is set by software.
2 RB8
(Mode 0) No function.
(Mode 1) If SM2 = 0, RB8 is the stop bit that was received.
(Modes 2 / 3) This is the 9th bit that was received.
1 TI
Transmit interrupt flag: This flag is set by the hardware at the end of the 8th bit in
mode 0 or at the beginning of the stop bit in the other modes during serial
transmission. This bit must be cleared by software.
0 RI
Receive interrupt flag: This flag is set by the hardware at the end of the 8th bit in
mode 0 or halfway through the stop bits in the other modes during serial reception.
However, SM2 can restrict this behavior. This bit can only be cleared by software.
SM1, SM0: Mode Select bits:
SM0 SM1 MODE DESCRIPTION LENGTH BAUD RATE
0 0 0 Synchronous 8
Tclk divided by 4 or 12
0 1 1 Asynchronous 10
Variable
1 0 2 Asynchronous 11
Tclk divided by 32 or 64
1 1 3 Asynchronous 11
Variable
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 36 - Revision A4.0
ERIAL DATA BUFFER
Bit: 7 6 5 4 3 2 1 0
SBUF.7 SBUF.6 SBUF.5 SBUF.4 SBUF.3 SBUF.2 SBUF.1 SBUF.0
Mnemonic: SBUF Address: 99h
BIT NAME FUNCTION
7-0 SBUF
Serial data is read from or written to this location. It consis ts of two separate 8 bit
registers. One is the receive buffer, and the other is the transmit buffer. Any read
access gets data from the receive data buffer, while write access is to the
transmit data buffer.
P4.2 BASE ADDRESS LOW BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A7 A6 A5 A4 A3 A2 A1 A0
Mnemonic: P42AL Address: 9Ah
P4.2 BASE ADDRESS HIGH BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A15 A14 A13 A12 A11 A10 A9 A8
Mnemonic: P42AH Address: 9Bh
P4.3 BASE ADDRESS LOW BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A7 A6 A5 A4 A3 A2 A1 A0
Mnemonic: P43AL Address: 9Ch
P4.3 BASE ADDRESS HIGH BYTE REGISTER
Bit: 7 6 5 4 3 2 1 0
A15 A14 A13 A12 A11 A10 A9 A8
Mnemonic: P43AH Address: 9Dh
NVM CONTROL
Bit: 7 6 5 4 3 2 1 0
EER EWR EnNVM - - - - NVMF
Mnemonic: NVMCON Address: 9Eh
BIT NAME FUNCTION
7 EER
Set this bit to erase NVM data of page (n) to FFH.
The NVM has 32 pages that each page has 64 bytes data memory. By select
NVMADDRH and NVMADDRL of NVM address registers that will automatic
enable page area. If set this bit, the page will be page erased, after finished,
the NVMF flag will be set to “1”, then this bit will be cleared. If NVMF flag is set,
the erase and write NVM data memory are invalid.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 37 - Revision A4.0
Continued
BIT NAME FUNCTION
6 EWR
Set this bit is write data to NVM data memory by NVMADDRH and
NVMADDRL to decode NVM data memory. If finished, NVMF flag will be set to
“1”, and then this bit will be cleared. If NVMF flag is set, the erase and write
NVM are invalid.
5 EnNVM
To enable read NVM data memory a rea , refer as below table.
0: To disable the MOVX instruction to read NVM data memory.
1: To enable the MOVX instruction to read NVM data memory, the External
RAM or AUX-RAM will be disabled.
4~1 - Reserved.
0 NVMF
NVM data memory erases or writes finished flag.
If NVM data memory is finished by erase or write, it will be set to “1” by
hardware and clear by software. And it will be interrupted when NVM
erase/write interrupt is enabled.
ISP CONTROL REGISTER
Bit: 7 6 5 4 3 2 1 0
SWRST/
HWB - LD/AP - - - LDSEL ENP
Mnemonic: CHPCON Address: 9Fh
BIT NAME FUNCTION
7 W:SWRST
R:HWB
Write access to this bit is different from read access.
Write this bit to 1 to force the microcontroller to reset to the initial condition,
just like power-on reset. This action re-boots the microcontroller and starts
normal operation. This bit will be cleared during the reset.
Read this bit to determine whether or not a hardware reboot is in progress. If
CPU is rebooted by P3.6 & P3.7 or P4.3, this bit is set to 1 after the hardware
reboot.
Note: P4.3 pin is available in 48L LQFP package only .
6 - Reserved.
5 LD/AP
(read-only) 0: CPU is executing AP Flash EPROM
1: CPU is executing LD Flash EPROM
4-2 - Reserved.
1 LDSEL
(write-only)
Loader Program Location Selection. This bit should be set before entering ISP
mode.
0: The executing program is in the 64-KB AP Flash EPROM. The 4-KB LD
Flash EPROM is the destination for re-programming .
1: The executing program is in the 4-KB memory bank. The 64-KB AP Flash
EPROM is the destination for re-progra mming.
0 ENP
FLASH EPROM Programming Enable.
1: Enable in-system programming mode. In this mode, erase, program and
read operations are achieved.
0: Disable in-system programming mode. The on-chip flash memory is read-
only.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 38 - Revision A4.0
The way to enter ISP mode is to set ENP to 1 and write LDSEL properly then force CPU in IDLE
mode, after IDLE mode is released CPU will restart from AP or LD ROM according the value of
LDSEL.
PORT 2
Bit: 7 6 5 4 3 2 1 0
P2.7 P2.6 P2.5 P2.4 P2.3 P2.2 P2.1 P2.0
Mnemonic: P2 Address: A0h
BIT NAME FUNCTION
7-0 P2
This port functions as an address bus during external memory access, and as a
general-purpose I/O port on devices that incorporate internal program memory.
When P2 functions a non-multiplexed address bus A15-A8 the port latch cannot
be used for general I/O purposes but exists to support the MOVX instructions.
Port 2 data will only be brought out on the P2.7-0 pins during indirect MOVX
instructions.
ALTERNATE FUNCTION
P2.0 PWM0 output.
P2.1 PWM1 output.
P2.2 PWM2 output.
P2.3 PWM3 output.
P2.4 PWM4 output.
P2.5 PWM5 output.
P2.6 SCL, I2C serial clock.
P2.7 SDA, I2C serial data.
XRAMAH
Bit: 7 6 5 4 3 2 1 0
- - - - - A10 A9 A8
Mnemonic: XRAMAH Address: A1h
BIT NAME FUNCTION
7-3 - Reserved.
2-0 A10-8
XRAMAH is used for high byte address memory access through A15-8, when
CPU executes MOVX with R0 (or R1) instructions. Depending EnNVM and
DME0 setting, and address, the memory accessed may differs. Table below
shows the memory access destination.
This device has on-chip sram at 1/2/2K bytes.
Note: User should take care when accessing the memory with this instruction. Access to invalid
regions may cause undesirable results.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 39 - Revision A4.0
PORT 4 CHIP-SELECT POLARITY
Bit: 7 6 5 4 3 2 1 0
P43INV P42INV P41INV P40INV - PWDNH RMWFP PUP0
Mnemonic: P4CSIN Address: A2h
BIT NAME FUNCTION
7-4 P4xINV The Active Polarity of P4.x when it is set as a chip-select strobe output. High =
Active High. Low = Active Low. Note: x = 3,2,1,0.
3 - Reserved.
2 PWDNH
Set PWDNH to logic 1 then ALE and PSEN will keep high state, clear this bit to
logic 0 then ALE and PSEN will output low during power down mode.
1 RMWFP
Control Read Path of Instruction “Read-Modify-Write”. When this bit is set, the
read path of executing “read-modify-write” instruction is from port pin otherwise
from SFR.
0 PUP0 Enable Port 0 weak pull up.
CAPTURE CONTROL 0 REGISTER
Bit: 7 6 5 4 3 2 1 0
CCT2.1 CCT2.0 CCT1.1 CCT1.0 CCT0.1 CCT0.0 CCLD1 CCLD0
Mnemonic: CAPCON0 Address: A3h
BIT NAME FUNCTION
7-6 CCT2.1-0
Capture 2 edge select.
CCT2.1 CCT2.0 Description
0 0 Rising edge trigger
0 1 Falling edge trigger
1 0 Rising and falling edge trigger
1 1 Reserved.
5-4 CCT1.1-0
Capture 1 edge select.
CCT1.1 CCT1.0 Description
0 0 Rising edge trigger
0 1 Falling edge trigger
1 0 Rising and falling edge trigger
1 1 Reserved.
3-2 CCT0.1-0
Capture 0 edge select.
CCT0.1 CCT0.0 Description
0 0 Rising edge trigger
0 1 Falling edge trigger
1 0 Rising and falling edge trigger
1 1 Reserved.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 40 - Revision A4.0
Continued
BIT NAME FUNCTION
1-0 CCLD.1-0
Reload trigger select.
CCLD1 CCLD0 Description
0 0 Timer 3 overflow (default)
0 1 Reload by capture 0 block
1 0 Reload by capture 1 block
1 1 Reload by capture 2 block
CAPTURE CONTROL 1 REGISTER
Bit: 7 6 5 4 3 2 1 0
- - ENF2 ENF1 ENF0 CPTF2 CPTF1/ CPTF0
Mnemonic: CAPCON1 Address: A4h
BIT NAME FUNCTION
7-6 - Reserved.
5 ENF2 Enable filter for capture input 2.
4 ENF1 Enable filter for capture input 1.
3 ENF0 Enable filter for capture input 0.
2 CPTF2 Input capture/reload 2 interrupt flag.
1 CPTF1/DIRF
Input Capture 2 flag share the same bit with DIRF flag.
IC mode - Input capture/reload 1 interrupt flag.
QEI mode - Direction changed interrupt flag. Bit is set by hardware when
direction index (DIR) changes state and direction change interrupt is
requested if it is enabled. DIRF is cleare d by software.
0 CPTF0/QEIF
Input Capture 0 flag share the same bit with QEI flag.
IC mode – Input capture/reload 0 interrupt flag.
QEI mode - QEI interrupt flag.
1. In free-counting mode, if Pulse Counter overflow s or underflows.
2. In compare-counting mode, if Pulse Counter ove rflows from Maximum
Count to zero or underflows from zero to Maximum Count.
PORT 4
Bit: 7 6 5 4 3 2 1 0
- - - - P4.3 P4.2 P4.1 P4.0
Mnemonic: P4 Address: A5h
BIT NAME FUNCTION
7-4 - Reserved.
3-2 P4 GPIO.
1 P4 GPIO. Alternate function T2EX/IC2 for Timer 2 external trigger/Input Capture 2
respectively.
0 P4 GPIO. Alternate function STADC. External start ADC trigger input.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 41 - Revision A4.0
INPUT CAPTURE 2/MAXIMUM COUNTER LOW REGISTER
Bit: 7 6 5 4 3 2 1 0
CCL2.7/
MAXCNT
L.7
CCL2.6/
MAXCNT
L.6
CCL2.5/
MAXCNT
L.5
CCL2.4/
MAXCNT
L.4
CCL2.3/
MAXCNT
L.3
CCL2.2/
MAXCNT
L.2
CCL2.1/
MAXCNT
L.1
CCL2.0/
MAXCNT
L.0
Mnemonic: CCL2/MAXCNTL Address: A6h
INPUT CAPTURE 2/MAXIMUM COUNTER HIGH REGISTER
Bit: 7 6 5 4 3 2 1 0
CCH2.7/
MAXCNT
H.7
CCH2.6/
MAXCNT
H.6
CCH2.5/
MAXCNT
H.5
CCH2.4/
MAXCNT
H.4
CCH2.3/
MAXCNT
H.3
CCH2.2/
MAXCNT
H.2
CCH2.1/
MAXCNT
H.1
CCH2.0/
MAXCNT
H.0
Mnemonic: CCH2/MAXCNTH Address: A7h
INTERRUPT ENABLE
Bit: 7 6 5 4 3 2 1 0
EA EADC ET2 ES ET1 EX1 ET0 EX0
Mnemonic: IE Address: A8h
BIT NAME FUNCTION
7 EA Global enable: Enable/disable all interrupts.
6 EADC Enable ADC interrupt.
5 ET2 Enable Timer 2 interrupt.
4 ES Enable Serial Port 0 interrupts.
3 ET1 Enable Timer 1 interrupt.
2 EX1 Enable external interrupt 1.
1 ET0 Enable Timer 0 interrupt.
0 EX0 Enable external interrupt 0.
SLAVE ADDRESS
Bit: 7 6 5 4 3 2 1 0
SADDR.7 SADDR.6 SADDR.5 SADDR.4 SADDR.3 SADDR.2 SADDR.1 SADDR.0
Mnemonic: SADDR Address: A9h
BIT NAME FUNCTION
7-0 SADDR The SADDR should be programmed to the given or broadcast address for serial
port to which the slave processor is desi gnated.
SLAVE ADDRESS 1
Bit: 7 6 5 4 3 2 1 0
SADDR1.7 SADDR1.6 SADDR1.5 SADDR1.4 SADDR1.3 SADDR1.2 SADDR1.1 SADDR1.0
Mnemonic: SADDR1 Address: AAh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 42 - Revision A4.0
BIT NAME FUNCTION
7-0 SADDR1 The SADDR1 should be programmed to the given or broadcast address for
serial port 1 to which the slave processor is designate d.
ISP ADDRESS LOW BYTE
Bit: 7 6 5 4 3 2 1 0
A7 A6 A5 A4 A3 A2 A1 A0
Mnemonic: SFRAL Address: ACh
Low byte destination address for In System Prog ramming operations.
ISP ADDRESS HIGH BYTE
Bit: 7 6 5 4 3 2 1 0
A15 A14 A13 A12 A11 A10 A9 A8
Mnemonic: SFRAH Address: ADh
Low byte destination address for In System Programming operations. (SFRAH, SFRAL) represents
the address of the ROM byte that will be erased, programmed or read.
ISP DATA BUFFER
Bit: 7 6 5 4 3 2 1 0
D7 D6 D5 D4 D3 D2 D1 D0
Mnemonic: SFRFD Address: AEh
In ISP mode, read/write a specific byte ROM content must go through SFRF D register.
ISP OPERATION MODES
Bit: 7 6 5 4 3 2 1 0
- WFWIN NOE NCE CTRL3 CTRL2 CTRL1 CTRL0
Mnemonic: SFRCN Address: AFh
BIT NAME FUNCTION
7 - Reserved.
6 WFWIN On-chip FLASH EPROM bank select for in-system programming .
0= AP FLASH EPROM bank is selected as destination for re-programming.
1= LD FLASH EPROM bank is selected as destination for re-programming.
5 NOE Flash EPROM output enable.
4 NCE Flash EPROM chip enable.
3-0 CTRL The Flash Control Signals.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 43 - Revision A4.0
ISP MODE WFWIN NOE NCE CTRL[3:0] SFRAH,
SFRAL SFRFD
Erase 4KB LD Flash 1 1 0 0010 X X
Erase 16/32/64K AP
Flash 0 1 0 0010 X X
Program 4KB LD Flash 1 1 0 0001 Address in Data in
Program 16/32/64KB
AP Flash 0 1 0 0001 Address in Data in
Read 4KB LD Flash 1 0 0 0000 Address in Data out
Read 16/32/64KB AP
Flash 0 0 0 0000 Address in Data out
PORT 3
Bit: 7 6 5 4 3 2 1 0
P3.7 P3.6 P3.5 P3.4 P3.3 P3.2 P3.1 P3.0
Mnemonic: P3 Address: B0h
BIT NAME FUNCTION
7-0 P3 General purpose I/O port. Each pin also has an alternate input or output function
that is controlled by other SFRs. The alternate function is enabled if the
corresponding port latch bit is set to 1.
ALTERNATE FUNCTION
P3.7 RD Strobe for read from external RAM.
P3.6 WR Strobe for write to external RAM.
P3.5 T1/IC1/QEB; Timer/counter 1 external count input/Input Capture 1/QEI input B.
P3.4 T0/IC0/QEA; Timer/counter 0 external count input/Input Capture 0/QEI input A.
P3.3 /INT0 External interrupt 1.
P3.2 /INT1 External interrupt 0.
P3.1 TxD Serial port output.
P3.0 RxD Serial port input.
PORT 5
Bit: 7 6 5 4 3 2 1 0
- - - - - - P5.1 P5.0
Mnemonic: P5 Address: B1h
BIT NAME FUNCTION
7-2 - Reserved.
1-0 P5 General purpose I/O port. Each pin also has an alternate input or output
function. This port can not support bit ad dressable.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 44 - Revision A4.0
ALTERNATE FUNCTION
P5.1 PWM7 output function
P5.0 PWM6 output function
TIMER 3 RELOAD LSB
Bit: 7 6 5 4 3 2 1 0
RCAP3L.7 RCAP3L.6 RCAP3L.5 RCAP3L.4 RCAP3L.3 RCAP3L.2 RCAP3L.1 RCAP3L.0
Mnemonic: RCAP3L Address: B4h
BIT NAME FUNCTION
7-0 RCAP3L Timer 3 Reload LSB: This register is LSB of a 16 bit reload value when timer 3 is
configured in reload mode. It served also as a compare register when timer 3 is
configured as compare mode (see CMP/RL3 bit).
TIMER 3 RELOAD MSB
Bit: 7 6 5 4 3 2 1 0
RCAP3H.7 RCAP3H.6 RCAP3H.5 RCAP3H.4 RCAP3H.3 RCAP3H.2 RCAP3H.1 RCAP3H.0
Mnemonic: RCAP3H Address: B5h
BIT NAME FUNCTION
7-0 RCAP3H Timer 3 Reload MSB: This register is MSB of a 16 bit reload value when timer 3
is configured in reload mode. It served also as a compare register when timer 3
is configured as compare mode (se e CMP/RL3 bit).
EXTENDED INTERRUPT HIGH PRIORITY 1
Bit: 7 6 5 4 3 2 1 0
- - PNVMIH PCPTFH PT3H PBKFH PPWMFH PSPIH
Mnemonic: EIP1 Address: B6h
BIT NAME FUNCTION
7-6 - Reserved.
5 PNVMIH NVM interrupt High priority. PNVMIH = 1 sets it to highest priority level.
4 PCPTFH
Capture/reload Interrupt High priority. PCPTFH = 1 sets it to highest priority
level.
3 PT3H Timer 3 Interrupt High priority. PT3H = 1 sets it to highest priority level.
2 PBKFH PWM Brake Interrupt High priority. PBKFH = 1 sets it to highest priority level.
1 PPWMFH PWM period Interrupt High priority. PPWMFH = 1 sets it to highest priority level.
0 PSPIH SPI Interrupt High Priority. PSPIH = 1 sets it to highest priority level.
INTERRUPT HIGH PRIORITY
Bit: 7 6 5 4 3 2 1 0
- PADCH PT2H PSHH PT1H PX1H PT0H PX0H
Mnemonic: IPH Address: B7h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 45 - Revision A4.0
BIT NAME FUNCTION
7 - Reserved.
6 PADCH This bit defines the ADC interrupt High priority. PADCH = 1 sets it to highest
priority level.
5 PT2H This bit defines the Timer 2 interrupt High priority. PT2H = 1 sets it to highest
priority level.
4 PSH This bit defines the Serial port 0 interrupt High priority. PSH = 1 sets it to highest
priority level.
3 PT1H This bit defines the Timer 1 interrupt High priority. PT1H = 1 sets it to highest
priority level.
2 PX1H This bit defines the External interrupt 1 High priority. PX1H = 1 sets it to highest
priority level.
1 PT0H This bit defines the Timer 0 interrupt High priority. PT0H = 1 sets it to highest
priority level.
0 PX0H This bit defines the External interrupt 0 High priority. PX0H = 1 sets it to highest
priority level.
INTERRUPT PRIORITY
Bit: 7 6 5 4 3 2 1 0
- PADC PT2 PS PT1 PX1 PT0 PX0
Mnemonic: IP Address: B8h
BIT NAME FUNCTION
7 - Reserved.
6 PADC This bit defines the ADC interrupt priority. PADC = 1 sets it to higher priority level.
5 PT2 This bit defines the Timer 2 interrupt priority. PT2 = 1 sets it to higher priority
level.
4 PS This bit defines the Serial port 0 interrupt priority. PS = 1 sets it to higher priority
level.
3 PT1 This bit defines the Timer 1 interrupt priority. PT1 = 1 sets it to higher priority
level.
2 PX1 This bit defines the External interrupt 1 priority. PX1 = 1 sets it to higher priority
level.
1 PT0 This bit defines the Timer 0 interrupt priority. PT0 = 1 sets it to higher priority
level.
0 PX0 This bit defines the External interrupt 0 priority. PX0 = 1 sets it to higher priority
level.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 46 - Revision A4.0
SLAVE ADDRESS MASK ENABLE
Bit: 7 6 5 4 3 2 1 0
SADEN.7 SADEN.6 SADEN.5 SADEN.4 SADEN.3 SADEN.2 SADEN.1 SADEN.0
Mnemonic: SADEN Address: B9h
BIT NAME FUNCTION
7-0 SADEN
This register enables the Automatic Address Recognition feature of the Serial
port. When a bit in the SADEN is set to 1, the same bit location in SADDR will be
compared with the incoming serial port data. When SADEN.n is 0, then the bit
becomes don't care in the comparison. This register enables the Automatic
Address Recognition feature of the Serial port. When all the bits of SADEN are
0, interrupt will occur for an y incoming address.
SLAVE ADDRESS MASK ENABLE 1
Bit: 7 6 5 4 3 2 1 0
SADEN1.7 SADEN1.6 SADEN1.5 SADEN1.4 SADEN1.3 SADEN1.2 SADEN1.1 SADEN1.0
Mnemonic: SADEN1 Address: BAh
BIT NAME FUNCTION
7-0 SADEN1
This register enables the Automatic Address Recognition feature of the Serial
port 1. When a bit in the SADEN1 is set to 1, the same bit location in SADDR1
will be compared with the incoming serial port data. When SADEN1.n is 0, then
the bit becomes don't care in the comparison. This register enables the
Automatic Address Recognition feature of the Serial port. When all the bits of
SADEN1 are 0, interrupt will occur for any incoming addres s.
PWM OUTPUT OVERRIDE CONTROL REGISTERS
Bit: 7 6 5 4 3 2 1 0
POVM.7 POVM.6 POVM.5 POVM.4 POVM.3 POVM.2 POVM.1 POVM.0
Mnemonic: POVM Address: BBh
BIT NAME FUNCTION
7-0 POVM PWM Override Mode enable bits;
0: The PWM output follows the corresponding PWM generator.
1: The PWM output is equal to corresponding bit in POVD.
PWM OUTPUT STATE REGISTERS
Bit: 7 6 5 4 3 2 1 0
POVD.7 POVD.6 POVD.5 POVD.4 POVD.3 POVD.2 POVD.1 POVD.0
Mnemonic: POVD Address: BCh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 47 - Revision A4.0
BIT NAME FUNCTION
7-0 POVD
PWM Override Data represents the value of PWM[7:0] respectively in override
mode.
1 = Output on PWM I/O pin is ACTIVE when the corresponding PWM output
override bit is cleared.
0 = Output on PWM I/O pin is INACTIVE when the corresponding PWM outp ut
override bit is cleared.
PWM PIN OUTPUT SOURCE SELECT
Bit: 7 6 5 4 3 2 1 0
PIO7 PIO6 PIO5 PIO4 PIO3 PIO2 PIO1 PIO0
Mnemonic: PIO Address: BDh
BIT NAME FUNCTION
7-0 PIO.x
Select pin output source from PWM or I/O register; x=0~7; PIOn is effective only
when option bit PWMOE/PWMEE/PWM6E/PWM7E is in enabled status. Reset
value=0;
1 = Correspondent I/O pin with high source/sink current.
0 = PWMn output; n=0~7 with high source/sink current.
PWM OUTPUT ENABLE REGISTER
Bit: 7 6 5 4 3 2 1 0
PWM7EN PWM6EN PWM5EN PWM4EN PWM3EN PWM2EN PWM1EN PWM0EN
Mnemonic: PWMEN Address: BEh
BIT NAME FUNCTION
6,4,2,0 PWMeEN Set high to enable even PWM output; e = 0,2,4,6; Reset value=0;
1 = Enable PWM output.
0 = Disable PWM output.
7,5,3,1 PWMoEN Set high to enable odd PWM output; o = 1,3,5,7; Reset value=0;
1 = Enable PWM output.
0 = Disable PWM output.
PWM 4 HIGH BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - PWM4.11 PWM4.10 PWM4.9 PWM4.8
Mnemonic: PWM4H Address: BFh
BIT NAME FUNCTION
7~4 - Reserved
3~0 PWM4.11 ~PWM4.8 The PWM 4 Register bit 11~8.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 48 - Revision A4.0
SERIAL PORT CONTROL 1
Bit: 7 6 5 4 3 2 1 0
SM0_1/FE_1 SM1_1 SM2_1 REN_1 TB8_1 RB8_1 TI_1 RI_1
Mnemonic: SCON1 Address: C0h
BIT NAME FUNCTION
7 SM0_1/
FE_1
Serial Port 1 mode select bit 0 or Framing Error Flag: This bit is controlled by the
SMOD0 bit in the PCON register.
(SM0) See table below.
(FE) This bit indicates an invalid stop bit. It must be manually cleared by software.
6 SM1_1
Serial Port 1 mode select bit 1. See table below.
5 SM2_1
Serial Port Clock or Multi-Processor Communication.
(Mode 0) This bit controls the serial port clock. If set to zero, the serial port runs at a
divide-by-12 clock of the oscillator. This is compatible with the standard 8051/52. If
set to one, the serial clock is a divide-by-4 clock of the oscillator.
(Mode 1) If SM2_1 is set to one, RI_1 is not activated if a valid stop bit is not
received.
(Modes 2 / 3) This bit enables multi-processor communication. If SM2_1 is set to
one, RI_1 is not activated if RB8_1, the ninth data bit, is zero.
4 REN_1
Receive enable:
1: Enable serial reception.
0: Disable serial reception.
3 TB8_1
(Modes 2 / 3) This is the 9th bit to transmit. This bit is set by software.
2 RB8_1
(Mode 0) No function.
(Mode 1) If SM2_1 = 0, RB8_1 is the stop bit that wa s received.
(Modes 2 / 3) This is the 9th bit that was received.
1 TI_1
Transmit interrupt flag: This flag is set by the hardware at the end of the 8th bit in
mode 0 or at the beginning of the stop bit in the other modes during serial
transmission. This bit must be cleared by software.
0 RI_1
Receive interrupt flag: This flag is set by the hardware at the end of the 8th bit in
mode 0 or halfway through the stop bits in the other modes during serial reception.
However, SM2_1 can restrict this behavior. This bit can only be cleared by
software.
SM1_1, SM0_1: Mode Select bits:
SM0_1 SM1_1 MODE DESCRIPTION LENGTH BAUD RATE
0 0 0 Synchronous 8
Tclk divided by 4 or 12
0 1 1 Asynchronous 10
Variable
1 0 2 Asynchronous 11
Tclk divided by 32 or 64
1 1 3 Asynchronous 11
Variable
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 49 - Revision A4.0
SERIAL DATA BUFFER 1
Bit: 7 6 5 4 3 2 1 0
SBUF_1.7 SBUF_1.6 SBUF_1.5 SBUF_1.4 SBUF_1.3 SBUF_1.2 SBUF_1.1 SBUF_1.0
Mnemonic: SBUF1 Address: C1h
BIT NAME FUNCTION
7-0 SBUF_1
For Serial Port 1. Serial data is read from or written to this location. It actually
consists of two separate 8 bit registers. One is the receive buffer, and the other
is the transmit buffer. Any read access gets data from the receive data buffer,
while write access i s to the transmit data buffer.
TIMER 3 MODE CONTROL
Bit: 7 6 5 4 3 2 1 0
ENLD ICEN2 ICEN1 ICEN0 T3CR - - -
Mnemonic: T3MOD Address: C2h
BIT NAME FUNCTION
7 ENLD Enable reloads from RCAP3 registers to timer 3 counters.
6 ICEN2
Capture 2 External Enable. This bit enables the capture/reload function on the
IC2 pin. An edge trigger (programmable by CAPCON0.CCT2[1:0] bits) detected
on the IC2 pin will result in capture from free running timer 3 counters to input
capture 2 registers, or reload from RCAP3 registers to timer 3 count ers.
1 = Enable.
0 = Disable.
5 ICEN1
Capture 1 External Enable. This bit enables the capture/reload function on the
IC1 pin. An edge trigger (programmable by CAPCON0.CCT1[1:0] bits) detected
on the IC1 pin will result in capture from free running timer 3 counters to input
capture 1 registers, or reload from RCAP3 registers to timer 3 count ers.
1 = Enable.
0 = Disable.
4 ICEN0
Capture 0 External Enable. This bit enables the capture/reload function on the
IC0 pin. An edge trigger (programmable by CAPCON0.CCT0[1:0] bits) detected
on the IC0 pin will result input capture from free running timer 3 counters to input
capture 0 registers, or reload from RCAP3 registers to timer 3 count ers.
1 = Enable.
0 = Disable.
3 T3CR
Timer 3 Capture Reset. In the Timer 3 Capture Mode this bit enables/disables
hardware automatically reset timer 3 while the value in TL3 and TH3 have been
transferred into the input capture register (CCLx, CCHx). Priority is given to
T3CR to reset counter after capture.
2-0 - Reserved.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 50 - Revision A4.0
TIMER 3 CONTROL
Bit: 7 6 5 4 3 2 1 0
TF3 - - - - TR3
- CMP/RL3
Mnemonic: T3CON Address: C3h
BIT NAME FUNCTION
7 TF3 Timer 3 overflows flag. This bit is set when Timer 3 overflows. It is cleared only
by software and set by hardware.
6-3 - Reserved.
2 TR3 Timer 3 Run Control. This bit enables/disables the operation of timer 3. Halting
this will preserve the current count in TH3, TL3.
1 - Reserved.
0 CMP/RL3
Compare/Reload Select. This bit determines whether the Timer 3 will be use for
compare or reload function.
0 = Timer 3 as reload mode, TF3 indicates the overflo w flag
1 = Timer 3 as compare m ode, TF3 indicates the compare match flag.
POWER MANAGEMENT REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - - ALEOFF - DME0
Mnemonic: PMR Address: C4h
BIT NAME FUNCTION
7-3 - Reserved.
2 ALEOFF
This bit disables the expression of the ALE signal on the device pin during all on
board program and data memory accesses. External memory accesses will
automatically enable ALE independent of ALEOFF. ALEOFF=0: ALE expression
is enabled. ALEOFF=1: ALE expressio n is disabled.
1 - Reserved.
0 DME0 This bit determines the on chip MOVX SRAM to be enabled or disabled. Set this
bit to 1 will enable the on chip 2 KB MOVX SRAM.
FAULT SAMPLING TIME REGISTER
Bit: 7 6 5 4 3 2 1 0
SCMP1 SCMP0 SFP1 SFP0 SFCEN SFCST SFCDIR LSBD
Mnemonic: FSPLT Address: C5h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 51 - Revision A4.0
BIT NAME FUNCTION
7-6 SCMP [1:0]
Smart fault compare value selector (read/write):
00 = 4
01 = 16
10 = 64
11 = 128
5-4 SFP[1:0]
Smart fault sampling frequency selector (read/write):
00 = FOSC/4
01 = FOSC/8
10 = FOSC/16
11 = FOSC/128
3 SFCEN Smart fault/brake counter enable (read/write):
0 = Disable, and clear inte rnal smart fault counter.
1 = Enable smart fault detector.
2 SFCST Smart fault/brake counter status (read only):
0 = Counter is non-active.
1 = Counter is active.
1 SFCDIR
Smart fault/brake counters direction status (read only):
0 = Down counting.
1 = Up counting.
0 LSBD Low level smart brake detector:
0 = Disable low level sma rt brake detector.
1 = Enable low level smart brake detector. It will be cleared by software.
ADC PIN SELECT
Bit: 7 6 5 4 3 2 1 0
ADCPS.7 ADCPS.6 ADCPS.5 ADCPS.4 ADCPS.3 ADCPS.2 ADCPS.1 ADCPS.0
Mnemonic: ADCPS Address: C6h
BIT NAME FUNCTION
7-0 ADCPS
ADC input pin select. There are 8 ADC input pins shared with P1.0~P1.7. Its’
functions are controlled by the bit value in ADCPS. Set the bit to switch the
corresponding pin to ADC input port; clear the bit to disable the pin to perform
ADC input port. The reset value is 00H.
BIT CORRESPONDING PIN BIT CORRESPONDING PIN
ADCPS.0 P1.0 ADCPS.4 P1.4
ADCPS.1 P1.1 ADCPS.5 P1.5
ADCPS.2 P1.2 ADCPS.6 P1.6
ADCPS.3 P1.3 ADCPS.7 P1.7
TIMED ACCESS
Bit: 7 6 5 4 3 2 1 0
TA.7 TA.6 TA.5 TA.4 TA.3 TA.2 TA.1 TA.0
Mnemonic: TA Address: C7h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 52 - Revision A4.0
BIT NAME FUNCTION
7-0 TA
The Timed Access register controls the access to protected bits. To access
protected bits, the user must first write AAh to TA. This must be immediately
followed by a write of 55h to TA. Now a window is opened in the protected bits
for three machine cycles, during which the user can write to these bits. For detail
data, please refer "TIMED ACCESS PROTECTION" section.
TIMER 2 CONTROL
Bit: 7 6 5 4 3 2 1 0
TF2 EXF2 RCLK TCLK EXEN2 TR2 2TC/ 2RLCP/
Mnemonic: T2CON Address: C8h
BIT NAME FUNCTION
7 TF2
Timer 2 overflows flag. This bit is set when Timer 2 overflows. It is also set when
the count is equal to the capture register in down count mode. It can be set only
if RCLK and TCLK are both 0. It is cleared only by software. Software can also
set this bit.
6 EXF2
Timer 2 External Flag. A negative transition on the T2EX pin (P4.1) or timer 2
underflow/overflow will cause this flag to set based on 2RLCP/, EXEN2 and
DCEN bits. If EXF2 is set by a negative transition, this flag must be cleared by
software. Setting this bit in software or detection of a negative transition on T2EX
pin will force a timer interrupt if enabled.
5 RCLK
Receive clock Flag. This bit determines the serial port time-base when receiving
data in serial modes 1 or 3. If it is 0, then timer 1 overflow is used for baud rate
generation, else timer 2 overflow is used. Setting this bit forces timer 2 in baud
rate generator mode.
4 TCLK
Transmit clock Flag: This bit determines the serial port time-base when
transmitting data in mode 1 and 3. If it is set to 0, the timer 1 overflow is used to
generate the baud rate clock; else timer 2 overflow is used. Setting this bit forces
timer 2 in baud rate generator mode.
3 EXEN2
Timer 2 External Enable. This bit enables the capture/reload function on the
T2EX pin if Timer 2 is not generating baud clocks for the serial port. If this bit is
0, then the T2EX pin will be ignored, else a negative transition detected on the
T2EX pin will result in capture or reload.
2 TR2 Timer 2 Run Control. This bit enables/disables the operation of timer 2. Halting
this will preserve the current count in TH2, TL2.
1 TC/
Counter/Timer select. This bit determines whether timer 2 will function as a timer
or a counter. Independent of this bit, the timer will run at 2 clocks per tick when
used in baud rate generator mode. If it is set to 0, then timer 2 operates as a
timer at a speed depending on T2M bit (CKCON.5), else, it will count negative
edges on T2 pin.
0 RL2CP/
Capture/Reload Select. This bit determines whether the capture or reload
function will be used for timer 2. If either RCLK or TCLK is set, this bit will not
function and the timer will function in an auto-reload mode following each
overflow. If the bit is 0 then auto-reload will occur when timer 2 overflows or a
falling edge is detected on T2EX if EXEN2 =1. If this bit is 1, then timer 2
captures will occur when a falling edge is detected on T2EX if EXEN2=1.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 53 - Revision A4.0
TIMER 2 MODE CONTROL
Bit: 7 6 5 4 3 2 1 0
HC5 HC4 HC3 HC2 T2CR - - DCEN
Mnemonic: T2MOD Address: C9h
BIT NAME FUNCTION
7 HC5 Hardware clears INT5 flag. Setting this bit allows the flag of External Interrupt 5
to be automatically cleared by hardware while entering the interrupt service
routine.
6 HC4 Hardware clears INT4 flag. Setting this bit allows the flag of External Interrupt 4
to be automatically cleared by hardware while entering the interrupt service
routine.
5 HC3 Hardware clears INT3 flag. Setting this bit allows the flag of External Interrupt 3
to be automatically cleared by hardware while entering the interrupt service
routine.
4 HC2 Hardware clears INT2 flag. Setting this bit allows the flag of External Interrupt 2
to be automatically cleared by hardware while entering the interrupt service
routine.
3 T2CR Timer 2 Capture Reset. In the Timer 2 Capture Mode this bit enables/disables
hardware automatically reset timer 2 while the value in TL2 and TH2 have been
transferred into the capture register.
2-1 - Reserved.
0 DCEN Down Count Enable. This bit, in conjunction with the T2EX pin, controls the
up/down direction that timer 2 counts in 16-bit auto -reload mo de.
TIMER 2 CAPTURE LSB
Bit: 7 6 5 4 3 2 1 0
RCAP2L.
7 RCAP2L.
6 RCAP2L.
5 RCAP2L.
4 RCAP2L.
3 RCAP2L.
2 RCAP2L.
1 RCAP2L.
0
Mnemonic: RCAP2L Address: CAh
BIT NAME FUNCTION
7-0 RCAP2L Timer 2 Capture LSB: This register is used to capture the TL2 value when a
timer 2 is configured in capture mode. RCAP2L is also used as the LSB of a 16
bit reload value when timer 2 is configur ed in auto reload mode.
TIMER 2 CAPTURE MSB
Bit: 7 6 5 4 3 2 1 0
RCAP2H.
7 RCAP2H.
6 RCAP2H.
5 RCAP2H.
4 RCAP2H.
3 RCAP2H.
2 RCAP2H.
1 RCAP2H.
0
Mnemonic: RCAP2H Address: CBh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 54 - Revision A4.0
BIT NAME FUNCTION
7-0 RCAP2H Timer 2 Capture HSB: This register is used to capture the TH2 value when a
timer 2 is configured in capture mode. RCAP2H is also used as the HSB of a 16
bit reload value when timer 2 is configur ed in auto reload mode.
TIMER 2 LSB
Bit: 7 6 5 4 3 2 1 0
TL2.7 TL2.6 TL2.5 TL2.4 TL2.3 TL2.2 TL2.1 TL2.0
Mnemonic: TL2 Address: CCh
TL2 Timer 2 LSB
TIMER 2 MSB
Bit: 7 6 5 4 3 2 1 0
TH2.7 TH2.6 TH2.5 TH2.4 TH2.3 TH2.2 TH2.1 TH2.0
Mnemonic: TH2 Address: CDh
TH2 Timer 2 MSB
PWM CONTROL REGISTER 2
Bit: 7 6 5 4 3 2 1 0
BKCH BKPS BPEN BKEN FP1 FP0 PMOD1 PMOD0
Mnemonic: PWMCON2 Address: CEh
BIT NAME FUNCTION
7 BKCH See table below for BKCH settings.
6 BKPS
Select which brake condition triggers brake flag. LSBD bit is described in SFR
FSPLT.
BKPS LSBD Description
0 0 0 = Brake is asserted if P1.1 is low.
1 0 1 = Brake is asserted if P1.1 is high
x 1 Low level smart brake detector.
5 BPEN See table below for BPEN settings.
4 BKEN 0 = The Brake is never asserted.
1 = The Brake is enabled.
BIT NAME FUNCTION
3-2 FP[1:0]
Select PWM frequency prescaler select bits. The clock source of prescaler,
Fpwm is in phase with Fosc if PWMRUN=1.
FP[1:0] Fpwm
00 FOSC
01 FOSC /2
10 FOSC /4
11 FOSC /16
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 55 - Revision A4.0
Continued
BIT NAME FUNCTION
1-0 PMOD[1:0]
PWM Mode selects bits:
PMOD[1:0] Description
00 Edge-aligned mode. (up counter)
01 Single-shot mode. (up counter)
10 Center aligned mode (up-down counter)
11 Reserved
Brake Condition Table
BPEN BKCH BRAKE CONDITION
0 0
Brake On, (Software brake and keeping brake).
Software brake condition. When active (BPEN=BKCH=0, and BKEN=1), PWM
output follows PWMnB setting. This brake has no effect on PWMRUN bit;
therefore, internal PWM generator continues to run. When the brake is released,
the state of PWM output depends on the current state of PWM generator output
during the release.
0 1
Brake On, when PWM is not running (PWMRUN=0), the PWM output condition is
follow PWMnB setting. When the brake is released (by disabling BKEN = 0), the
PWM output resumes to the state when PWM generator stop running prior to
enabling the brake.
Brake Off, when PWM is running (PWMRUN=1).
1 0
Brake On, when Brake Pin asserted, PWM output follows PWMnB setting. The
PWMRUN will be clear.
External pin brake condition. When active (by external pin), PWM output follows
PWMnB setting. PWMRUN will be cleared by hardware. BKF flag will be set.
When the brake is released (by de-asserting the external pin + disabling BKEN =
0), the PWM output resumes to the state of the PWM generator output prior to
the brake.
1 1
This brake condition (by Brake Pin) causes BKF to be set, but PWM generator
continues to run. The PWM output does not follow PWMnB, instead it output
continuously as per normal without affected by the brake.
PWM 4 LOW BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
PWM4.7 PWM4.6 PWM4.5 PWM4.4 PWM4.3 PWM4.2 PWM4.1 PWM4.0
Mnemonic: PWM4L Address: CFh
PWM4.7-0 PWM4 Low Bits Register.
PROGRAM STATUS WORD
Bit: 7 6 5 4 3 2 1 0
CY AC F0 RS1 RS0 OV F1 P
Mnemonic: PSW Address: D0h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 56 - Revision A4.0
BIT NAME FUNCTION
7 CY Carry flag. Set for an arithmetic operation which results in a carry being
generated from the ALU. It is also used as the accumulator for the bit operations.
6
AC Auxiliary carry: Set when the previous operation resulted in a carry (during
addition) or a borrow (during subtraction) from the high order nibbl e.
5 F0 User flag 0. A general purpose flag that can be set or cleared by the by softwa re .
4-3 RS.1-0
Register ban k selects bits:
RS1 RS2 Register Bank Address
0 0 0 00-07h
0 1 1 08-0Fh
1 0 2 10-17h
1 1 3 18-1Fh
2 OV Overflow flag. Set when a carry was generated from the seventh bit but not from
the 8th bit as a result of the previous operation or vice-versa.
1 F1 User Flag 1. General purpose flag that can be set or cleared by the user by
software.
0 P Parity flag. Set/cleared by hardware to indicate odd/even number of 1's in the
accumulator.
PWMP COUNTER HIGH BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - PWMP.11 PWMP.10 PWMP.9 PWMP.8
Mnemonic: PWMPH Address: D1h
BIT NAME FUNCTION
7-4 - Reserved.
3-0 PWMP.11~PWMP.8 PWM Counter Register bits 11 ~8.
PWM 0 HIGH BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - PWM0.11 PWM0.10 PWM0.9 PWM0.8
Mnemonic: PWM0H Address: D2h
BIT NAME FUNCTION
7~4 - Reserved.
3~0 PWM0.11
~PWM0.8 The PWM 0 Register bit 11~8.
NVM DATA
Bit: 7 6 5 4 3 2 1 0
NVMDAT.7 NVMDAT.6 NVMDAT.5 NVMDAT.4 NVMDAT.3 NVMDAT.2 NVMDAT.1 NVMDAT.0
Mnemonic: NVMDAT Address: D3h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 57 - Revision A4.0
BIT NAME FUNCTION
7~0 NVMDAT.7~NVMDAT.0 The NVM data write register. The read NVM data is by MOVX instruction.
QEI CONTROL REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - DISIDX DIR QEIM1 QEIM0 QEIEN
Mnemonic: QEICON Address: D4h
BIT NAME FUNCTION
7-5 - Reserved.
4 DISIDX
Disable Input Capture 2 edge detection function:
0 = Enable IC2 edge detection function (default).
1 = Disable IC2 edge dete ction fun ction .
This bit is effective when QEIEN=1.
3 DIR
Direction index of motion detection bit:
1 = Forward (Up-counting).
0 = Backward (Down-counting).
This bit is writable and rea dable.
2-1 QEIM[1:0]
QEI mode select bits:
QEIM1 QEIM0 Descriptions
0 0 X4 free-counting mode
0 1 X2 free-counting mode
1 0 X4 compare-counting mode
1 1 X2 compare-counting mode
0 QEIEN Input module mode select bit:
0 = Input module performs Input Capture Functions. (Default value ).
1 = Input module works as QEI.
PWM 2 HIGH BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - PWM2.11 PWM2.10 PWM2.9 PWM2.8
Mnemonic: PWM2H Address: D5h
BIT NAME FUNCTION
7~4 - Reserved
3~0 PWM2.11 ~PWM2.8 PWM 2 Register bit 11~8.
PWM 6 HIGH BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - PWM6.11 PWM6.10 PWM6.9 PWM6.8
Mnemonic: PWM6H Address: D6h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 58 - Revision A4.0
BIT NAME FUNCTION
7~4 - Reserved
3~0 PWM6.11 ~PWM6.8 PWM 6 Register bit 11~8.
WATCHDOG CONTROL 2
Bit: 7 6 5 4 3 2 1 0
- - - - - - - STRLD
Mnemonic: WDCON2 Address: D7h
BIT NAME FUNCTION
7-6 - Reserved.
0 STRLD Set this bit, CPU will restart from LD Flash EPROM after watchdog reset. Clear
this bit, CPU will restart from AP Flash EPROM after watchdog reset. This
register is protected by timer acce ss (TA) register.
WATCHDOG CONTROL
Bit: 7 6 5 4 3 2 1 0
- POR - - WDIF WTRF EWT RWT
Mnemonic: WDCON Address: D8h
BIT NAME FUNCTION
7 - Reserved.
6 POR Power-on Reset Flag. Hardware will set this flag on a power up condition. This
flag can be read or written by software. A write by software is the only way to
clear this bit once it is set.
5-4 - Reserved.
3 WDIF Watchdog Timer Interrupt Flag. This bit is set by hardware to indicate that the
time-out period has elapsed and invoke watch dog timer interrupt if enabled
(EWDI=1). This bit must be clear by software.
2 WTRF
Watchdog Timer Reset Flag. Hardware will set this bit when the watchdog timer
causes a reset if EWT= 1. Software can read it but must clear it manually. A
power-on reset will also clear the bit. This bit helps software in determining the
cause of a reset
1 EWT Enable Watchdog timer Reset. Setting this bit will enable the Watchdog timer
Reset function after 512 clocks delay from time out and setting WTRF flag.
0 RWT
Reset Watchdog Timer. This bit restarts the watchdog timer and helps in
putting the watchdog timer into a know state. It also helps in resetting the
watchdog timer before a time-out occurs. If EWDI (EIE.4) is set, an interrupt will
occur when time-out. If EWT is set, 512 clocks after the time-out, a system
reset will occur and CPU starts from 0000H. This bit is self-clearing. The
WDCON SFR is set to a 0x0x0xx0b on an external reset. WTRF is set to a 1 on
a Watchdog timer reset, but to a 0 on power on resets. WTRF is not altered by
an external reset. POR is set to 1 by a power-on reset. EWT is cleared to 0 on
a Power-on reset and unaf fected by other resets.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 59 - Revision A4.0
The WDCON SFR is set to x0xx 0000b on an external reset. WTRF is set to a 1 on a Watchdog timer
reset, but to a 0 on power on resets. POR is set to 1 by a power-on reset. EWT is cleared to 0 on a
Power-on reset, reset pin reset, Watch Dog Timer reset and ISP reset.
All the bits in this SFR have unrestricted read access. The bits of POR, WDIF, EWT and RWT require
Timed Access (TA) procedure to write. The remaining bits have unrestricted write accesses. Please
refer TA register description.
PWMP COUNTER LOW BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
PWMP.7 PWMP.6 PWMP.5 PWMP.4 PWMP.3 PWMP.2 PWMP.1 PWMP.0
Mnemonic: PWMPL Address: D9h
BIT NAME FUNCTION
7~0 PWMP.7 ~PWMP.0 PWM Counter Low Bits Register.
PWM0 LOW BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
PWM0.7 PWM0.6 PWM0.5 PWM0.4 PWM0.3 PWM0.2 PWM0.1 PWM0.0
Mnemonic: PWM0L Address: DAh
BIT NAME FUNCTION
7~0 PWM0.7 ~PWM0.0 PWM 0 Low Bits Register.
NVM LOW BYTE ADDRESS
Bit: 7 6 5 4 3 2 1 0
NVMADDR
L.7 NVMADDR
L.6 NVMADDR
L.5 NVMADDR
L.4 NVMADDR
L.3 NVMADDR
L.2 NVMADDR
L.1 NVMADDR
L.0
Mnemonic: NVMADDRL Address: DBh
BIT NAME FUNCTION
7~0 NVMADDRL.7~
NVMADDRL.0 NVM low byte address.
PWM CONTROL REGISTER 1
Bit: 7 6 5 4 3 2 1 0
PWMRUN Load PWMF CLRPWM PWM6I PWM4I PWM2I PWM0I
Mnemonic: PWMCON1 Address: DCh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 60 - Revision A4.0
BIT NAME FUNCTION
7 PWMRUN
0 = The PWM is not running.
1 = The PWM counter is running.
6 Load
This bit is auto cleared by hardware after the PWMP and PWMn are transferred
to counter and compare register:
0 = The registers value of PWMP and PWMn is never loaded to counter and
compare registers.
1 = The PWMP and PWMn registers load value to counter and compare
registers at the counter und erflow/match.
5 PWMF
12 bit counter overflow flag:
0 = The 12-bit counter is not underflo w/match.
1 = The 12-bit counter is underflow/match. It will be set by hardware and cleared
by software.
4 CLRPWM
1 = Clear 12-bit PWM counter to 000H. It will be automatically clear by
hardware.
3-0 PWMxI 0 = PWM0 o utput is non-inverted.
1 = PWM0 output is inverted.
Note: x = 0,2,4,6.
PWM 2 LOW BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
PWM2.7 PWM2.6 PWM2.5 PWM2.4 PWM2.3 PWM2.2 PWM2.1 PWM2.0
Mnemonic: PWM2L Address: DDh
BIT NAME FUNCTION
7~0 PWM2.7 ~PWM2.0 PWM 2 Low Bits Register.
PWM 6 LOW BITS REGISTER
Bit: 7 6 5 4 3 2 1 0
PWM6.7 PWM6.6 PWM6.5 PWM6.4 PWM6.3 PWM6.2 PWM6.1 PWM6.0
Mnemonic: PWM6L Address: DEh
BIT NAME FUNCTION
7~0 PWM6.7 ~PWM6.0 PWM 6 Low Bits Register.
PWM CONTROL REGISTER 3
Bit: 7 6 5 4 3 2 1 0
PWM7B PWM6B PWM5B PWM4B PWM3B PWM2B PWM1B PWM0B
Mnemonic: PWMCON3 Address: DFh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 61 - Revision A4.0
BIT NAME FUNCTION
7-0 PWMxB 0 = The PWM0 output is low, when Brake is asserted.
1 = The PWM0 output is high, when Brake is as serted.
Note: x = 0~7
ACCUMULATOR
Bit: 7 6 5 4 3 2 1 0
ACC.7 ACC.6 ACC.5 ACC.4 ACC.3 ACC.2 ACC.1 ACC.0
Mnemonic: ACC Address: E0h
BIT NAME FUNCTION
7-0 ACC The A or ACC register is the standard 8032 accumulator
ADC CONTROL REGISTER
Bit: 7 6 5 4 3 2 1 0
ADCEN - ADCEX ADCI ADCS AADR.2 AADR.1 AADR.0
Mnemonic: ADCCON Address: E1h
BIT NAME FUNCTION
7 ADCEN Enable A/D Converter Function. Set ADCEN to logic high to enable ADC block.
6 - Reserved.
5 ADCEX Enable external start control of ADC conversion by a rising edge from P4.0.
ADCEX=0: Disable external start. ADCE X=1: Enable external start control.
4 ADCI A/D Converting Complete/Interrupt Flag. This flag is set when ADC conversion is
completed. The ADC interrupt is requested if the interrupt is enabled. ADCI is set
by hardware and cleared by software only.
3 ADCS
ADC Start and Status: Set this bit to start an A/D conversion. It may also be set
by STADC if ADCEX is 1. This signal remains high while the ADC is busy and is
reset right after ADCI is set.
Notes:
1. It is recommended to clear ADCI before ADCS is set. However, if ADCI is
cleared and ADCS is set at the same time, a new A/D conversion may start
on the same channel.
2. Software clearing of ADCS will abort conversion in progress.
3. ADC cannot start a new conversion while ADCS or ADCI is high.
2-0 AADR
Select and enable analog input ch annel from ADC0 to ADC7.
AADR[2:0] ADC selected input AADR[2:0] ADC selected input
000 ADCCH0 (P1. 0) 100 ADCCH4 (P1.4)
001 ADCCH1 (P1. 1) 101 ADCCH5 (P1.5)
010 ADCCH2 (P1. 2) 110 ADCCH6 (P1.6)
011 ADCCH3 (P1. 3) 111 ADCCH7 (P1.7)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 62 - Revision A4.0
The ADCI and ADCS control the ADC conversion as below:
ADCI ADCS ADC STATUS
0 0 ADC not busy; A conversion can be started.
0 1 ADC busy; Start of a new conversion is blocked.
1 0 Conversion completed; Start of a new conversion requires ADCI = 0.
1 1 This is an internal temporary state that user can ignore it.
ADC CONVERTER RESULT HIGH REGISTER
Bit: 7 6 5 4 3 2 1 0
ADC.9 ADC.8 ADC.7 ADC.6 ADC.5 ADC.4 ADC.3 ADC.2
Mnemonic: ADCH Address: E2h
BIT NAME FUNCTION
7-0 ADC[9:2] 8 MSB of 10 bit A/D conversion result. ADCH is a read only register.
ADC CONVERTER RESULT LOW REGISTER
Bit: 7 6 5 4 3 2 1 0
ADCLK.1 ADCLK.0 - - - - ADC.1 ADC.0
Mnemonic: ADCL Address: E3h
BIT NAME FUNCTION
7-6 ADCLK
ADC Clock Frequency Select. The 10 bit ADC needs a clock to drive the
converting that the clock frequency may not over 4MHz. ADCLK[1:0] controls the
frequency of the clock to ADC block:
ADCLK.1 ADCLK.0 ADC Clock Frequency
0 0 Crystal clock / 4 (Default)
0 1 Crystal clock / 8
1 0 Crystal clock / 16
1 1 Reserved
1-0 ADC 2 LSB of 10-bit A/D conversion result. Both bits are read only.
PWM DEAD-TIME CONTROL REGISTER 1
Bit: 7 6 5 4 3 2 1 0
PDTC1.7 PDTC1.6 PDTC1.5 PDTC1.4 PDTC1.3 PDTC1.2 PDTC1.1 PDTC1.0
Mnemonic: PDTC1 Address: E5h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 63 - Revision A4.0
BIT NAME FUNCTION
7-6 PDTC1
Dead-time clock frequen cy (FDT) prescaler select bits.
PDTC1.7 PDTC1.6 FDT
0 0 FOSC/2
0 1 FOSC/4
1 0 FOSC/8
1 1 FOSC/16
5-0 PDTC1 Dead time counter. Unsigned 6 bit dead time value bits for Dead Time Unit.
Dead-time = FDT * (PDTC1 [5:0]+1)
PWM DEAD-TIME CONTROL REGISTER 0
Bit: 7 6 5 4 3 2 1 0
PDTC0.7 PDTC0.6 PDTC0.5 PDTC0.4 PDTC0.3 PDTC0.2 PDTC0.1 PDTC0.0
Mnemonic: PDTC0 Address: E6h
BIT NAME FUNCTION
7-4 PDTC0
Control complementary PWM to delay a dead-time at every rising edge or falling
edge. Reset value = 0.
1 = Dead-time is inserted at falling edge.
0 = Dead-time is inserted at rising e dge.
PDTC0.4 - controls the pair of (PWM0, PWM1).
PDTC0.5 - controls the pair of (PWM2, PWM3).
PDTC0.6 - controls the pair of (PWM4, PWM5).
PDTC0.7 - controls the pair of (PWM6, PWM7).
3-0 PDTC0
Enable dead-time insertion; Dead-time insertion is only active when the pair of
complementary PWM is enabled. Reset value=0. If dead-time insertion is
inactive, the outputs of pin pair are complementary without any delay.
1 = Programmable dead -time is inserted into the pair signals of comparator output
to delay the pair signals change fro m low to high.
0 = Disable dead-tim e insertion.
PDTC0.0 - enables the dead-time insertion on the pin pair (PWM0, PWM1).
PDTC0.1 - enables the dead-time insertion on the pin pair (PWM2, PWM3).
PDTC0.2 - enables the dead-time insertion on the pin pair (PWM4, PWM5).
PDTC0.3 - enables the dead-time insertion on the pin pair (PWM6, PWM7).
PWM CONTROL REGISTER 4
Bit: 7 6 5 4 3 2 1 0
PWMEOM PWMOOM PWM6OM PWM7OM - - - BKF
Mnemonic: PWMCON4 Address: E7h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 64 - Revision A4.0
BIT NAME FUNCTION
7 PWMEOM
PWM Channel 0, 2 and 4 Output Mode.
0 = Disable PWM channels 0, 2 and 4 to pwm output pins.
1 = Enable PWM channels 0, 2 and 4 to pwm output pins.
6 PWMOOM
PWM Channel 1, 3 and 5 Output Mode.
0 = Disable PWM channels 1, 3 and 5 to pwm output pins.
1 = Enable PWM channels 1, 3 and 5 to pwm output pins.
5 PWM6OM
PWM Channel 6 Output Mode.
0 = Disable PWM channel 6 to pwm output pin.
1 = Enable PWM channel 6 to pwm output pin.
4 PWM7OM
PWM Channel 7 Output Mode.
0 = Disable PWM channel 7 to pwm output pin.
1 = Enable PWM channel 7 to pwm output pin.
3-1 - Reserved.
0 BKF The External Brake Pin Flag.
0 = The PWM is not brake.
1 = The PWM is brake by external brake pin. It will be cleared by software.
Together with option bits (PWMEE and PWMOE), PWMEOM, PWMOOM, PWM6OM and PWM7OM
control the PWM pin structure, as follow;
PWMEE/PWMOE
(OPTION BITS)
PWMEOM/PWMOOM
/PWM6OM/PWM7OM
PIO.X
(X = 0-7) PIN STRUCTURES
X 0 X Tri-state
1 (Disable) 1 X Quasi (I/O output)
0 (Enable) 1 0 Push Pull (PWM output)
0 (Enable) 1 1 Push Pull (I/O output)
Table 7-2: PWM pin structures (during internal rom execution)
PWMEE/PWMOE
(OPTION BITS)
PWMEOM/PWMOOM
/PWM6OM/PWM7OM
PIO.X
(X = 0-7)
PIN
OUTPUT PIN STRUCTURES
1 (Disable) X X External
access Push Pull
0 (Enable) X X
External
access Push Pull (str ong)
Table 7-3: PWM pin structures (during external rom execution)
Note: PWMEOM/PWMOOM/PWM6OM/PWM7OM are cleared to zero when CPU in reset state.
Thus, the port pins that multi-function with PWM will be tristated on default. User is required to set
the bits to 1 to enable GPIO/PWM outputs.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 65 - Revision A4.0
EXTENDED INTERRUPT ENABLE
Bit: 7 6 5 4 3 2 1 0
ES1 EX5 EX4 EWDI EX3 EX2 - EI2C
Mnemonic: EIE Address: E8h
BIT NAME FUNCTION
7 ES1 Enable Serial Port 1 interrupts.
6 EX5 Enable External Interrupt 5.
5 EX4 Enable External Interrupt 4.
4 EWDI Enable Watchdog timer interrupt.
3 EX3 Enable External Interrupt 3.
2 EX2 Enable External Interrupt 2.
1 - Reserved.
0 EI2C Enable I2C interrupt.
I2C CONTROL REGISTER
Bit: 7 6 5 4 3 2 1 0
- ENS STA STO SI AA I2CIN -
Mnemonic: I2CON Address: E9h
BIT NAME FUNCTION
7 - Reserved.
6 ENS I2C serial function block enable bit. When ENS=1 the I2C serial function
enables. The port latches of SDA and SCL must be set to logic high.
5 STA I2C START Flag. Setting STA to logic 1 to enter master mode, the I2C hardware
sends a START or repe at START condition to bus when the bus is free.
4 STO
I2C STOP Flag. In master mode, setting STO to transmit a STOP condition to
bus then I2C hardware will check the bus condition if a STOP condition is
detected this flag will be cleared by hardware automatically. In a slave mode,
setting STO resets I2C hardware to the defined “not addre s sed” slave mode.
3 SI I2C Interrupt Flag. When a new SIO state is present in the S1STA register, the
SI flag is set by hardware, and if the EA and EI2C bits are both set, the I2C
interrupt is requested. SI must be cleared by softwar e.
2 AA
Assert Acknowledge Flag. When AA=1 an acknowledged (low level to SDA) will
be returned during the acknowledge clock pulse on the SCL line. When AA=0 an
acknowledged (high level to SDA) will be returned during the acknowledge clock
pulse on the SCL line.
1 I2CIN By default it is zero and input are allows to come in through SDA pin. As when it
is 1 input is disallow and to prevent leakage current. During Power-Down mode
input is disallow.
0 - Reserved.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 66 - Revision A4.0
I2C ADDRESS REGISTER
Bit: 7 6 5 4 3 2 1 0
I2ADDR.7 I2ADDR.6 I2ADDR.5 I2ADDR.4 I2ADDR.3 I2ADDR.2 I2ADDR.1 GC
Mnemonic: I2ADDR Address: EAh
BIT NAME FUNCTION
7-1 I2ADDR
I2C Slave Address. The contents of the register are irrelevant when I2C is in
master mode. In the slave mode, the seven most significant bits must be loaded
with the MCU’s own slave address. The I2C hardware will react if the contents of
I2ADDR are matched with the received slave address.
0 GC Enable General Call Function. The GC bit is set the I2C port hardware will respond
to General Call address (00H). Clear G C bit to disable general call function.
NVM HIGH BYTE ADDRESS
Bit: 7 6 5 4 3 2 1 0
- - - - - NVMADDR
H.10 NVMADDR
H.9 NVMADDR
H.8
Mnemonic: NVMADDRH Address: EBh
BIT NAME FUNCTION
7-3 - Reserved.
2-0 NVMADDRH.10 ~
NVMADDRH.8 NVM High byte address
I2C DATA REGISTER
Bit: 7 6 5 4 3 2 1 0
I2DAT.7 I2DAT.6 I2DAT.5 I2DAT.4 I2DAT.3 I2DAT.2 I2DAT.1 I2DAT.0
Mnemonic: I2DAT Address: ECh
I2DAT.7-0 The data register of I2C channel.
I2C STATUS REGISTER
Bit: 7 6 5 4 3 2 1 0
B7 B6 B5 B4 B3 0 0 0
Mnemonic: I2STATUS Address: EDh
BIT NAME FUNCTION
7-0 I2STATUS
The Status Register of I2C. The three least significant bits are always 0. The five
most significant bits contain the status code. There are 23 possible status
codes. When I2STATUS contains F8H, no serial interrupt is requested. All other
I2STATUS values correspond to defined I2C states. When each of these states
is entered, the I2C1 interrupt is requeste d (SI = 1). A valid status code is present
in I2STATUS one machine cycle after SI is set by hardware and is still present
one machine cycle after SI has been reset by software. In addition, states 00H
stands for a Bus Error. A Bus Error occurs when a START or STOP condition is
present at an illegal position in the formation frame. Example of illegal position
are during the serial transfer of an address byte, a data byte or an acknowledge
bit.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 67 - Revision A4.0
I2C BAUD RATE CONTROL REGISTER
Bit: 7 6 5 4 3 2 1 0
I2CLK.7 I2CLK.6 I2CLK.5 I2CLK.4 I2CLK.3 I2CLK.2 I2CLK.1 I2CLK.0
Mnemonic: I2CLK Address: EEh
BIT NAME FUNCTION
7-0 I2CLK I2C clock rate control.
I2C TIMER COUNTER REGISTER
Bit: 7 6 5 4 3 2 1 0
- - - - - ENTI DIV4 TIF
Mnemonic: I2TIMER Address: EFh
BIT NAME FUNCTION
7-3 - Reserved.
2 ENTI Enable I2C 14-bits Time-out Counter. Setting ENTI to logic high will firstly reset
the time-out counter and then start up counting. Clearing ENTI disables the 14-
bit time-out counter. ENTI can be set to logic high only when SI=0.
1 DIV4 I2C Time-out Counter Clock Frequency Selection.
0 = the clock frequency is coherent to the system clock Fosc.
1 = the clock frequency is Fosc/4.
0 TIF I2C Time-out Flag. When the time-out counter overflows hardware will set this
flag and request the I2C interrupt if I2C interrupt is enabled (EI2C=1). This bit
must be cleared by software.
B REGISTER
Bit: 7 6 5 4 3 2 1 0
B.7 B.6 B.5 B.4 B.3 B.2 B.1 B.0
Mnemonic: B Address: F0h
BIT NAME FUNCTION
7-0 B The B register is the standard 8032 accumulator.
SERIAL PERIPHERAL CONTROL REGISTER
Bit: 7 6 5 4 3 2 1 0
SSOE SPE LSBFE MSTR CPOL CPHA SPR1 SPR0
Mnemonic: SPCR Address: F3h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 68 - Revision A4.0
BIT NAME FUNCTION
7 SSOE Slave Select Output Enable Bit. The SS output feature is enabled only in master
mode by asserting the SSOE bit. In slave mode (/SS) input is not affected by
SSOE bit. See table below.
6 SPE
Serial Peripheral System Enable Bit.
When the SPE bit is set, SPI block functions is enable. When MODF is set, SPE
always reads 0.
0 = SPI system disabled.
1 = SPI system enabled.
5 LSBFE
LSB - First Enable. This bit does not affect the position of the MSB and LSB in
the data register. Reads and writes of the data register always have the MSB in
bit 7. In master mode, a change of this bit will abort a transmission in progress
and force the SPI system into idle state.
1 = Data is transferred least significant bit first.
0 = Data is transferred most significant bit first.
4 MSTR
Master Mode Select Bit. It is customary to have an external pull-up resistor on
lines that are driven by open drain devices.
0 = Slave mode.
1 = Master mode.
3 CPOL Clock Polarity Bit. When the clock polarity bit is cleared and data is not being
transferred, the SPCLK pin of the master device has a steady state low value.
When CPOL is set, SPCLK idles high.
2 CPHA CPHA Clock Phase Bit. The clock phase bit, in conjunction with the CPOL bit,
controls the clock-data relationship between master and slave. The CPHA bit
selects one of two different clocking protocols.
1-0 SPR SPI Baud Rate Selection Bits. These bits specify the SPI baud rates.
DRSS SSOE MASTER MODE SLAVE MODE
0 0 /SS input ( With Mode Fault ) /SS Input ( Not affected by SSOE )
0 1 Reserved /SS Input ( Not affected by SSOE )
1 0 /SS General purpose I/O ( No Mode
Fault ) /SS Input ( Not affected by SSOE )
1 1 /SS output ( No Mode Fault ) /SS Input ( Not affected by SSOE )
Note: In master mode, a change of LSBFE, MSTR, CPOL, CPHA and SPR [1:0] will abort a
transmission in progress and force th e SPI system into idle state.
SERIAL PERIPHERAL STATUS REGISTER
Bit: 7 6 5 4 3 2 1 0
SPIF WCOL SPIOVF MODF DRSS - - -
Mnemonic: SPSR Address: F4h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 69 - Revision A4.0
BIT NAME FUNCTION
7 SPIF
SPI Interrupt Complete Flag. SPIF is set upon completion of data transfer
between this device and external device or when new data has been received
and copied to the SPDR. If SPIF goes high, and if ESPI is set, a serial peripheral
interrupt is generated. When SPIF is set; it must be clear by software and
attempts to write SPDR are inhibited if SPIF set.
6 WCOL Write Collision Flag. If a writer collision occurs on SPI bus, WCOL is set to high
by hardware. WCOL must be clear by software.
5 SPIOVF
SPI overrun flag. SPIOVF is set if a new character is received before a
previously received character is read from SPDR. Once this bit is set it will
prevent SPDR register form excepting new data and must be cleared first be fore
any new data can be written. This flag is clear by software.
0 = No overrun.
1 = Overrun detected.
4 MODF SPI Mode Error Interrupt Status Flag. MODF is set when hardware detects m ode
fault. This bit is cleared by software.
3 DRSS Data Register Slave Select. Refer to above table in SPCR regi ster.
2-0 - Reserved.
Note: Bits WCOL, MODF and SPIF are cleared by software writing “0” to them.
SERIAL PERIPHERAL DATA I/O REGISTER
Bit: 7 6 5 4 3 2 1 0
SPD.7 SPD.6 SPD.5 SPD.4 SPD.3 SPD.2 SPD.1 SPD.0
Mnemonic: SPDR Address: F5h
BIT NAME FUNCTION
7-0 SPD
SPDR is used when transmitting or receiving data on serial bus. Only a write to
this register initiates transmission or reception of a byte, and this only occurs in
the master device. A read of the SPDR is actually a read of a buffer. To prevent
an overrun and the loss of the byte that caused the overrun, the first SPIF must
be cleared by the time a second transfer of data from the shift Register to the
read buffer is initiated.
I2C SLAVE ADDRESS MASK ENABLE
Bit: 7 6 5 4 3 2 1 0
I2CSADE
N.7 I2CSADE
N.6 I2CSADE
N.5 I2CSADE
N.4 I2CSADE
N.3 I2CSADE
N.2 I2CSADE
N.1 I2CSADE
N.0
Mnemonic: I2CSADEN Address: F6h
BIT NAME FUNCTION
7-0 I2CSADEN
This register enables the Automatic Address Recognition feature of the I2C.
When a bit in the I2CSADEN is set to 1, the same bit location in I2CSADDR1
will be compared with the incoming serial port data. When I2CSADEN.n is 0,
the bit becomes don't care in the comparison. This register enables the
Automatic Address Recognition feature of the I2C. When all the bits of
I2CSADEN are 0, interrupt will occur for any incoming address. The default
value is 0xFE.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 70 - Revision A4.0
EXTENDED INTERRUPT HIGH PRIORITY
Bit: 7 6 5 4 3 2 1 0
PS1H PX5H PX4H PWDIH PX3H PX2H - PI2CH
Mnemonic: EIPH Address: F7h
BIT NAME FUNCTION
7 PS1H Serial Port 1 Interrupt High Priority. PS1H = 1 sets it to highest priority level.
6 PX5H External Interrupt 5 High Priority. PX5H = 1 sets it to highest priority level.
5 PX4H External Interrupt 4 High Priority. PX4H = 1 sets it to highest priority level.
4 PWDIH Watchdog Timer Interrupt High Priority. PWDIH = 1 sets it to highest priority
level.
3 PX3H External Interrupt 3 High Priority. PX3H = 1 sets it to highest priority level.
2 PX2H External Interrupt 2 High Priority. PX2H = 1 sets it to highest priority level.
1 - Reserved.
0 PI2CH I2C Interrupt High Pri ority. PI2CH = 1 sets it to highest priority level.
EXTENDED INTERRUPT PRIORITY
Bit: 7 6 5 4 3 2 1 0
PS1 PX5 PX4 PWDI PX3 PX2 - PI2C
Mnemonic: EIP Address: F8h
BIT NAME FUNCTION
7 PS1 Serial Port 1 Interrupt Priority.
6 PX5 External Interrupt 5 Priority.
5 PX4 External Interrupt 4 Priority.
4 PWDI Watchdog Timer Interrupt Priority.
3 PX3 External Interrupt 3 Priority.
2 PX2 External Interrupt 2 Priority.
1 - Reserved.
0 PI2C I2C Interrupt Priority.
EXTENDED INTERRUPT ENABLE 1
Bit: 7 6 5 4 3 2 1 0
- - ENVM ECPTF ET3 EBK EPWM ESPI
Mnemonic: EIE1 Address: F9h
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 71 - Revision A4.0
BIT NAME FUNCTION
7-6 - Reserved.
5 ENVM NVM Interrupt Enable Bit.
0 = Disable NVM interrupt.
1 = Enable NVM interrupt.
4 ECPTF Capture Interrupt Enable Bit.
0 = Disable External capture/reload interrupt.
1 = Enable External capture/reload interrupt.
3 ET3 Timer 3 Interrupt Enable Bit.
0 = Disable Timer 3 Interrupt.
1 = Enable Timer 3 Interrupt.
2 EBK Brake Interrupt Enable Bit.
0 = Brake interrupt disable.
1 = Brake interrupt enable.
1 EPWM PWM Period Interrupt Enable Bit.
0 = PWM period system interrupts di sabled.
1 = PWM period system interrupts e nabled.
0 ESPI
Serial Peripheral Interrupt Enable Bit. Set the ESPI bit to 1 to request a
hardware interrupt sequence each time the SPIF/MODF status flag is set.
0 = SPI system interrupts disabled.
1 = SPI system interrupts enabled.
EXTENDED INTERRUPT PRIORITY 1
Bit: 7 6 5 4 3 2 1 0
- -
PNVMI PCPTF PT3 PBKF PPWMF PSPI
Mnemonic: EIP1 Address: FAh
BIT NAME FUNCTION
7-6 - Reserved.
5 PNVMI NVM interrupt Priority
4 PCPTF Capture/reload Interrupt Priority.
3 PT3 Timer 3 Interrupt Priority.
2 PBKF PWM Brake Interrupt Priority.
1 PPWMF PWM period Interrupt Priority.
0 PSPI SPI Interrupt Priority.
INPUT CAPTURE 0/PULSE READ COUNTER LOW REGISTER
Bit: 7 6 5 4 3 2 1 0
CCL0.7/
PCNTL.7 CCL0.6/
PCNTL.6 CCL0.5/
PCNTL.5 CCL0.4/
PCNTL.4 CCL0.3/
PCNTL.3 CCL0.2/
PCNTL.2 CCL0.1/
PCNTL.1 CCL0.0/
PCNTL.0
Mnemonic: CCL0/PCNTL Address: FBh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 72 - Revision A4.0
PCNTL must be read first before reading at PCNTH as reading PCNTL will latch the PLSCNTH
automatically into PCNTH; otherwise inaccurate result is read when reading PCNTH first as it will not
latch the PLSCNTL data into PCNTL.
INPUT CAPTURE 0/PULSE READ COUNTER HIGH REGISTER
Bit: 7 6 5 4 3 2 1 0
CCH0.7/
PCNTH.7 CCH0.6/
PCNTH.6 CCH0.5/
PCNTH.5 CCH0.4/
PCNTH.4 CCH0.3/
PCNTH.3 CCH0.2/
PCNTH.2 CCH0.1/
PCNTH.1 CCH0.0/
PCNTH.0
Mnemonic: CCH0/PCNTH Address: FCh
PCNTL must be read first before reading at PCNTH as reading PCNTL will latch the PLSCNTH
automatically into PCNTH.
INPUT CAPTURE 1/PULSE COUNTER LOW REGISTER
Bit: 7 6 5 4 3 2 1 0
CCL1.7/
PLSCNT
L.7
CCL1.6/
PLSCNT
L.6
CCL1.5/
PLSCNT
L.5
CCL1.4/
PLSCNT
L.4
CCL1.3/
PLSCNT
L.3
CCL1.2/
PLSCNT
L.2
CCL1.1/
PLSCNT
L.1
CCL1.0/
PLSCNT
L.0
Mnemonic: CCL1/PLSCNTL Address: FDh
INPUT CAPTURE 1/PULSE COUNTER HIGH REGISTER
Bit: 7 6 5 4 3 2 1 0
CCH1.7/
PLSCNT
H.7
CCH1.6/
PLSCNT
H.6
CCH1.5/
PLSCNT
H.5
CCH1.4/
PLSCNT
H.4
CCH1.3/
PLSCNT
H.3
CCH1.2/
PLSCNT
H.2
CCH1.1/
PLSCNT
H.1
CCH1.0/
PLSCNT
H.0
Mnemonic: CCH1/PLSCNTH Address: FEh
INTERRUPT CONTROL
Bit: 7 6 5 4 3 2 1 0
- - INT5CT1 INT5CT0 INT4CT1 INT4CT0 INT3CT1 INT3CT0
Mnemonic: INTCTRL Address: FFh
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 73 - Revision A4.0
BIT NAME FUNCTION
7-6 - Reserved.
5-4 INT5CT
Interrupt 5 edge select:
INT5CT1 INT5CT0 Description
0 0 Rising edge trigger.
0 1 Falling edge trigger.
1 0 Rising and falling edge trigger.
1 1 Reserved.
3-2 INT4CT
Interrupt 4 edge select:
INT4CT1 INT4CT0 Description
0 0 Rising edge trigger.
0 1 Falling edge trigger.
1 0 Rising and falling edge trigger.
1 1 Reserved.
1-0 INT3CT
Interrupt 3 edge select:
INT3CT1 INT3CT0 Description
0 0 Rising edge trigger.
0 1 Falling edge trigger.
1 0 Rising and falling edge trigger.
1 1 Reserved.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 74 - Revision A4.0
8. INSTRUCTION SET
The W79E22X SERIES executes all the instructions of the standard 8051/52 family. The operations of
these instructions, as well as their effects on flag and status bits, are exactly the same. However, the
timing of these instructions is different in two ways. Firstly, the W79E22X SERIES machine cycle is
four clock periods, while the standard-8051/52 machine cycle is twelve clock periods. Secondly, the
W79E22X SERIES can fetch only once per machine cycle (i.e., four clocks per fetch), while the
standard 8051/52 can fetch twice per machine cycle (i.e., six clocks per fetch).
The timing differences create an advantage for the W79E22X SERIES. There is only one fetch per
machine cycle, so the number of machine cycles is usually equal to the number of operands in the
instruction. (Jumps and calls do require an additional cycle to calculate the new address.) As a result,
the W79E22X SERIES reduces the number of dummy fetches and wasted cycles, and therefore
improves overall efficiency, compared to the standard 8051/52.
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
NOP 00 1 1 4 12 3
ADD A, R0 28 1 1 4 12 3
ADD A, R1 29 1 1 4 12 3
ADD A, R2 2A 1 1 4 12 3
ADD A, R3 2B 1 1 4 12 3
ADD A, R4 2C 1 1 4 12 3
ADD A, R5 2D 1 1 4 12 3
ADD A, R6 2E 1 1 4 12 3
ADD A, R7 2F 1 1 4 12 3
ADD A, @R0 26 1 1 4 12 3
ADD A, @R1 27 1 1 4 12 3
ADD A, direct 25 2 2 8 12 1. 5
ADD A, #data 24 2 2 8 12 1.5
ADDC A, R0 38 1 1 4 12 3
ADDC A, R1 39 1 1 4 12 3
ADDC A, R2 3A 1 1 4 12 3
ADDC A, R3 3B 1 1 4 12 3
ADDC A, R4 3C 1 1 4 12 3
ADDC A, R5 3D 1 1 4 12 3
ADDC A, R6 3E 1 1 4 12 3
ADDC A, R7 3F 1 1 4 12 3
ADDC A, @R0 36 1 1 4 12 3
ADDC A, @R1 37 1 1 4 12 3
ADDC A, direct 35 2 2 8 12 1.5
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 75 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
ADDC A, #data 34 2 2 8 12 1.5
SUBB A, R0 98 1 1 4 12 3
SUBB A, R1 99 1 1 4 12 3
SUBB A, R2 9A 1 1 4 12 3
SUBB A, R3 9B 1 1 4 12 3
SUBB A, R4 9C 1 1 4 12 3
SUBB A, R5 9D 1 1 4 12 3
SUBB A, R6 9E 1 1 4 12 3
SUBB A, R7 9F 1 1 4 12 3
SUBB A, @R0 96 1 1 4 12 3
SUBB A, @R1 97 1 1 4 12 3
SUBB A, direct 95 2 2 8 12 1.5
SUBB A, #data 94 2 2 8 12 1.5
INC A 04 1 1 4 12 3
INC R0 08 1 1 4 12 3
INC R1 09 1 1 4 12 3
INC R2 0A 1 1 4 12 3
INC R3 0B 1 1 4 12 3
INC R4 0C 1 1 4 12 3
INC R5 0D 1 1 4 12 3
INC R6 0E 1 1 4 12 3
INC R7 0F 1 1 4 12 3
INC @R0 06 1 1 4 12 3
INC @R1 07 1 1 4 12 3
INC direct 05 2 2 8 12 1.5
INC DPTR A3 1 2 8 24 3
DEC A 14 1 1 4 12 3
DEC R0 18 1 1 4 12 3
DEC R1 19 1 1 4 12 3
DEC R2 1A 1 1 4 12 3
DEC R3 1B 1 1 4 12 3
DEC R4 1C 1 1 4 12 3
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 76 - Revision A4.0
DEC R5 1D 1 1 4 12 3
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 77 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
DEC R6 1E 1 1 4 12 3
DEC R7 1F 1 1 4 12 3
DEC @R0 16 1 1 4 12 3
DEC @R1 17 1 1 4 12 3
DEC direct 15 2 2 8 12 1.5
MUL AB A4 1 5 20 48 2.4
DIV AB 84 1 5 20 48 2.4
DA A D4 1 1 4 12 3
ANL A, R0 58 1 1 4 12 3
ANL A, R1 59 1 1 4 12 3
ANL A, R2 5A 1 1 4 12 3
ANL A, R3 5B 1 1 4 12 3
ANL A, R4 5C 1 1 4 12 3
ANL A, R5 5D 1 1 4 12 3
ANL A, R6 5E 1 1 4 12 3
ANL A, R7 5F 1 1 4 12 3
ANL A, @R0 56 1 1 4 12 3
ANL A, @R1 57 1 1 4 12 3
ANL A, direct 55 2 2 8 12 1.5
ANL A, #data 54 2 2 8 12 1.5
ANL direct, A 52 2 2 8 12 1.5
ANL direct, #data 53 3 3 12 24 2
ORL A, R0 48 1 1 4 12 3
ORL A, R1 49 1 1 4 12 3
ORL A, R2 4A 1 1 4 12 3
ORL A, R3 4B 1 1 4 12 3
ORL A, R4 4C 1 1 4 12 3
ORL A, R5 4D 1 1 4 12 3
ORL A, R6 4E 1 1 4 12 3
ORL A, R7 4F 1 1 4 12 3
ORL A, @R0 46 1 1 4 12 3
ORL A, @R1 47 1 1 4 12 3
ORL A, direct 45 2 2 8 12 1.5
ORL A, #data 44 2 2 8 12 1.5
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 78 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
ORL direct, A 42 2 2 8 12 1.5
ORL direct, #data 43 3 3 12 24 2
XRL A, R0 68 1 1 4 12 3
XRL A, R1 69 1 1 4 12 3
XRL A, R2 6A 1 1 4 12 3
XRL A, R3 6B 1 1 4 12 3
XRL A, R4 6C 1 1 4 12 3
XRL A, R5 6D 1 1 4 12 3
XRL A, R6 6E 1 1 4 12 3
XRL A, R7 6F 1 1 4 12 3
XRL A, @R0 66 1 1 4 12 3
XRL A, @R1 67 1 1 4 12 3
XRL A, direct 65 2 2 8 12 1.5
XRL A, #data 64 2 2 8 12 1.5
XRL direct, A 62 2 2 8 12 1.5
XRL direct, #data 63 3 3 12 24 2
CLR A E4 1 1 4 12 3
CPL A F4 1 1 4 12 3
RL A 23 1 1 4 12 3
RLC A 33 1 1 4 12 3
RR A 03 1 1 4 12 3
RRC A 13 1 1 4 12 3
SWAP A C4 1 1 4 12 3
MOV A, R0 E8 1 1 4 12 3
MOV A, R1 E9 1 1 4 12 3
MOV A, R2 EA 1 1 4 12 3
MOV A, R3 EB 1 1 4 12 3
MOV A, R4 EC 1 1 4 12 3
MOV A, R5 ED 1 1 4 12 3
MOV A, R6 EE 1 1 4 12 3
MOV A, R7 EF 1 1 4 12 3
MOV A, @R0 E6 1 1 4 12 3
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 79 - Revision A4.0
MOV A, @R1 E7 1 1 4 12 3
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 80 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
MOV A, direct E5 2 2 8 12 1.5
MOV A, #data 74 2 2 8 12 1.5
MOV R0, A F8 1 1 4 12 3
MOV R1, A F9 1 1 4 12 3
MOV R2, A FA 1 1 4 12 3
MOV R3, A FB 1 1 4 12 3
MOV R4, A FC 1 1 4 12 3
MOV R5, A FD 1 1 4 12 3
MOV R6, A FE 1 1 4 12 3
MOV R7, A FF 1 1 4 12 3
MOV R0, direct A8 2 2 8 12 1.5
MOV R1, direct A9 2 2 8 12 1.5
MOV R2, direct AA 2 2 8 12 1.5
MOV R3, direct AB 2 2 8 12 1.5
MOV R4, direct AC 2 2 8 12 1.5
MOV R5, direct AD 2 2 8 12 1.5
MOV R6, direct AE 2 2 8 12 1.5
MOV R7, direct AF 2 2 8 12 1.5
MOV R0, #data 78 2 2 8 12 1.5
MOV R1, #data 79 2 2 8 12 1.5
MOV R2, #data 7A 2 2 8 12 1.5
MOV R3, #data 7B 2 2 8 12 1.5
MOV R4, #data 7C 2 2 8 12 1.5
MOV R5, #data 7D 2 2 8 12 1.5
MOV R6, #data 7E 2 2 8 12 1.5
MOV R7, #data 7F 2 2 8 12 1.5
MOV @R0, A F6 1 1 4 12 3
MOV @R1, A F7 1 1 4 12 3
MOV @R0, direct A6 2 2 8 12 1.5
MOV @R1, direct A7 2 2 8 12 1.5
MOV @R0, #data 76 2 2 8 12 1.5
MOV @R1, #data 77 2 2 8 12 1.5
MOV direct, A F5 2 2 8 12 1.5
MOV direct, R0 88 2 2 8 12 1.5
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 81 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS. 8032
SPEED RATIO
MOV direct, R1 89 2 2 8 12 1.5
MOV direct, R2 8A 2 2 8 12 1.5
MOV direct, R3 8B 2 2 8 12 1.5
MOV direct, R4 8C 2 2 8 12 1.5
MOV direct, R5 8D 2 2 8 12 1.5
MOV direct, R6 8E 2 2 8 12 1.5
MOV direct, R7 8F 2 2 8 12 1.5
MOV direct, @R0 86 2 2 8 12 1.5
MOV direct, @R1 87 2 2 8 12 1.5
MOV direct, direct 85 3 3 12 24 2
MOV direct, #data 75 3 3 12 24 2
MOV DPTR, #data 16 90 3 3 12 24 2
MOVC A, @A+DPTR 93 1 2 8 24 3
MOVC A, @A+PC 83 1 2 8 24 3
MOVX A, @R0 E2 1 2 - 9 8 - 36 24 3 - 0.66
MOVX A, @R1 E3 1 2 - 9 8 - 36 24 3 - 0.66
MOVX A, @DPTR E0 1 2 - 9 8 - 36 24 3 - 0.66
MOVX @R0, A F2 1 2 - 9 8 - 36 24 3 - 0.66
MOVX @R1, A F3 1 2 - 9 8 - 36 24 3 - 0.66
MOVX @DPTR, A F0 1 2 - 9 8 - 36 24 3 - 0.66
PUSH direct C0 2 2 8 24 3
POP direct D0 2 2 8 24 3
XCH A, R0 C8 1 1 4 12 3
XCH A, R1 C9 1 1 4 12 3
XCH A, R2 CA 1 1 4 12 3
XCH A, R3 CB 1 1 4 12 3
XCH A, R4 CC 1 1 4 12 3
XCH A, R5 CD 1 1 4 12 3
XCH A, R6 CE 1 1 4 12 3
XCH A, R7 CF 1 1 4 12 3
XCH A, @R0 C6 1 1 4 12 3
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 82 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
XCH A, @R1 C7 1 1 4 12 3
XCHD A, @R0 D6 1 1 4 12 3
XCHD A, @R1 D7 1 1 4 12 3
XCH A, direct C5 2 2 8 12 1.5
CLR C C3 1 1 4 12 3
CLR bit C2 2 2 8 12 1.5
SETB C D3 1 1 4 12 3
SETB bit D2 2 2 8 12 1.5
CPL C B3 1 1 4 12 3
CPL bit B2 2 2 8 12 1.5
ANL C, bit 82 2 2 8 24 3
ANL C, /bit B0 2 2 6 24 3
ORL C, bit 72 2 2 8 24 3
ORL C, /bit A0 2 2 6 24 3
MOV C, bit A2 2 2 8 12 1.5
MOV bit, C 92 2 2 8 24 3
ACALL addr11
71, 91,
B1, 11,
31, 51,
D1, F1
2 3 12 24 2
LCALL addr16 12 3 4 16 24 1.5
RET 22 1 2 8 24 3
RETI 32 1 2 8 24 3
AJMP ADDR11
01, 21,
41, 61,
81, A1,
C1, E1
2 3 12 24 2
LJMP addr16 02 3 4 16 24 1.5
JMP @A+DPTR 73 1 2 6 24 3
SJMP rel 80 2 3 12 24 2
JZ rel 60 2 3 12 24 2
JNZ rel 70 2 3 12 24 2
JC rel 40 2 3 12 24 2
JNC rel 50 2 3 12 24 2
JB bit, rel 20 3 4 16 24 1.5
JNB bit, rel 30 3 4 16 24 1.5
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 83 - Revision A4.0
Continued
OP-CODE HEX
CODE BYTES
W79E22X
SERIES
MACHINE
CYCLE
W79E22X
SERIES
CLOCK
CYCLES
8032
CLOCK
CYCLES
W79E22X
SERIES VS.
8032 SPEED
RATIO
JBC bit, rel 10 3 4 16 24 1.5
CJNE A, direct, rel B5 3 4 16 24 1.5
CJNE A, #data, rel B4 3 4 16 24 1.5
CJNE @R0, #data, rel B6 3 4 16 24 1.5
CJNE @R1, #data, rel B7 3 4 16 24 1.5
CJNE R0, #data, rel B8 3 4 16 24 1.5
CJNE R1, #data, rel B9 3 4 16 24 1.5
CJNE R2, #data, rel BA 3 4 16 24 1.5
CJNE R3, #data, rel BB 3 4 16 24 1.5
CJNE R4, #data, rel BC 3 4 16 24 1.5
CJNE R5, #data, rel BD 3 4 16 24 1.5
CJNE R6, #data, rel BE 3 4 16 24 1.5
CJNE R7, #data, rel BF 3 4 16 24 1.5
DJNZ R0, rel D8 2 3 12 24 2
DJNZ R1, rel D9 2 3 12 24 2
DJNZ R5, rel DD 2 3 12 24 2
DJNZ R2, rel DA 2 3 12 24 2
DJNZ R3, rel DB 2 3 12 24 2
DJNZ R4, rel DC 2 3 12 24 2
DJNZ R6, rel DE 2 3 12 24 2
DJNZ R7, rel DF 2 3 12 24 2
DJNZ direct, rel D5 3 4 16 24 1.5
Table 8-1: Instruction Set for W79E22X SERIES
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 84 - Revision A4.0
8.1 Instruction Timing
This section is important because some applications use software instructions to generate timing
delays. It also provides more information about timing differences between the W79E22X SERIES and
the standard 8051/52.
In W79E22X SERIES, each machine cycle is four clock periods long. Each clock period is called a
state, and each machine cycle consists of four states: C1, C2 C3 and C4, in order. Both clock edges
are used for internal timing, so the duty cycle of the clock should b e as close to 50% as possible.
The W79E22X SERIES does one op-code fetch per machine cycle, so, in most instructions, the
number of machine cycles required is equal to the number of bytes in the instruction. There are 256
available op-codes. 128 of them are single-cycle instructions, so many op-codes are executed in just
four clock periods. Some of the other op-codes are two-cycle instructions, and most of these have
two-byte op-codes. However, there are some instructions that have one-byte instructions yet take two
cycles to execute. One important example is the MOVX instruction.
In the standard 8051/52, the MOVX instruction is always two machine cycles long. However, in the
W79E22X SERIES, the duration of this instruction is controlled by the software. It can vary from two to
nine machine cycles long, and, RD andWR strobe lines are elongated proportionally. This is called
stretching, and it gives a lot of flexibility when accessing fast and slow peripherals. It also reduces the
amount of external circuitry and software overhea d.
The rest of the instructions are three-, four- or five-cycle instructions. At the end of this section, there
are timing diagrams that provide an example of each type of instruction (single-cycle, two-cycle, …).
In summary, there are five types of instructions in the W79E22X SERIES, based on the number of
machine cycles, and each machine cycle is four clock periods long. The standard 8051/52 has only
three types of instructions, based on the number of machine cycles, but each machine cycle is twelve
clock periods long. As a result, even though the number of categories is higher, each instruction in the
W79E22X SERIES runs 1.5 to 3 times faster, based on the number of clock periods, than it does in
the standard 8051/52.
Single Cycle
C4
C3C2
C1
CLK
ALE
PSEN
AD7-0
PORT 2
A7-0
Address A15-8
Data_ in D7-0
Figure 8-1: Single Cycle Instruction Timing
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 85 - Revision A4.0
Instruction Fetch C4C3C2C1
OP-CODE
Address A15-8Address A15-8
ALE
PSEN
PC
AD7-0
PORT 2
CLK
Operand Fetch
C4C3C2
C1
OPERANDPC+1
Figure 8-2: Two Cycles Instruction Timing
OPERANDOPERAND A7-0A7-0 A7-0OP-CODE
Address A15-8Address A15-8Address A15-8
Operand FetchOperand FetchInstruction Fetch
C2 C3 C4C2 C3 C4C4C3C2 C1C1C1
CLK
ALE
PSEN
AD7-0
PORT 2
Figure 8-3: Three Cycles Instruction Timing
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 86 - Revision A4.0
OPERAND
OPERANDOPERAND
OP-CODE
Address A15-8Address A15-8Address A15-8
Address A15-8
A7-0
A7-0
A7-0
A7-0
Operand FetchOperand FetchOperand FetchInstruction Fetch
C2C1 C4C3C2
C1
CLK
ALE
PSEN
AD7-0
Port 2
C4C3 C2C1 C4C3 C2C1 C4C3
Figure 8-4: Four Cycles Instruction Timing
OPERANDOPERAND
OPERAND
OP-CODE
Address A15-8Address A15-8Address A15-8Address A15-8
A7-0A7-0A7-0A7-0
Operand Fetch Operand Fetch
Operand FetchOperand FetchInstruction Fetch
C2C1 C4C3C2C1
CLK
ALE
PSEN
AD7-0
PORT 2
C4C3 C2C1 C4C3 C2C1 C4C3 C2C1 C4C3
OPERAND
A7-0
Address A15-8
Figure 8-5: Five Cycles Instruction Timing
8.1.1 External Data Memory Access Timing
The timing for the MOVX instruction is another feature of the W79E22X SERIES. In the standard
8051/52, the MOVX instruction has a fixed execution time of 2 machine cycles. However, in W79E22X
SERIES, the duration of the access can be controlled by the user.
The instruction starts off as a normal op-code fetch that takes four clocks. In the next machine cycle,
W79E22X SERIES puts out the external memory address, and the actual access occurs. The user
can control the duration of this access by setting the stretch value in CKCON, bits 2 – 0. As shown in
the table below, these three bits can range from zero to seven, resulting in MOVX instructions that
take two to nine machine cycles. The default value is one, resulting in a MOVX instruction of three
machine cycl es.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 87 - Revision A4.0
Stretching only affects the MOVX instruction. There is no effect on any other instruction or its timing; it
is as if the state of the CPU is held for the desired period. The timing waveforms when the stretch
value is zero, one, and two are shown b elow.
M2 M1 M0 MACHINE
CYCLES
RD OR WR
STROBE WIDTH
IN CLOCKS
RD OR WR
STROBE WIDTH
@ 25 MHZ
RD OR WR
STROBE WIDTH
@ 40 MHZ
0 0 0 2 2 80 nS 50 nS
0 0 1 3 (default) 4 160 nS 100 nS
0 1 0 4 8 320 nS 200 nS
0 1 1 5 12 480 nS 300 nS
1 0 0 6 16 640 nS 400 nS
1 0 1 7 20 800 nS 500 nS
1 1 0 8 24 960 nS 600 nS
1 1 1 9 28 1120 nS 700 nS
Table 8-2: Data Memory Cycle Stretch Values
Next Instruction
Machine Cycle
Second
Machine cycle
First
Machine cycle
Last Cycle
of Previous
Instruction
C4
PORT 2
PORT 0
WR
PSEN
ALE
CLK
C3C2
D0-D7
A0-A7
D0-D7
A0-A7
D0-D7A0-A7
D0-D7
A15-A8
A15-A8A15-A8A15-A8
A0-A7
C1 C4C3C2C1 C4C3C2C1 C4C3C2C1
MOVX instruction cycle
Next Inst. Read
Next Inst.
Address
MOVX Data out
MOVX Data
Address
MOVX Inst.
Address MOVX Inst.
Figure 8-6: Data Memory Write with Stretch Value = 0
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 88 - Revision A4.0
Next Instruction
Machine Cycle
Third
Machine Cycle
Second
Machine Cycle
First
Machine Cycle
Last Cycle
of Previous
Instruction
C4
PORT 2
PORT 0
WR
PSEN
ALE
CLK
C3C2
D0-D7
A0-A7
D0-D7
A0-A7
D0-D7
A0-A7
D0-D7
A15-A8A15-A8A15-A8A15-A8
A0-A7
C1 C4C3C2C1 C4C3C2C1 C4C3C2C1
MOVX instruction cycle
Next Inst.
Read
Next Inst.
Address MOVX Data out
MOVX Data
Address
MOVX Inst.
Address
MOVX Inst.
C4C3C2C1
Figure 8-7: Data Memory Write with Stretch Value = 1
Next
Instruction
Machine Cycle
Fourth
Machine Cycle
Third
Machine Cycle
Second
Machine Cycle
First
Machine Cycle
Last Cycle
of Previous
Instruction
C4
PORT 2
PORT 0
WR
PSEN
ALE
CLK
C3C2
D0-D7
A0-A7
D0-D7
A0-A7
D0-D7
A0-A7
D0-D7
A15-A8A15-A8A15-A8A15-A8
A0-A7
C1 C4C3C2C1 C4C3C2C1 C4C3C2C1
MOVX instruction cycle
Next Inst.
Read
Next Inst.
Address MOVX Data out
MOVX Data
Address
MOVX Inst.
Address
MOVX Inst.
C4C3C2C1 C4C3C2C1
Figure 8-8: Data Memory Write with Stretch Value = 2
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 89 - Revision A4.0
9. POWER MANAGEMENT
The W79E22X SERIES provides idle mode and power-down mode to control power consumption.
These modes are discussed in the next two sections.
9.1 Idle Mode
The user can put the device into idle mode by writing 1 to the bit PCON.0. The instruction that sets the
idle bit is the last instruction that will be executed before the device goes into Idle Mode. In the Idle
mode, the clock to the CPU is halted, but not to the Interrupt, Timer, Watchdog timer, PWM, ADC and
Serial ports blocks. This forces the CPU state to be frozen; the Program counter, the Stack Pointer,
the Program Status Word, the Accumulator and the other registers hold their contents. The ALE and
PSEN pins are held high during the Idle state. The port pins hold the logical states they had at the time
Idle was activated. The Idle mode can be terminated in two ways. Since the interrupt controller is still
active, the activation of any enabled interrupt can wake up the processor. This will automatically clear
the Idle bit, terminate the Idle mode, and the Interrupt Service Routine (ISR) will be executed. After the
ISR, execution of the program will continue from the instru ction which put the device into Idle mode.
The Idle mode can also be exited by activating the reset. The device can be put into reset either by
applying a high on the external RST pin, a Power on reset condition or a Watchdog timer reset. The
external reset pin has to be held high for at least two machine cycles i.e. 8 clock periods to be
recognized as a valid reset. In the reset condition the program counter is reset to 0000h and all the
SFRs are set to the reset condition. Since the clock is already running there is no delay and execution
starts immediately. In the Idle mode, the Watchdog timer continues to run, and if enabled, a time-out
will cause a watchdog timer interrupt which will wake up the device. The software must reset the
Watchdog timer in order to preempt the reset which will occur after 512 clock periods of the time-out.
When the device is exiting from an Idle mode with a reset, the instruction following the one which put
the device into Idle mode is not executed. So there is no danger of unexpected writes.
9.2 Power Down Mode
The device can be put into Power Down mode by writing 1 to bit PCON.1. The instruction that does
this will be the last instruction to be executed before the device goes into Power Down mode. In the
Power Down mode, all the clocks are stopped and the device comes to a halt. All activity is completely
stopped and the power consumption is reduced to the lowest possible value. In this state the ALE and
PSEN pins are pulled low (if PWDNH=0). The port pins output the values held by their respective
SFRs.
The device will exit the Power Down mode with a reset or by an external interrupt pin enabled
(external interrupts 0 and 1). An external reset can be used to exit the Power down state. The high on
RST pin terminates the Power Down mode, and restarts the clock. The program execution will restart
from 0000h. In the Power down mode, the clock is stopped, so the Watchdog timer cannot be used to
provide the reset to exit Power down mode.
The device can be waken up from the Power Down mode by forcing an external interrupt pin
activation, provided the corresponding interrupt is enabled, while the global enable (EA) bit is set. If
these conditions are met, then either a low-level or a falling-edge at external interrupt pin will re-start
the oscillator. The device will then execute the interrupt service routine for the corresponding external
interrupt. After the interrupt service routine is completed, the program execution returns to the
instruction after one whi ch put the device into Power Down mode and continues from there.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 90 - Revision A4.0
MODE PROGRAM
MEMORY ALE PSEN PORT0 PORT1 PORT2 PORT3 PORT4 PORT5
Idle Internal 1 1 Data Data Data Data Data Data
Idle External 1 1 Float Data Address Data Data Data
Power
Down Internal 0 [1]
1 [2] 0 [1]
1 [2] Data Data Data Data Data Data
Power
Down External 0 [1]
1 [2] 0 [1]
1 [2] Float Data Data Data Data Data
Table 9-1: Status of external pins during Idle and Power Down
Note:
1. When PWDNH=0.
2. When PWDNH=1.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 91 - Revision A4.0
10. RESET CONDITIONS
The user has several hardware related options for placing the W79E22X SERIES into reset condition.
In general, most register bits go to their reset value irrespective of the reset condition, but there are a
few flags whose state depends on the source of reset. The user can use these flags to determine the
cause of reset using software. There are three ways of putting the device into reset state. They are
External reset, Power-On Reset and Watchdog reset. In general, most registers return to their default
values regardless of the source of the reset, but a couple flags depend on the source. As a result, the
user can use these flags to determine the cau se of th e reset.
The rest of this section discusse s the three ca us es of reset and then elaborates on the reset state.
10.1 Sources of reset
10.1.1 External Reset
The device samples the RST pin every machine cycle during state C4. The RST pin must be held high
for at least two machine cycles before the reset circuitry applies an internal reset signal. Thus, this
reset is a synchronous operation an d requires the clock to be running.
The device remains in the reset state as long as RST is one and remains there up to two machine
cycles after RST is deactivated. Then, the device begins program execution at 0000h. There are no
flags associated with the external reset, but, since the other two reset sources do have flags, the
external reset is the cause if those flags are cl ear.
10.1.2 Power-On Reset (POR)
If the power supply falls below Vrst, the device goes into the reset state. When the power supply
returns to proper levels, the device performs a power-on reset and sets the POR flag. The software
should clear the POR flag, or it will be difficult to determine the source of future resets.
10.1.3 Watchdog Timer Reset
The Watchdog Timer is a free-running timer with programmable time-out intervals. The program must
clear the Watchdog Timer before the time-out interval is reached to restart the count. If the time-out
interval is reached, an interrupt flag is set. 512 clocks later, if the Watchdog Reset is enabled and the
Watchdog Timer has not been cleared, the Watchdog Timer generates a reset. The reset condition is
maintained by the hardware for two machine cycles, and the WTRF bit in WDCON is set. Afterwards,
the device begins program execution at 0000h.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 92 - Revision A4.0
10.2 Reset State
When the device is reset, most registers return to their initial state. The Watchdog Timer is disabled if
the reset source was a power-on reset. The port registers are set to FFh, which puts most of the port
pins in a high state and makes Port 0 float (as it does not have on-chip pull-up resistors). The Program
Counter is set to 0000h, and the stack pointer is reset to 07h. After this, the device remains in the
reset state as long as the reset conditions are satisfied.
Reset does not affect the on-chip RAM, however, so RAM is preserved as long as VDD remains
above approximately 2 V, the minimum operating voltage for the RAM. If VDD falls below 2 V, the
RAM contents are also lost. In either case, the stack pointer is always reset, so the stack contents are
lost.
The WDCON SFR bits are set/cleared in reset condition depends on the source of the reset. The
WDCON SFR is set to a 0x0x0xx0b on an external reset. WTRF is set to a 1 on a Watchdog timer
reset, but to a 0 on power on/down resets. WTRF is not altered by an external reset. POR is set to 1
by a power-on reset. EWT is cleared to 0 on a Power-on reset and unaffected by other resets. All the
bits in this SFR have unrestricted read access. POR, WDIF, EWT and RWT bits require Timed Access
(TA) procedure to write. The remaining bits have unrestric ted write accesses. Please refer TA register
description. Table below lists the different reset values for WDCO N due to different sources of reset.
WDCON Watch-Dog
Control D8H (DF)
- (DE)
POR (DD)
- (DC)
- (DB)
WDIF (DA)
WTRF (D9)
EWT (D8)
RWT
x0xx 0000B External reset
x0xx 0100B Watchdog
reset
x1xx 0000B Power on
reset
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 93 - Revision A4.0
11. INTERRUPTS
The device has a four priority level interrupt structure with 20 interrupt sources. Each of the interrupt
sources has an individual priority bit, flag, interrupt vector and enable bit. In addition, all the interrupts
can be globally enabled o r disa bled.
11.1 Interrupt Sources
The External Interrupts INT0 and INT1 can be either edge triggered or level triggered, depending on
bits IT0 and IT1. The bits IE0 and IE1 in the TCON register are the flags which are checked to
generate the interrupt. In the edge triggered mode, the INTx inputs are sampled in every machine
cycle. If the sample is high in one cycle and low in the next, then a high to low transition is detected
and the interrupts request flag IEx in TCON is set. The flag bit requests the interrupt. Since the
external interrupts are sampled every machine cycle, they have to be held high or low for at least one
complete machine cycle. The IEx flag is automatically cleared when the service routine is called. If the
level triggered mode is selected, then the requesting source has to hold the pin low till the interrupt is
serviced. The IEx flag will not be cleared by the hardware on entering the service routine. If the
interrupt continues to be held low even after the service routine is completed, then the processor may
acknowledge another interrupt request from the same source. Note that the external interrupts INT2
are edge trigger only. By default, the individual interrupt flag corresponding to external interrupt 2 to 5
must be cleared manually by software. It can be configured with hardware cleared by setting the
corresponding bit HCx in T2MOD register. For instance, if HC2 is set hardware will clear IE2 flag after
program enters the interrupt 2 service routine. While for INT3 to INT5 can detect the rising, falling or
both edges which function are selectable by software located in INTCTRL [5:0] register. The Timer 0
and 1 Interrupts are generated by the TF0 and TF1 flags. These flags are set by the overflow in the
Timer 0 and Timer 1. The TF0 and TF1 flags are automatically cleared by the hardware when the
timer interrupt is serviced. The Timer 2 interrupt is generated by a logical OR of the TF2 and the EXF2
flags. These flags are set by overflow or capture/reload events in the timer 2 operation. The hardware
does not clear these flags when a timer 2 interrupt is executed. Software has to resolve the cause of
the interrupt between TF2 and EXF2 and clear the appropriate flag.
When ADC conversion is completed hardware will set flag ADCI to logic high to request ADC interrupt
if bit EADC (IE.6) is in high state. ADCI is cleared by software only .
The I2C function can generate interrupt, if EI2C and EA bits are enabled, when SI Flag is set due to a
new I2C status code is generated, SI flag is gen erated by hardware and must be cleared by software.
The Watchdog timer can be used as a system monito r or a simple timer. In either case, when the time-
out count is reached, the Watchdog timer interrupt flag WDIF (WDCON.3) is set. If the interrupt is
enabled by the enable bit EIE.4, then an interrupt will occur.
All the bits that generate interrupts can be set or reset by hardware, and thereby software initiated
interrupts can be generated. Each of the individual interrupts can be enabled or disabled by setting or
clearing a bit in the IE SFR. IE also has a global enable/disable bit EA, which can be cleared to
disable all interrupts.
11.2 Priority Level Structure
There are four priority levels for the interrupts; highest, high, low and lowest. The other interrupt
source can be individually set to either high or low levels. Naturally, a higher priority interrupt cannot
be interrupted by a lower priority interrupt. However there exists a predefined hierarchy amongst the
interrupts themselves. This hierarchy comes into play when the interrupt controller has to resolve
simultaneous requests having the same priority level. This hierarchy is defined as shown below; the
interrupts are numbered starting from the highest priority to the lowest.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 94 - Revision A4.0
SOURCE FLAG
VECTOR
ADDRESS FLAG CLEARED BY PRIORITY
LEVEL
External Interrupt 0 IE0 0003H Hardware, Follow the
inverse of pin 1(highest)
Timer 0 Overflow TF0 000BH Hardware, software 2
External Interrupt 1 IE1 0013H Hardware, Follow the
inverse of pin 3
Timer 1 Overflow TF1 001BH Hardware, software 4
Serial Port RI + TI 0023H Software 5
Timer 2 Overflow TF2 + EXF2 002BH Software 6
A/D Converter ADCI 0033H Software 7
I2C Channel I2C1 SI 003BH Software 8
Serial Port 1 RI_1 + TI_1 007BH Software 9
SPI interrupt SPIF + MODF +
SPIOVF 0083H Software 10
External Interrupt 2 IE2 0043H Hardware, software 11
External Interrupt 3 IE3 004BH Hardware, software 12
External Interrupt 4 IE4 0053H Hardware, software 13
External Interrupt 5 IE5 005BH Hardware, software 14
PWM Period PWMF 0073H Software 15
PWM Brake BKF 006BH Software 16
Timer 3 Overflow TF3 008BH Software 17
Capture
Input/Direction
Interrupt/QEI
CPTF0/QEIF+
CPTF1/DIRF+
CPTF2 0093H Software 18
NVM Interrupt NVMF 009BH Software 19
Watchdog Timer WDIF 0063H Software 20
Table 11- 1: Priority structure of interrupts
The interrupt flags are sampled every machine cycle. In the same machine cycle, the sampled
interrupts are polled and their priority is resolved. If certain conditions are met, the hardware will
execute an internally generated LCALL instruction which will vector the process to the appropriate
interrupt vector address. The co nditions for generating the LCALL are;
1. An interrupt of equal or higher priority is not currently being serviced.
2. The current polling cycle is the last machine cycle of the instruction currently being executed.
3. The current instruction does not involve a write to IE, EIE, EIE1, IP, EIP, EIP1, IPH, EIPH or EIP1H
registers and is not a RETI.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 95 - Revision A4.0
If any of these conditions are not met, then the LCALL will not be generated. The polling cycle is
repeated every machine cycle, with the interrupts sampled in the same machine cycle. If an interrupt
flag is active in one cycle but not responded to, and is not active when the above conditions are met,
the denied interrupt will not be serviced. This means that active interrupts are not remembered; every
polling cycle is new.
The processor responds to a valid interrupt by executing an LCALL instruction to the appropriate
service routine. This may or may not clear the flag which caused the interrupt. In case of Timer
interrupts, the TF0 or TF1 flags are cleared by hardware whenever the processor vectors to the
appropriate timer service routine. In case of external interrupt, INT0 and INT1, the flags are cleared
only if they are edge triggered. In case of Serial interrupts, the flags are not cleared by hardware. In
the case of Timer 2 interrupt, the flags are not cleared by hardware. The Watchdog timer interrupt flag
WDIF has to be cleared by software. The hardware LCALL behaves exactly like the software LCALL
instruction. This instruction saves the Program Counter contents onto the Stack, but does not save the
Program Status Word PSW. The PC is reloaded with the vector address of that interrupt which caus ed
the LCALL. These address of vector for the different sources are shown in Table 11- 1: Priority structure of
interrupts.
PRIORITY BITS
IPH/EIPH/EIP1H IP/EIP/EIP1
INTERRUPT PRIORITY LEVEL
0 0 Level 0 (lowest priority)
0 1 Level 1
1 0 Level 2
1 1 Level 3 (highest priority)
Table 11- 2: Four-level interrupt priority
Each interrupt source can be individually programmed to one of four priority levels by setting or
clearing bits in the IP, IPH, EIP, EIPH, EIP1 and EIP1H registers. An interrupt service routine in
progress can be interrupted by a higher priority interrupt, but not by another interrupt of the same or
lower priority. The highest priority interrupt service cannot be interrupted by any other interrupt source.
So, if two requests of different priority levels are received simultaneously, the request of higher priority
level is serviced.
If requests of the same priority level are received simultaneously, an internal polling sequence
determines which request is serviced. This is called the arbitration ranking. Note that the arbitration
ranking is only used to resolve simultaneous requests of the same priority level.
As below Table summarizes the interrupt sources, flag bits, vector addresses, enable bits, priority bits,
arbitration ranking, and whether each interrupt may wake up the CPU from Power Down mode.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 96 - Revision A4.0
SOURCE FLAG
VECTOR
ADDRESS
INTERRUPT
ENABLE BITS
INTERRUPT
PRIORITY
CONTROL BITS
ARBITRATION
RANKING
POWER
DOWN
WAKEUP
External Interrupt 0 IE0 0003H EX0 (IE.0) IPH.0, IP.0 1(highest) Yes
Timer 0 Overflow TF0 000BH ET0 (IE.1) IPH.1,IP.1 2 No
External Interrupt 1 IE1 0013H EX1 (IE.2) IPH.2,IP.2 3 Yes
Timer 1 Overflow TF1 001BH ET1 (IE.3) IPH.3,IP.3 4 No
Serial Port RI + TI 0023H ES (IE.4) IPH.4,IP.4 5 No
Timer 2 Overflow TF2 + EXF2 002BH ET2 (IE.5) IPH.5,IP.5 6 No
A/D Converter ADCI 003 3H EADC (IE.6) IPH.6,IP.6 7 No
I2C Channel I2C SI 003BH EI2C (EIE.0) EIPH.0, EIP.0 8 No
Serial Port 1 RI_1 + TI_1 007BH ES1 (EIE.7) EIPH.7, EIP.7 9 No
SPI interrupt SPIF/MODF/
SPIOVF 0083H ESPI (EIE1.0) EIP1H.0,
EIP1.0 10 No
External Interrupt 2 IE2 0043H EX2 (EIE.2) EIPH.2, EIP.2 11 No
External Interrupt 3 IE3 004BH EX3 (EIE.3) EIPH.3, EIP.3 12 No
External Interrupt 4 IE4 0053H EX4 (EIE.5) EIPH.5, EIP.5 13 No
External Interrupt 5 IE5 005BH EX5 (EIE.6) EIPH.6, EIP.6 14 No
PWM Period PWMF 0073H EPWM (EIE1.1) EIP1H.1,
EIP1.1 15 No
PWM Brake BKF 006BH EBK (EIE1.2) EIP1H.2,
EIP1.2 16 No
Timer 3 Overflow TF3 008B H ET3 (EIE1.3) EIP1H.3,
EIP1.3 17 No
Capture
Input/Direction
Interrupt/QEI
CPTF0/QEIF
+
CPTF1/DIRF
+ CPTF2
0093H ECPTF
(EIE1.4) EIP1H.4,
EIP1.4 18 No
NVM Interrupt NVMF 009BH ENVMI
(EIE1.5) EIP1H.5,
EIP1.5 19 No
Watchdog Timer WDIF 0063H EWDI (EIE.4) EIPH.4, EIP.4 20 No
Table 11- 3: Vector location for Interrupt sources and power down wakeup
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 97 - Revision A4.0
11.2.1 Response Time
The response time for each interrupt source depends on several factors like nature of the interrupt and
the instruction under progress. In the case of external interrupt INT0 to INT5, they are sampled at C3
of every machine cycle and then their corresponding interrupt flags IE0 and IE1 will be set or reset.
Similarly, the Serial port flags RI/RI_1 and TI/TI_1 are set in C4 of last machine cycle. The Timer 0
and 1 overflow flags are set at C3 of the machine cycle in which overflow has occurred. These flag
values are polled only in the next machine cycle. If a request is active and all three conditions are met,
then the hardware generated LCALL is executed. This call itself takes four machine cycles to be
completed. Thus there is a minimum time of five machine cycles between the interrupt flag being set
and the interrupt service routine being executed.
A longer response time should be anticipated if any of the three conditions are not met. If a higher or
equal priority is being serviced, then the interrupt latency time obviously depends on the nature of the
service routine currently being executed. If the polling cycle is not the last machine cycle of the
instruction being executed, then an additional delay is introduced. The maximum response time (if no
other interrupt is in service) occurs if the device is performing a write to IE, IP, IPH, EIE, EIP, EIPH,
EIE1, EIP1 or EIP1H and then executes a MUL or DIV instruction. From the time an interrupt source is
activated, the longest reaction time is 12 machine cycles. This includes 1 machine cycle to detect the
interrupt, 2 machine cycles to complete the IE, IP, IPH, EIE, EIP, EIPH, EIE1, EIP1 or EIP1H access,
5 machine cycles to complete the MUL or DIV instruction and 4 machine cycles to complete the
hardware LCALL to the interrupt vector location.
Thus in a single-interrupt system the interrupt response time will always be more than 5 machine
cycles and not more than 12 machine cycles. The maximum latency of 12 machine cycle is 48 clock
cycles. Note that in the standard 8051 the maximum latency is 8 machine cycles which equals 96
machine cycl es. This is a 50% reduction in terms of clock periods.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 98 - Revision A4.0
12. PROGRAMMABLE TIMERS/COUNTERS
The W79E22X SERIES has three 16-bit programmable timer/counters.
12.1 Timer/Counters 0 & 1
TM0 and TM1 are 16-bit Timer/Counters, and there are nearly identical. Each of these Timer/Counters
has two 8 bit registers which form the 16 bits counting register. For Timer/Counter 0, it consists of
TH0, the upper 8 bits register, and TL0, the lower 8 bit register. Similarly Timer/Counter 1 has two 8
bits registers; TH1 and TL1. The two timers can be configured to operate either as timers, counting
machine cycles or as counters counting external inputs.
When configured as a "Timer", the timer counts clock cycles. In "Counter" mode, the register is
incremented on the falling edge of the corresponding external input pins, T0 for Timer 0 and T1 for
Timer 1. The T0 and T1 inputs are sampled in every machine cycle at C4. If the sampled value is high
in one machine cycle and low in the next, then a valid high to low transition on the pin is recognized
and the count register is incremented. Since it takes two machine cycles to recognize a negative
transition on the pin, therefore the maximum counting rate is 1/8 of the master clock frequency. In both
"Timer" and "Counter" mode, the count register is updated at C3. Therefore, in the "Timer" mode, the
recognized negative transition on pin T0 and T1 can cause the count register value to be updated only
in the machine cycle following the one in which the negative edge was detected.
The "Timer" or "Counter" function is selected by the " TC/ " bit in the TMOD Special Function Register.
Each Timer/Counter has one selection bit for its own; bit 2 of TMOD selects the function for
Timer/Counter 0 and bit 6 of TMOD selects the function for Timer/Counter 1. In addition each
Timer/Counter can be set to operate in any one of four possible modes. The mode selection is done
by bits M0 and M1 in the TMOD SFR.
12.1.1 Time-Base Selection
The W79E22X SERIES can operate like the standard 8051/52 family, counting at the rate of 1/12 of
the clock speed, or in turbo mode, counting at the rate of 1/4 clock speed. The speed is controlled by
the T0M and T1M bits in CKCON, and the default value is zero, which uses the standard 8051/52
speed.
12.1.2 Mode 0
In Mode 0, the timer/counter is a 13-bit counter. The 13-bit counter consists of THx (8 MSB) and the
five lower bits of TLx (5 LSB). The upper three bits of TLx are ignored. The timer/counter is enabled
when TRx is set and either GATE is 0 or INT
x
is 1. When TC/ is 0, the timer/counter counts clock
cycles; when TC/ is 1, it counts falling edges on T0 (P3.4 for Timer 0) or T1 (P3.5 for Timer 1). For
clock cycles, the time base may be 1/12 or 1/4 clock speed, and the falling edge of the clock
increments the counter. When the 13-bit value moves from 1FFFh to 0000h, the timer overflow flag
TFx is set, and an interrupt occurs if enabled. This is illustrated in next figure below.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 99 - Revision A4.0
12.1.3 Mode 1
Mode 1 is the same as Mode 0, except that the timer/counter is 16 bits, instead of 13 bits.
Figure 12-1: Timer/Counters 0 & 1 in Mode 0 and Mode 1
12.1.4 Mode 2
In Mode 2, the timer/counter is in the Auto Reload Mode. In this mode, TLx acts as an 8 bits count
register, while THx holds the reload value. When the TLx register overflows from FFh to 00h, the TFx
bit in TCON is set and TLx is reloaded with the contents of THx, and the counting process continues.
The reload operation leaves the contents of the THx register unchanged. Counting is enabled by the
TRx bit and proper setting of GATE and INT
x
pins. As in the other two modes 0 and 1, mode 2 allows
counting of either clock cycles (clock/12 or clock/4) or pulses on pin Tn.
Figure 12-2: Timer/Counter 0 & 1 in Mode 2
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 100 - Revision A4.0
12.1.5 Mode 3
Mode 3 is used when an extra 8-bit timer is needed. It has different effect on Timer 0 and Timer 1. TL0
and TH0 become two separate 8 bits counters. TL0 uses the Timer 0 control bits TC/ , GATE, TR0,
INT0 and TF0, and it can be used to count clock cycles (clock/12 or clock/4) or falling edges on pin
T0, as determined by TC/ (TMOD.2). TH0 becomes a clock-cycle counter (clock/12 or clock/4) and
takes over the Timer 1 enable bit TR1 and over flow flag TF1. In contrast, mode 3 simply freezes Timer
1. If Timer 0 is in mode 3, Timer 1 can still be used in modes 0, 1 and 2, but it no longer has control
over TR1 and TF1. Therefore when Timer 0 is in Mode 3, Timer 1 can only count oscillator cycles, and
it does not have an interrupt or flag. With these limitations, baud rate generation is its most practical
application, but other time-base functions may be achieved by reading the regi sters.
Figure 12-3: Timer/Counter Mode 3
12.2 Timer/Counter 2
Timer/Counter 2 is a 16-bit up/down-counter equipped with a capture/reload capability. The clock
source for Timer/Counter 2 may be the external T2 pin ( T2C/ = 1) or the crystal oscillator ( T2C/ = 0),
divided by 12 or 4. The clock is enabled and disabled by TR2. Timer/Counter 2 runs in one of four
operating modes, each of which is di scussed below.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 101 - Revision A4.0
12.2.1 Capture Mode
Capture mode is enabled by setting RL2CP/ in T2CON to 1. In capture mode, Timer/Counter 2 is a
16-bit up-counter. When the counter rolls over from FFFFh to 0000h, the timer overflow flag TF2 is
set, and an interrupt is generated, if enabled.
If the EXEN2 bit is set, a negative transition on the T2EX pin captures the current value of TL2 and
TH2 in the RCAP2L and RCAP2H registers. It also sets the EXF2 bit in T2CON, which generates an
interrupt if enabled. In addition, if the T2CR bit in T2MOD is set, the W79E22X SERIES resets Timer 2
automatically after each capture. This is illustrated below.
(RCLK,TCLK, RL2CP/ )= (0,0,1)
Figure 12-4: Timer2 16-Bit Capture Mode
12.2.2 Auto-reload Mode, Counting up
This mode is enabled by clearing RL2CP/ in T2CON register and DCEN in T2MOD. In this mode,
Timer/Counter 2 is a 16-bit up-counter. When the counter rolls over from FFFFh to 0000h, the timer
overflow flag TF2 is set, and TL2 and TH2 capture the contents of RCAP2L and RCAP2H,
respectively. Alternatively, if EXEN2 is set, a negative transition on the T2EX pin causes a reload,
which also sets the EXF2 bit in T2CON.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 102 - Revision A4.0
(RCLK,TCLK, RL2CP/ )= (0,0,0) & DCEN= 0
Figure 12-5: 16-Bit Auto-reload Mode, Counting Up
12.2.3 Auto-reload Mode, Counting Up/Down
This mode is enabled by clearing CP RL/2 in T2CON and setting DCEN in T2MOD. In this mode,
Timer/Counter 2 is a 16-bit up/down-counter, whose direction is controlled by the T2EX pin (1 = up, 0
= down). If Timer/Counter 2 is counting up, an overflow reloads TL2 and TH2 with the contents of the
capture registers RCAP2L and RCAP2H. If Timer/Counter 2 is counting down, TL2 and TH2 are
loaded with FFFFh when the contents of Timer/Counter 2 equal the capture registers RCAP2L and
RCAP2H. Regardless of direction, reloading sets the TF2 bit. It also toggles the EXF2 bit, but the
EXF2 bit can not generate an interrupt in this mode. This is illu strated below.
(RCLK,TCLK, RL2CP/ )= (0,0,0) & DCEN= 1
Figure 12-6: 16-Bit Auto-reload Up/Down Counter
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 103 - Revision A4.0
12.2.4 Baud Rate Generator Mode
Baud rate generator mode is enabled by setting either RCLK or TCLK in T2CON. In baud rate
generator mode, Timer/Counter 2 is a 16-bit counter with auto-reload when the count rolls over from
FFFFh. However, rolling-over does not set TF2. If EXEN2 is set, then a negative transition on the
T2EX pin sets EXF2 bit in the T2CON register and causes an interrupt request.
RCLK+TCLK=1, RL2CP/ =0
Figure 12-7: Baud Rate Generator Mode
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 104 - Revision A4.0
13. WATCHDOG TIMER
The Watchdog Timer is a free-running timer that can be programmed to serve as a system monitor, a
time-base generator or an event timer. It is basically a set of dividers that divide the system clock to
determine the time-out interval. When the time-out occurs, a flag is set, which can generate an
interrupt or a system reset, if enabled. The interrupt will occur if its interrupt and global interrupt
enables are set. The interrupt and reset functions are independent of each other and may be used
separately or together.
The main use of the Watchdog Timer is as a system monitor. In case of power glitches or
electromagnetic interference, the processor may begin to execute errant code. The Watchdog Timer
helps W79E22X SERIES recovers from these states. During development, the code is first written
without the watchdog interrupt or reset. Then, the watchdog interrupt is enabled to identify code
locations where the interrupt occurs, and instructions are inserted to reset the Watchdog Timer in
these locations. In the final version, the watchdog interrupt is disabled, and the watchdog reset is
enabled. If errant code is executed, the Watchdog Timer is not reset at the required times, so a
Watchdog Timer reset oc c urs.
When used as a simple timer, the reset and interrupt functions are disabled. The Watchdog Timer can
be started by RWT and sets the WDIF flag after the selected time interval. Meanwhile, the program
polls the WDIF flag to find out when the selected time interval has passed. Alternatively, the Watchdog
Timer can also be used as a very long timer. In this case, the interrupt feature is enabled.
Figure 13-1: Watchdog Timer
The Watchdog Timer should be started by RWT because this ensures that the timer starts from a
known state. The RWT bit is self-clearing; i.e., after writing a 1 to this bit, the bit is automatically
cleared. After setting RWT, the Watchdog Timer begins counting clock cycles. The time-out interval is
selected by WD1 and WD0 (CK CON.7 and CKCON.6).
WD1 WD0
INTERRUPT
TIME-OUT
RESET
TIME-OUT
NUMBER OF
CLOCKS
TIME
@ 10 MHZ
TIME
@ 11.0592 MHZ
TIME
@ 25 MHZ
0 0 217 217 + 512 131072 13.11 mS 11.85 mS 5.24 mS
0 1 220 220 + 512 1048576 104.86 mS 94.81 mS 41.94 mS
1 0 223 223 + 512 8388608 838.86 mS 758.52 mS 335.54 mS
1 1 226 226 + 512 67108864 6710.89 mS 6068.15 mS 2684.35 mS
Table 13-1: Time-out values for the Watchdog Timer
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 105 - Revision A4.0
When the selected time-out occurs, the watchdog interrupt flag WDIF (WDCON.3) is set. After
watchdog time-out, and if Watchdog Timer Reset EWT (WDCON.1) is enabled, the Watchdog Timer
will cause a reset 512 clocks later. This reset lasts two machine cycles, and the Watchdog Timer reset
flag WTRF (WDCON.2) is set, which indicates that the Watchdog Timer caused the reset. RWT can
be used to clear Watchdog timer before a time-out occurs.
The Watchdog Timer is disabled by a power-on/fail reset. The external reset and Watchdog Timer
reset can not disable Watchdog Timer, instead it only resta rt the Timer.
The control bits that support the Watchd og Timer are described as belo w:
Watchdog Timer Control (WDCON)
BIT NAME FUNCTION
7 -
Reserved.
6 POR
Power-on reset flag. The hardware sets this flag during power–up, and it can only
be cleared by software. This flag can also be written b y software.
5-4 -
Reserved.
3 WDIF
Watchdog Timer Interrupt Flag. If the watchdog interrupt is enabled, the hardware
sets this bit to indicate that the watchdog interrupt has occurred. If the interrupt is
not enabled, this bit indicates that the time-out period has elapsed. This bit must be
cleared by software.
2 WTRF
Watchdog Timer Reset Flag. If EWT is 0, the Watchdog Timer has no affect on this
bit. Otherwise, the hardware sets this bit when the Watchdog Timer causes a reset.
It can be cleared by software or a power-fail reset. It can be also read by software,
which helps determine the cause of a reset.
1 EWT
Enable Watchdog-Timer Reset. Set this bit to enable the Watchdog Timer Reset
function.
0 RWT
Reset Watchdog Timer. Set this bit to reset the Watchdog Timer before a time-out
occurs. This bit is automatically cleared by the hard w are.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 106 - Revision A4.0
The POR, EWT, WDIF and RWT bits are protected by the Timed Access procedure. This procedure
prevents software, especially errant code, from accidentally enabling or disabling the Watchdog Timer.
An example is provided below.
org 63h
mov TA,#AAH
mov TA,#55H
clr WDIF
jnb execute_reset_flag,bypass_reset ; Test if CPU need to reset.
jmp $ ; Wait to reset
bypass_reset:
mov TA,#AAH
mov TA,#55H
setb RWT
reti
org 300h
start:
mov ckcon,#01h ; Select 2 ^ 17 timer
; mov ckcon,#61h ; Select 2 ^ 20 timer
; mov ckcon,#81h ; Select 2 ^ 23 timer
; mov ckcon,#c1h ; Select 2 ^ 26 timer
mov TA,#aah
mov TA,#55h
mov WDCON,#00000011B
setb EWDI
setb ea
jmp $ ; Wait time out
Clock Control
WD1, WD0: CKCON.7, CKCON.6 - Watchdog Timer Mode select bits. These two bits select the time-
out interval for the Watchdog Timer. The reset interval is 512 clocks longer than the selected interval.
The default time-out is 217 clocks, the shortest time-out period.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 107 - Revision A4.0
14. PULSE-WIDTH-MODULATED (PWM) OUTPUTS
14.1 PWM Features
The PWM block sup ports the following features;
z Four 12-bit PWM channels or complementary pairs:
4 independent PWM outputs: PWM0, PWM2, PWM 4 & PWM6.
4 complementary PWM pairs with insertion of programmable dead-time:
(PWM0,PWM1), (PWM2,PWM3 ), (PWM4,PWM5), (PWM6,PWM7)
z Three operation mode:
Edge aligned mode, Center aligned mod e and Single shot mode.
z Programmable dead-time insertion between paired PWMs.
z Output override control for Electri cally Commutated M otor operation.
z Hardware/software brake protection.
z Support 2 independent interru pts:
Interrupt request when up/down counter comparison matche d or underflow.
Interrupt request when external b ra ke asserted.
z Flexible operation in debug mode.
z High Source/Sink current.
The outputs for PWM0 to PWM7 are on P2[5:0] (PWM[5:0]) and P5[1:0] (PWM [7:6]) respectively.
After CPU reset, the internal output of each PWM channel depends on the output controls and polarity
settings. The interval between successive outputs is controlled by a 12–bit up/down counter which
uses the oscillator frequency with configurable internal clock prescaler as its input. The PWM counter
clock, has the frequency as the clock source FPWM = FOSC/Prescaler. The following Figure 14-1: PWM Block
Diagram below is the block diagram for PWM.
Figure 14-1: PWM Block Diagram
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 108 - Revision A4.0
14.2 PWM Control Registers
The overall functioning of the PWM module is controlled by the contents of the PWMCON1 register.
The operation of most of the control bits is straightforward. For example PWM0I is an invert bit for
each output which causes results in the output to have the opposite value compared to its non-
inverted output. The transfer of the data from the Counter and Compare registers to the control
registers is controlled by the PWMCON1.6 (load) while PWMCON1.7 (PWMRUN) allows the PWM to
be either in the run or idle state.
If the Brake pin is not used to control the brake function, the “Brake when PWM is not running”
function can be used to cause the outputs to have a given state when the PWM is halted. This
approach should be used only in time critical situations when there is not sufficient time to use the
approach outlined above, since going from the Brake state to run without causing an undefined state
on the outputs is not straightforward. A discussion on this topic is included in the section on
PWMCON2.
The Brake function, which is controlled by the contents of the PWMCON2 register, is somewhat
unique. In general, when Brake is asserted, the eight PWM outputs are forced to a user select ed state,
namely the state selected by PWMCON3. As shown in the description of the operation of the
PWMCON2 register, if PWMCON2.4, BKEN, is a “1” brake is asserted under the control
PWMCON2.7, BKCH, and PWMCON2.5, BPEN. As shown, if both are a “0”, brake is asserted. If
PWMCON2.7 is a “1”, brake is asserted when the PWMRUN bit, PWMCON1.7, is a “0”. If
PWMCON2.6, BKPS, is a “1”, brake is asserted when the Brake Pin, P1.1, has the same polarity as
PWMCON2.6. When brake is asserted in response to this pin, the PWMRUN bit in PWMCON1.7 is
automatically cleared, and BKF (PWMCON4.0) flag will be set. When both BKCH and BPEN are “1”,
BKF will be set when Brake pin is asserted, but PWM generator continues to run. With this special
condition, the PWM output does not follow PWMnB, instead it output continuously as per normal
without affected by the brake.
Since the Brake Pin being asserted will automatically clear the PWMRUN (PWMCON1.7) and BKF
(PWMCON4.0) flag will be set, the user program can poll this bit or enable PWM’s brake interrupt to
determine when the Brake Pin causes a brake to occur. The other method for detecting a brake
caused by the Brake Pin would be to tie the Brake Pin to one of the external interrupt pins. This latter
approach is needed if the Brake signal is of insufficient length to ensure that it can be captured by a
polling routine. When, after being asserted, the condition causing the brake is removed, the PWM
outputs go to whatever state that had immediately prior to the brake. This means that in order to go
from brake being asserted to having the PWM run without going through an indeterminate state, care
must be taken. If the Brake Pin causes brake to be asserted, the following prototype code will allow
the PWM to go from brake to run smoothly by software polling BKF flag or enable PWM’s interrupt.
• Rewrite PWMCON2 to change fro m Brake Pin enabled to S/W Brake.
• Write PWM (0, 2, 4, 6) Compare register to always “1”, FFFh, or always “0”, 000h, to initialize PWM
output to a High or Low, respectively.
• Clear BKF flag.
• Set PWMCON1 to enable PWMRUN and Load.
• Poll Brake Pin until it is no longer active.
• Poll PWMCON1 to find that Load Bit PWMCON1.6 is “0”. When “0”:
• Write PWMP (0, 2, 4, and 6) Counter register for desired pulse widths and counter reload values.
• Set PWMCON1 to Run and Transfer.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 109 - Revision A4.0
Note that if a narrow pulse on the Brake Pin causes brake to be asserted, it may not be possible to go
through the above code before the end of the pulse. In this case, in addition to the code shown, an
external latch on the Brake Pin may be required to ensure that there is a smooth transition in going
from brake to run. A compare value greater than the counter reloaded value resulted in the PWM
output being high. In addition there are two special cases. A compare value of all zeroes, 000H,
causes the output to remain permanently Low. A compare value of all ones, FFFH, results in the PWM
output remaining permanently High.
Figure 14-2: PWM Time-base Generator and Brake Function
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 110 - Revision A4.0
The PWMP register fact that writes are not into the Counter register that controls the counter; rather
they are into a holding register. As described below the transfer of data from this holding register, into
the register which contains the actual reload value, is controlled by the user’s program. The width of
each PWM output pulse is determined by the value in the appropriate compare register. Each PWM
register pair of (PWMPH,PWMPL), (PWM0H,PWM0L), (PWM2H,PWM2L), (PWM4H,PWM4L) and
(PWM6H,PWM6L),in the format of 12-bit width by combining 4 LSB of high byte and 8 MSB bits of low
byte, decides the PWM period and each channel’s duty cycle. The following equations show the
formula for period and duty for each p wm operation mode:
Edge aligned:
Period = (pwmp +1) * ioclock period * 1/prescaler
Duty = duty * ioclock period
Single shot:
Period = (pwmp) * ioclock period /prescale r (no meaning since it is not periodic)
Duty = (duty) * ioclock peri od/prescaler (for prescaler 1, 1/2/2, 1/4)
(duty-1) * ioclock period /prescaler < Duty < (duty) * ioclock period/prescaler (for prescaler 1/16)
Centre aligned:
Period = (pwmp* 2) * ioclock period /prescaler
Duty = (duty*2 - 1) * ioclock period /prescaler
Note: “duty” refers to PWM0~3 register value.
14.3 PWM Pin Structures
As show in the following diagrams, PWM pin structures are controllable through PWM options bits
(PWMEE/PWMOE) and SFR PWMCON4 bits (PWMEOM/PWMOO M /PWM6OM/PWM7OM).
PWMEE/PWMOE
(OPTION BITS) PWMEOM/PWMOOM
/PWM6OM/PWM7OM
PIO.X
(X = 0-7)
PIN STRUCTURES
X 0 X Tri-state
1 (Disable) 1 X Quasi (I/O output)
0 (Enable) 1 0 Push Pull (PWM output)
0 (Enable) 1 1 Push Pull (I/O output)
Table 14-1: PWM pin structures (during internal rom execution)
PWMEE/PWMOE
(OPTION BITS)
PWMEOM/PWMOOM
/PWM6OM/PWM7OM
PIO.X
(X = 0-7)
PIN
OUTPUT PIN STRUCTURES
1 (Disable) X X External
access Push Pull
0 (Enable) X X
External
access Push Pull (strong)
Table 14-2: PWM pin structures (during external rom execution)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 111 - Revision A4.0
Note: PWMEOM/PWMOOM/PWM6OM/PWM7OM are cleared to zero when CPU in reset state.
Thus, the port pins that multi-function with PWM will be tri-stated on default. User is required
to set the bits to enable GPIO/PWM outputs.
Figure 14-3: PWM0, 2 & 4 I/O pins
Figure 14-4: PWM1, 3 & 5 I/O pins
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 112 - Revision A4.0
Figure 14-5: PWM6 I/O pin
Figure 14-6: PWM7 I/O pin
Figure 14-7: Even PWM Output
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 113 - Revision A4.0
PWM Output (PWM1,3,5,7)
OPOL (Option Bit)
PWM Initial State
0
1
0
1
0
1
Low
High
PWMoB
PWMoEN
In Brake Condition
C
Note: o = 1,3,5,7
Figure 14-8: Odd PWM Output
14.4 Complementary PWM with Dead-time and Override functions
In this module there are four duty-cycle generators, from 0 through 3. The total of eight PWM output
pins in this module, from 0 through 7. The eight PWM outputs are grouped into output pairs of even
and odd numbered outputs. In complimentary modes, the odd PWM pins must always be the
complement of the corresponding even PWM pin. For example, PWM1 will be the complement of
PWM0. PWM3 will be the complement of PWM2, PWM5 will be the complement of PWM4 and PWM7
will be the complement of PWM6. Complementary mode is enabled only when both PWMeEN and the
corresponding PWMoEN are set to high. The time base for the PWM module is provided by its own
12-bit timer, which also incorporates selectable prescaler options.
Note: PWM pairs of (PWM2, 3), (PWM4, 5) and (PWM6, 7) are in the same structure as pair of
(PWM0, 1). (Refer to Figure 14-9).
Figure 14-9: Complementary PWM with Dead-time and Override functions
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 114 - Revision A4.0
14.5 Dead-Time Insertion
The dead time generator inserts an “off” period called “dead time” between the turnings off of one pin
to the turning on of the complementary pin of the paired pins. This is to prevent damage to the power
switching devices that will be connected to the PWM output pins. Each complementary output pair for
the PWM module has 6-bits counter used to produce the dead time insertion. Each dead time unit has
a rising and falling edge detector connected to the duty cycle comparison output. The dead time is
loaded into the timer on the detected PWM edge event. Depending on whether the edge is rising or
falling, one of the transitions on the complementary outputs is delayed until the timer counts down to
zero. A timing diagram indicating the dead time insertion for one pair of PWM outputs is shown in
Figure 14-10 and Figure 14-11.
PWM0 without
Dead-Time
PWM1 without
Dead-Time
PWM0 with
Dead-Time
PWM1 with
Dead-Time
Dead-Time Interval
Note: PDTC0.4 selects insertion at rising edge
Figure 14-10: Effect of Dead-Time for complementary pairs (rising edge)
PWM0 without
Dead-Time
PWM1 without
Dead-Time
PWM0 with
Dead-Time
PWM1 with
Dead-Time
Dead-Time Interval
Note: PDTC0.4 selects insertion at falling edge
Figure 14-11: Effect of Dead-Time for complementary pairs (falling edge)
Note: User need to take care that power switches should not be use when PWM pair is
asserted (high) at the same time.
PDTCO and PDTC1 have time access protection in writing access. In Power inverter application,
a dead time insertion avoids the upper and lower switches of the half bridge from being active at the
same time. Hence the dead time control is crucial to proper operation of a system. Some amount of
time must be provided between turning off of one PWM output in a complementary pair and turning on
the other transistor as the power output devices cannot switch inst antaneously.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 115 - Revision A4.0
14.6 PWM Output Override
Figure 14-12: Override Flow Diagram
Each of the PWM output channels can be manually overridden by using the appropriate bits in the
POVD and POVM registers. This function allow user to drive the PWM I/O pins to specified logic
states independent of the duty cycle comparison units. The PWM override bits are useful when
controlling various types of Electrically Commutated Motor (ECM) like a BLDC motor. The POVD
register contains eight bits, POVD[7:0]. It determines which PWM I/O pins will be overridden. On reset,
POVD is 00H.
The POVM register contains eight bits, POVM[7:0]. It determines the state of the PWM I/O pins when
a particular output is overridden via the POVD bits. On reset, POVM is 00H. The POVM[7:0] bits are
active-high. When the POVM[7:0] bits are set, the corresponding POVD[7:0] bit will have effect on the
PWM output. When one of the POVM bits is set, the output on the corresponding PWM I/O pin will be
determined by the state of corresponding POVD bit. When a POVM bit is clear, the PWM pin will be
driven to its active state. The odd channel is always the complement of the even channel with dead
time inserted.. Figure 14-13 demonstrates the override function in complementary mode.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 116 - Revision A4.0
Figure 14-13: Override bit in complementary mode
Assume rising edge d ead time insertion; refer to Figure 14-12: Override Flow Diagram.
Example: POVM0 = 1 and POVM1 = 0; PWM0EN and PWM1E N = 1;
a. Odd override bits have no effect in complementary mode.
b. Even override bit is activated, which causes the Odd PWM to deactivate.
c. Dead-Time insertion.
d. Even PWM activated after the dead-time.
e. Even override bit is deactivated, which causes the Even PWM to deactivate.
f. Dead-Time insertion.
g. Odd PWM is activated after the dead time.
Figure 14-14: Example 1 of Output Even & Odd Override
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 117 - Revision A4.0
STATE
POVM
PWMEEN = 1
PWMOEN = 1
POVD
1 1111 1111b 0110 0100b
2 1111 1111b 1010 0001b
3 1111 1111b 0000 1001b
4 1111 1111b 0001 1000b
5 1111 1111b 1001 0010b
6 1111 1111b 0100 0110b
Table 14-3: Example 1 of Output Even & Odd Override
Figure 14-15: Example 2 of Output Override
State
#1: POVM
(Odd not overridenot in
complementary)
(PWMeEN = 1,
PWMoEN = 0)
#2: POVM
(Odd not Override in
complementary)
(PWMeEN = 1,
PWMoEN = 1)
#3: POVM
(Odd with Override
not in
complementary)
(PWMeEN = 1,
PWMoEN = 1)
POVD
1 0001 0100b 0001 0100b 1011 1110 0000 0000b
2 0000 0101b 0000 0101b 1010 1111 0000 0000b
3 0100 0001b 0100 0001b 1110 1011 0000 0000b
4 0101 0000b 0101 0000b 1111 1010 0000 0000b
Table 14-4: Example 2 of Output Override
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 118 - Revision A4.0
14.7 Edge Aligned PWM (up-counter)
Figure 14-16: Edge-Aligned PWM
In edge-aligned PWM Output mode, the 12 bits counter will starts counting from 0 to match with the
value of the duty cycle PWM0 (old). When the match occurs, it will toggle the PWM0 output waveform
to low. After CPU resets, the value of PWM0 waveform at starts of counter depend on the polarity
setting located in the Option bits. At this point a new PWM0 (new) is written. The counter will continue
counting to match with the value of the period register, PWMP (old) and toggle the PWM0 waveform to
high. Please take note that PWM0 and PWMP is a double-buffered register used to set the duty cycle
and counting period for the PWM time base respectively. For the 1st buffer it is accessible by user
while the 2nd buffer holds the actual compare value used in the present period. Load bit must be set to
1 to enable the value to be loaded in to the 2nd buffer register when cou nter underflow/match.
When the counter matches the PWMP (old) it will automatically update the new duty cycle register and
the counter will again starts counting upwards to match the value PWM0 (new). At this point it will
toggle the PWM0 waveform to low. New PWMP is written at this point. When the counter continues
counting to match the PWMP (old), again the PWM0 waveform will be toggle to high. The counter
starts counting from 0 again; at this point the value is PWM0 (new ) and PWMP (new) to be match by
the counter and once the counter match es the se valu es it will be toggle at the PWM output.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 119 - Revision A4.0
Set PMOD[1:0] = 00
Start : Load = 1
PWMRUN = 1, CLRPWM = 1
Load PWMn and PWMP to working registers
“Load” auto clear by hardware (h/w)
PWMnI = 1?
(output inverted?)
PWMn output : Inverted
0 if counter < PWMn
1 if counter > PWMn
PWMn output : Non Inverted
1 if counter < PWMn
0 if counter > PWMn
Counter counting up
Counter = PWMn?
PWMn output toggle
Counter continues counting up
Counter = PWMP?
PWMn output toggle
Reset counter to zero (h/w)
PWMF flag set
Load = 1?
Load new PWMP/PWMn value
to working register
No Yes
No
No
No
Yes
Figure 14-17: Edge-Aligned Flow Diagram
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 120 - Revision A4.0
Figure 14-18: Program Flow for Edge-Aligned mode
PWMP (7FF)
PWM0 (3FF)
PWM0
Waveform
PWM Period PWM Period PWM Period PWM Period PWM Period
Figure 14-19: PWM0 Edge Aligned Waveform Output
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 121 - Revision A4.0
14.8 Center Aligned PWM (up/down counter)
PWM0 (old)
PWM0 (new)
PWMP (old)
PWMP (new)
PWM0
waveform
PWM periodPWM period
New PWM0
is written
New PWMP
is written
1. 12-bit up counter matches PWMP
2. Update new duty cycle register (PWM0,2,4 and 6) if Load=1
3. Update new PWM period register (PWMP) if Load=1
Figure 14-20: Center-Aligned Mode
Center-aligned PWM signals are produced by the module when the PWM time base is configured in
an Up/Down Counting mode (see Figure 14-20). The counter will start counting-up from 0 to match the
value of PWM0 (old); this will cause the toggling of the PWM0 output to low. The CPU reset states
determine the starts value of PWM0 waveform at starts of counter lies on the polarity setting located in
the Option bits. At this time the new PWM0 is written to the register. Counter continue to count and
match with the PWMP (old). Upon reaching this states counter is configured automatically to down
counting and toggle the PWM0 output when counter matches the PWM0 (old) value. Interrupt request
when up/down counter underflow. Once the counter reaches 0 it will update the duty cycle register
with Load = 1. Up-counting is continues with the matching at PWM0 (new) follow by a low toggle at the
PWM0 output. By this time the PWMP buffer is still consist of the PWMP (old) value. A new PWMP is
written. So the counter will still matches with this value and continues with down counting and
matched the PWM0 (new) and toggle the PWM0 output.
Again updates on the PWM period register is reflected on the 3rd cycle of the diagram by starts
counting from 0 to match the PWM0 (new) and toggle at the PWM0 output to low. Counter is
continuing up-counting, upon reaching the PWMP (new) it is matched. Then counter is down counting
automatically to match at the PWM0 (new) to get a toggle high at PWM0 output.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 122 - Revision A4.0
Figure 14-21: Center-aligned Flow Diagram
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 123 - Revision A4.0
Figure 14-22: PWM0 Center Aligned Waveform Output
14.9 Single Shot (Up-Counter)
Figure 14-23: Single Shot Mode
The single shot mode PWM module will produce single pulse output. Single-pulse operation is
configured when the PMOD1:PMOD0 bits are set to ‘01’ in PWMCON3 register. This mode of
operation is useful for driving certain types of ECMs. In this mode, the PWM counter will start counting
upwards when the PWMRUN is set to 1. When the counter value matches with the PWMP register,
PWM interrupt will be generated if it is enable and PWMF is set and counter will reset to zero on the
following input clock edge and PWMRUN will be cleared by hardware. Duty cycle of PWM channels
are determined by the respective PWMx registers, where x = 0,2,4,6
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 124 - Revision A4.0
Example Steps of setting up Single Shot:-
1. Set initial state = 0 (controlled by EPOL option bit)
2. PWM0EN=0, POVM.0=0, PWM0I=0, PWM0=0000H(for keep comparator output in low state),
PWMP=0001H(let the period as short as possible)
3. PWMRUN=1(Do a dummy PWMRUN for loading PWM0 to compare register0, which make
comparator output LOW always.
4. PWM0EN=1, now the PWM0 pin should be still in 0 state.
5. PWMP=xxxxH(controls a period), PWM0=yyyyH(controls duty or pulse width)
6. PWMRUN=1(this time a real PWM single shot signal user wanted. The wave form should be the
upper one.
Note: In single shot mode, it’s important that user sets CLRPWM together with PWMRUN and
LOAD in order to have PWMn and PWMP loaded into working registers immediately.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 125 - Revision A4.0
Figure 14-24: Single-Shot Flow Diagram
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 126 - Revision A4.0
14.10 Smart Fault Detector
This is a brake detection logic that is new to support external brake conditions that already exist. A
dedicated SFR FSPLT is added for this function. The SFR consists of smart fault detector control and
status bits. It basically consists of a clock divider, 8 bits counter, comparator and 4 selectable compare
values. The following diagram show the gene ral block diagram.
Figure 14-25: Smart Fault Detector
The smart fault detector is enabled when bit LSBD = 1 (FSPLT.0). This logic detects low level brake
pin. The 8 bits counter is enabled by SFCEN bit located in SFR FSPLT.3. The counter is clock by
Fosc divider selectable by SFP1-0 control bits (FSPLT.5-4). The comparator compares the 8 bits
counter value with the compare valu e selectable with SCMP1-0 (FSPLT1-0 ).
Upon initial detection of low level at brake pin, the 8 bits counter will be active. This will cause the
counter to increment. While the counter is active and there is high level detected at brake pin, the
counter will decrement. See next figure for timing diagram. When the counter value reaches compare
value, BKF will be asserted.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 127 - Revision A4.0
Figure 14-26: Smart Fault Detector timing diagram
The smart fault detector consists of 2 status bits; SFCST and SFCDIR. A SFCST show status of 8 bits
counter is active or in-active, while SFCDIR show s the counter’s counting direction. When SFCST = 0,
SFCDIR keeps its’ state.
The s/w can manually disable and clear the 8 bits cou nter, by clea ring SFCEN to 0.
The following tables show the tabulate accumulated low level Brake time with various Fosc/x dividers
and compares value, at 40MHz and 20MHz.
FOSC/X 1/4 1/8 1/16 1/128
SCMP[1:0] 10,000,000 5,000,000 2,500,000 312,500
4 0.40us 0.80us 1.60us 12.80us
16 1.60us 3.20us 6.40us 51.20us
64 6.40us 12.80us 25.60us 204.80us
128 12.80us 25.60us 51.20us 409.60us
Table 14-5: Example the accumulated low level time at 40 MHz
FOSC/X 1/4 1/8 1/16 1/128
SCMP[1:0] 5,000,000 2,500,000 1,250,000 156,250
4 0.80us 1.60us 3.20us 25.60us
16 3.20us 6.40us 12.80us 102.40us
64 12.80us 25.60us 51.20us 409.60us
128 25.60us 51.20us 102.40us 819.20us
Table 14-6: Example the accumulated low level time at 20 MHz
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 128 - Revision A4.0
14.11 PWM Power-down/Wakeup Procedures
The following flow diagrams describe the possible pwm procedures users require to take care prior to
the product power-down/wake-up. The power-down procedure below will result in PWM output a low
state after power-down. To output a high state, users may set PWMn to FFFh and initial state set to
high through option bit (EPOL/OPOL).
Figure 14-27: Example of PWM power-down procedure (pwm output low state)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 129 - Revision A4.0
Figure 14-28: Example of PWM wake-up from power-down procedure
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 130 - Revision A4.0
15. MOTION FEEDBACK MODULE
Motion feedback module is a peripheral module designed for motion feedback applications. This
module includes two sub-modules:
• Input Capture Module (IC).
• Quadrature Encoder Inte rface (QEI).
There are three 16-bit registers cascaded by two 8-bit SFR in motion feedback module, but with
different definitions in each sub-module. Together with Timer 3, these modules provide a number of
options for motion and control applications. Most of the features for the QEI and IC sub-modules are
fully programmable thus making a flexible peripheral structure that can accommodate a wide range of
uses. A simplified block diagram of the entire Motion Feedb ack module is shown in Figure 15-2.
Note: The input pins are common to the IC and QEI sub-modules, only one of these two sub-
modules may be used at any given time. IC sub-mod ule is the default value upon reset.
15.1 Input Capture Module (IC)
The capture modules are function to detect and measure pul se width and period of a squa re wave.
It supports 3 capture inputs and digital noise rejection filter. The modules are configured by CAPCON0
and CAPCON1 SFR registers. Input Capture 0, 1 & 2 have their own edge detector but share with one
timer i.e. Timer 3. The Input Capture pins structure are Schmitt trigger. For this operation it basically
consists of;
• 3 capture module function blocks.
• Timer 3 block.
Each capture module block consists of 2 bytes of capture registers, noise filter and programmable
edge triggers. Noise Filter is used to filter the unwanted glitch or pulse on the trigger input pin.
The noise filter can be enabled through bit ENFx (CAPCON1). If enabled, the capture logic required
to sample 4 consecutive same capture input value in order to recognize an edge as a capture event. A
possible implementation of digital noise filter is as follow; the interval between pulses requirement for
input capture is 1 machine cycle width, which is the same as the pulse width required to guarantee a
trigger for all trigger edge mode. For less than 3 system clocks, anything less than 3 clocks will not
have any trigger and pulse width of 3 or more but less than 4 clocks will trigger but will not guarantee
100% because input sampling is at stage C3 of the machine cycle.
Figure 15-1: Noise Filter
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 131 - Revision A4.0
The trigger option is programmable through CCTx [1:0] (CAPCON0). It supports positive edge,
negative edge and both edge triggers. Each capture module consists of an enable, ICEN0~2. [Note:
x=0, 1, 2 for capture 0, 1, 2 block].
Capture blocks are triggered by external pins IC0, IC1 and IC2, respectively. If ICENx is enabled, each
time the external pin triggers, the content of the free running 16 bits counter, TL3 & TH3 (from Timer 3
block) will be captured/transferred into the corresponding capture registers, CCLx and CCHx. This
action also causes the corresponding CPTFx flag bit in CAPCON1 to be set, and generate an interrupt
(if enabled by ECPTF bit in SFR, EIE1.4). The CPTF0-2 flags are logical “OR” to the interrupt module.
Input Capture 0~2 share one interrupt named Capture Interrupt. Flag is set by hardware and cleared
by software.
Setting the T3CR bit (T3MOD.3), will allow hardware to reset timer 3 automatically after the value of
TL3 and TH3 have been captured. Priority is given to T3CR to reset counter after capture the timer
value into the capture register. When RL3CMP/ = 0 (reload mode, with T3CR=0 and ENLD=1),
RCAP3 will be loaded into Timer 3 counter upon overflow. While the rest of the condition of
combination of setting for T3CR and ENLD will reset the counter to 0000H.
Noise
Filter
CPTF0
CCL0 CCH0
Capture0Block
[00]
[01]
[10] ICEN0
IC0
CCT0[1:0]
ENF0[1]
Capture1
Block
Capture2
Block
(Note)
IC1 IC2
CPTF1 CPTF2
With
Schmitt
Trigger
Fosc DIVby
1,4,16,32 TL3 TH3
RCAP3L RCAP3H
00
01
10
11
TR3
CCDIV[1:0]
CPTF0
CPTF1
CPTF2
CCLD[1:0]
CMP/RL3
ENLD
Timer3Block
=
0
1
TF3
CMP/RL3
TMF3
TMF3
CMP/RL3
TOVF3
Reset
Timer3
T3CR
CPTF0
CPTF1
CPTF2
Note:TOVF3 = Timer 3 overflow
TMF3 = Internal Timer 3 Flag signal.
Input Capture 2 block (refer to Figure 15-3).
Figure 15-2: Timer3/Capture/Compare/Reload modules
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 132 - Revision A4.0
Figure 15-3: Input Capture 2 block diagram
Note: When QEI enabled (QEIEN=1), i nput capture 2 (IC2) still can detect edge changes.
.
The following table shows the bits setting for enabling input capture 2 edge detection.
QEIEN DISIDX ICEN2 INPUT CAPTURE 2 EDGE DETECTION
0 Disabled.
0 X(don’t care)
1 Enabled.
0 Disabled.
1 0 1 Enabled.
1 1 X Disabled,
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 133 - Revision A4.0
Figure 15-4: Timing diagram for Input Capture
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 134 - Revision A4.0
Figure 15-5: Program flow for measurement with IC0 between pulses with falling edge detection (ACC is incremented in
interrupt service routine).
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 135 - Revision A4.0
Figure 15-6: Program flow for measurement with IC0 between pulses with rising edge detection (ACC is incremented in interrupt
service routine).
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 136 - Revision A4.0
Figure 15-7: Program flow for measurement with IC0 pulse width with rising and falling edge detection (ACC is incremented in
interrupt service routine).
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 137 - Revision A4.0
Figure 15-8: Compare/Reload Function
Figure 15-9: Input Capture 0 Triggers
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 138 - Revision A4.0
15.1.1 Compare Mode
Timer 3 can be configured for compare mode. The compare mode is enabled by setting the RL3CMP/
bit to 1 in the T3CON register. RCAP3 will serves as a compare register. As Timer 3 counting up,
upon matching with RCAP3 value, TF3 will be set (which will generate an interrupt request if enable
Timer 3 interrupt ET3 is enabled) and the timer reload from 0 and starts counting again.
15.1.2 Reload Mode
Timer 3 can be also be configured for reload mode. The reload mode is enabled by clearing the
RL3CMP/ bit to 0 in the T3CON register. In this mode, RCAP serves as a reload register. When timer
3 overflows, a reload is generated that causes the contents of the RCAP3L and RCAP3H registers to
be reloaded into the TL3 and TH3 registers, if ENLD is set. TF3 flag is set, and interrupt request is
generated if enable Timer 3 interrupt ET3 is enabled. However, if ENLD = 0, timer 3 will be reload with
0, and count up again.
Alternatively, other reload source is also possible by the input capture pins by configuring the CCLD
[1:0] bit. If the ICENx bit is set, then a trigger of external IC0, IC1 or IC2 pin (respectively) will also
cause a reload. This action also sets the CPTF0, CPTF1 or CPTF2 flag bit in SFR CAPCON1,
respectively.
15.2 Quadrature Encoder Interface (QEI)
The Quadrature Encoder Interface (QEI) decodes speed of rotation and motion sensor information. It
can be used in any application that uses quadrature encoder for feedback. The QEI block supports the
features as below:
z Two QEI phase inputs: QEA and QEB.
z 16-bit Up/Down Pulse Counter (PLSCNT) with 16-b it read access latched buffer (PCNT).
z Four pulse counter update modes:
　 − Mode0: x4 free-counting mode.
　 − Mode1: x2 free-counting mode.
　 − Mode2: x4 compare-counting mode.
　 − Mode3: x2 compare-counting mode.
z Three interrupt sources:
　 − Pulse counter interrupt (CPTF0/QEIF).
　 − Direction index of motion detection with direction interrupt (CPTF1/DIRF).
　 − Input Capture 2 interrupt (CPTF2).
z The three 16-bit SFRs in QEI share the same add resses with the capture counter registers.
INPUT CAPTURE MODE QEI MODE
Capture0 Counter Register
(CCH0, CCL0) Pulse Read Counter Register
(PCNTH, PCNTL)
Capture1 Counter Register
(CCH1, CCL1) Pulse Counter Register
(PLSCNTH, PLSCNTL)
Capture2 Counter Register
(CCH2, CCL2) Maximum Counter Register
(MAXCNTH, MAXCNTL)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 139 - Revision A4.0
In QEI mode, IC1 and IC0 work as QEB and QEA inputs respectively. QEA and QEB accept the
outputs from a quadrature encoded source, such as incremental optical shaft encoder. Two channels,
A and B, nominally 90 degrees out of phase, are required.
Noise
Filter
IC0/QEA
Noise
Filter
IC1/QEB
QEI
Control
Logic
MAXCNT/
Capture 2 register
PLSCNT/
Capture 1 register
PCNT/
Capture 0 register
Read access to
low byte of PCNT
Compare/Reload
Control Logic
Direction
Clock
Mode
Select bits
Noise
Filter
IC2
Figure 15-10: QEI Block Diagram
The QEI control logic detects the relation of phase lead/lag between QEA and QEB to produce
direction index (DIR) and clock to control pulse counter. The comparator/reload logic compares the
pulse counter and maximum count and control the function of reloading pulse counter in compare-
counting mode. In Free-counting mode, the pulse counter will counts until the 65535 value. In
Compare-counting mode, the pulse counter will count to MAXCNT value. The value of the pulse
counter is not affected during QEI mode changes, nor when the QEI is disabled altogether.
In QEI mode, when IC2 edge (rising/falling edge is programmable through CAPCON0) has been
detected, CPTF2 will be set (if QEIEN=ICEN2=1 and DISIDX=0), and the only way to clear it is by
software.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 140 - Revision A4.0
CHA*/CHB* - QEA/B after going through noise filter. See Figure 15-10.
Figure 15-11: QEA/QEB/IC2 timing requirement.
15.2.1 Free-counting mode
Pulse counter up or down counts according to direction index (DIR). When overflow or underflow
occurs, it sets flag QEIF.
15.2.2 Compare-counting mode
Pulse counter up or down counts according to direction index (DIR). On up counting, QEIF will be
asserted when PLSCNT overflows from MAXCNT to zero on the next QEA edge for x2 counting
mode, and on QEA/QEB edge for x4 counting mode. On down counting, QEIF will be asserted when
PLSCNT underflows from zero to MAXCNT on the next QEA edge for x2 counting mode, and on
QEA/QEB edge for x4 counting mode. This mode provides the position of a rotor to user. If a
quadrature encoder output 1024 pulses to QEA per round, user can write MAXCNT with 4095 in x4
mode or 2047 in x2 mode and reset PLSCNT at initial before rotor runs. When the PLSCNT reaches
MAXCNT, it means rotor runs one roun d on next QEA edge.
15.2.3 X2/X4 Counting modes
In X2 counting mo de , the pulse counter increases or decreases one on every QEA edge based on the
phase relationship of QEA and QEB signals, however:-
In X4 counting mode, the pulse counter increases or decreases one on every QEA and QEB edge
based on the phase relationshi p of QEA and QEB sig nals.
15.2.4 Direction of Count
If QEA lead QEB, the pulse counter is increased by 1. If QEA lags QEB, the pulse counter is
decreased by 1. The QEI control logic generates a signal that sets the DIR bit (QEICON.3); this in turn
determines the direction of the count. When QEA leads QEB, DIR is set (= 1), and the position counter
increments on every active edge. When QEA lags QEB, DIR is cleared, and the position counter
decrements on every active edge. Refer to below table.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 141 - Revision A4.0
PREVIOUS SIGNAL DETECTED
RISING FALLING
CURRENT
SIGNAL
DETECTED QEA QEB QEA QEB
COUNTING
CONTROL
(DIR)
9 INC (1)
QEA rising 9 DEC (0)
9 DEC (0)
QEA falling 9 INC (1)
9 INC (1)
QEB rising
9 DEC (0)
9 INC (1)
QEB falling 9 DEC (0)
Table 15-1: Direction of count
Figure 15-12: X4 Counting Mode
QEI x4 Counting mode provides for a finer resolution of the rotor position, since the counter
increments or decrements more frequently for each QEA/QEB input pulse pair than in QEI x2 mode.
This mode is selected by setting the QEI Mode Select bits to ‘00b’ or ‘10b’. In this mode, the QEI logic
detects every edge on every QEA and QEB input edg es.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 142 - Revision A4.0
Figure 15-13: X2 Counting Mode
QEI x2 Counting mode is selected by setting the QEI Mode Select bits (QEIM1:QEIM0) to ‘01b’ or
‘11b’. In this mode, the QEI logic detects every edge on the QEA input only. Every rising and falling
edge on the QEA signal clocks the p ulse counter.
15.2.5 Up-Counting
Under the forward direction the DIR bit is 1 when up-counting. Software needs to clear the QEIF flag.
For the free-counting mode counter will counts until it matches 65535 and next edges on the forward
direction will set the QEIF high and reset the PLSCNT to zero. For compare-counting mode counter
counts until the MAXCNT value and reload the counter to zero and starts counting up. Changes of
direction trigger a down-count and PLSCNT decreasing in counter value. For X2 mode, only CHA
edge will set QEIF while for X4 mode both CHA and CHB edges will set QEIF.
15.2.6 Down-Counting
A change of direction will causes the counter to down-count for x2/x4 counting mode. It is indicated
with the DIR bit as 0 and DIRF flag is set to 1. At this stage the PLSCNT will starts to down-count
from the MAXCNT value for compare-counting mode and while in free-counting mode it will starts to
down-count from 65535. The pulse counter will reload with MAXCNT when it down counts to zero in
compare-counting mode and sets QEIF to high in the next edge. In free-counting mode the counter
will count to 16 bits value before it reload the pulse counter with the value 65535 and set the QEIF
high in the next edge. For X2 mode, only CHA edge will set QEIF while for X4 mode both CHA and
CHB edges will set QEIF.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 143 - Revision A4.0
16. SERIAL PORT
The W79E22X SERIES has two enhanced serial ports that are functionally similar to the serial port of
the original 8052 family. Both the serial ports are full-duplex ports, and the W79E22X SERIES
provides additional features, such as Frame Error Detection and Automatic Address Recognition. The
serial port 0 can use Timer 1 or 2 as baud rate generator, but the serial port 1 only uses Timer 1 as
baud rate generator. However, note that if both serial ports are enabled the baud rate setting control of
UART1 is also from the setting of UART0. The serial ports are capable of synchronous and
asynchronous communication. In synchronous mode, the W79E22X SERIES generates the clock and
operates in half-duplex mode. In asynchronous mode, the serial ports can simultaneously transmit and
receive data. The transmit registers and the receive buffers are both addressed as SBUF (SBUF1 for
the second serial port), but any write to SBUF/SBUF1 writes to the transmit register while any read
from SBUF/SBUF1 reads from the receive buffer. Both serial ports can operate in four modes, as
described below. The de scriptions are for serial port 0, however, it also apply to the se cond serial port.
16.1 Mode 0
This mode provides half-duplex, synchronous communication with external devices. In this mode,
serial data is transmitted and received on the RXD line, and the W79E22X SERIES provides the shift
clock on TxD, whether the device is transmitting or receiving. Eight bits are transmitted or received per
frame, LSB first. The baud rate is 1/12 or 1/4 of the oscillator frequency, as determined by the SM2 bit
(SCON.5; 0 = 1/12; 1 = 1/4). This programmable baud rate is the only difference between the standard
8051/52 and the W79E22X SERIES in mode 0.
Any write to SBUF starts transmission. The shift clock is activated, and data is shifted out on RxD until
all eight bits are transmitted. If SM2 is 1, the data appears on RxD one clock period before the falling
edge of the shift clock on TxD. Then, the clock remains low for two clock periods before going high
again. If SM2 is 0, the data appears on RxD three clock periods before the falling edge of the shift
clock on TxD, and the clock on TxD remains low for six clock periods before going high again. This
ensures that, at the receiving end, the data on the RxD line can be clocked on the rising edge of the
shift clock or latched when the clock is low. The TI flag is set high in C1 following the end of
transmission. The functional block diagram is shown below.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 144 - Revision A4.0
1/12
Fosc
0TX CLOCK
RX CLOCK
TI
RI
TX SHIFT
TX START
RX SHIFT
LOAD SBUF
SHIFT CLOCK
RI
REN
SM2
CLOCK
SIN PAROUT SBUF
Read SBUF
Internal
Data Bus
Serial Controllor
CLOCK
LOAD
PARIN
TX START
Internal
Data Bus
Write to
SBUF
SOUT
Transmit Shift Register
Serial Interrupt
RXD
TXD
RXD
P3.0 Alternate
Input Function
P3.0 Alternate
Output Function
P3.1 Alternate
Output Function
1/4
1
Receive Shift Register
Figure 16-1 Serial Port Mode 0
The serial port receives data when REN is 1 and RI is zero. The shift clock (TxD) is activated, and the
serial port latches data on the rising edge of the shift clock. The external device should, therefore,
present data on the falling edge of the shift clock. This process continues until all eight bits have been
received. The RI flag is set in C1 following the last rising edge of the shift clock, which stops reception
until RI is cleared by the software.
16.2 Mode 1
In Mode 1, full-duplex asynchronous communication is used. Frames consist of ten bits transmitted on
TXD and received on RXD. The ten bits consist of a start bit (0), eight data bits (LSB first), and a stop
bit (1). When receiving, the stop bit goes into RB8 in SCON. The baud rate in this mode is 1/16 or 1/32
of the Timer 1 overflow, and since Timer 1 can be set to a wide range of values, a wide variation of
baud rates is possible.
Transmission begins with a write to SBUF but is synchronized with the divide-by-16 counter, not the
write to SBUF. The start bit is put on TxD at C1 following the first roll-over of the divide-by-16 counter,
and the next bit is placed at C1 following the next rollover. After all eight bits are transmitted, the stop
bit is transmitted. The TI flag is set in the next C1 state, or the tenth rollover of the divide-by-16
counter after the write to SBUF.
Reception is enabled when REN is high, and the serial port starts receiving data when it detects a
falling edge on RxD. The falling-edge detector monitors the RxD line at 16 times the selected baud
rate. When a falling edge is detected, the divide-by-16 counter is reset to align the bit boundaries with
the rollovers of the counter. The 16 states of the counter divide the bit time into 16 slic es. Bit detection
is done on a best-of-three basis using samples at the 8th, 9th and 10th counter states. If the first bit
after the falling edge is not 0, the start bit is invalid, reception is aborted immediately, and the serial
port resumes looking for a falling edge on RxD. If a valid start bit is detected, the rest of the bits are
shifted into SBUF. After shifting in eight data bits, the stop bit is received. Then, if;
1. RI is 0, and
2. SM2 is 0 or the received stop bit is 1,
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 145 - Revision A4.0
the stop bit goes into RB8, the eight data bits go into SBUF, and RI is set. Otherwise, the received
frame is lost. In the middle of the stop bit, the receiver resumes looking for a fallin g edge on RxD.
1/2
1/16 TX CLOCK
RX CLOCK
TI
RI
TX SHIFT
TX START
RX SHIFT
LOAD SBUF
SMOD
CLOCK
SIN D8
SBUF
Read SBUF
Internal
Data Bus
Serial
Controllor
CLOCK
LOAD
PARIN
TX START
Internal
Data Bus
Write to
SBUF SOUT
Transmit Shift Register
Serial Interrupt
TXD
RXD
PAROUT
RB8
START
STOP
0
1
BIT
DETECTOR
1-To-0
DETECTOR
SAMPLE
1/16
0
Timer 1
Overflow
1
Receive Shift Register
01
01
TCLK
RCLK
Timer 2
Overflow
Figure 16-2 Serial Port Mode 1
16.3 Mode 2
In Mode 2, full-duplex asynchronous communication is used. Frames consist of eleven bits: one start
bit (0), eight data bits (LSB first), a programmable ninth bit (TB8) and a stop bit (0). When receiving,
the ninth bit is put into RB8. The baud rate is 1/16 or 1/32 of the oscillator frequency, as determined by
SMOD in PCON.
Transmission begins with a write to SBUF but is synchronized with the divide-by-16 counter, not the
write to SBUF. The start bit is put on TxD pin at C1 following the first roll-over of the divide-by-16
counter, and the next bit is placed on TxD at C1 following the next rollover. After all nine bits of data
are transmitted, the stop bit is transmitted. The TI flag is set in the next C1 state, or the 11th rollover of
the divide-by-16 counter after the write to SBUF.
Reception is enabled when REN is high, and the serial port starts receiving data when it detects a
falling edge on RxD. The falling-edge detector monitors the RxD line at 16 times the selected baud
rate. When a falling edge is detected, the divide-by-16 counter is reset to align the bit boundaries with
the rollovers of the counter. The 16 states of the counter divide the bit time into 16 slic es. Bit detection
is done on a best-of-three basis using samples at the 8th, 9th and 10th counter states. If the first bit
after the falling edge is not 0, the start bit is invalid, reception is aborted, and the serial port resumes
looking for a falling edge on RxD. If a valid start bit is detected, the rest of the bits are shifted into
SBUF. After shifting in nine data bits, the stop bit is received. Then, if;
1. RI is 0, and
2. SM2 is 0 or the received stop bit is 1,
the stop bit goes into RB8, the eight data bits go into SBUF, and RI is set. Otherwise, the received
frame may be lost. In the middle of the stop bit, the receiver resumes looking for a falling edge on
RxD. The functional description is shown in the figure below.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 146 - Revision A4.0
1/2
1/16 TX CLOCK
RX CLOCK
TI
RI
TX SHIFT
TX START
RX SHIFT
LOAD SBUF
SMOD
CLOCK
SIN D8
SBUF
Read SBUF
Internal
Data Bus
Serial
Controllor
CLOCK
LOAD
PARIN
TX START
Internal
Data Bus
Write to
SBUF SOUT
Transmit Shift Register
Serial Interrupt
TXD
RXD
PAROUT
RB8
START
STOP
0
1
BIT
DETECTOR
1-To-0
DETECTOR
SAMPLE
1/16
0
Fosc/2
1
D8
TB8
Receive Shift Register
Figure 16-3 Serial Port Mode 2
16.4 Mode 3
This mode is the same as Mode 2, except that the baud rate is programmable. The program must
select the mode and baud rate in SCON before any communication can take place. Timer 1 should be
initialized if Mode 1 or Mode 3 will be us ed.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 147 - Revision A4.0
Figure 16-4 Serial Port Mode 3
SM0 SM1 MODE TYPE BAUD
CLOCK
FRAME
SIZE
START
BIT
STOP
BIT
9TH BIT
FUNCTION
0 0 0 Synch. 4 or 12 OSC 8 bits No No None
0 1 1 Asynch. Timer 1 or 2 10 bits 1 1 None
1 0 2 Asynch. 32 or 64 OSC 11 bits 1 1 0, 1
1 1 3 Asynch. Timer 1 or 2 11 bits 1 1 0, 1
Table 16-1: Serial Ports Modes
16.5 Framing Error Detection
A frame error occurs when a valid stop bit is not detected. This could indicate incorrect serial data
communication. Typically, a frame error is due to noise or contention on the serial communication line.
The W79E22X SERIES has the ability to detect framing errors and set a flag that can be checked by
software.
The frame error FE (FE_1) bit is located in SCON.7. This bit is SM0 in the standard 8051/52 family,
but, in the W79E22X SERIES, it serves a dual function and is called SM0/FE. There are actually two
separate flags, SM0 and FE. The flag that is actually accessed as SCON.7 is determined by SMOD0
(PCON.6). When SMOD0 is set to 1, the FE flag is accessed. When SMOD0 is set to 0, the SM0 flag
is accessed.
The FE bit is set to 1 by the hardware, but it must be cleared by the software. Once FE is set, any
frames received afterwards, even those without errors, do not clear the FE flag. The flag has to be
cleared by the software. Note that SMOD0 must be set to 1 while reading or writing FE.
16.6 Multiprocessor Communications
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 148 - Revision A4.0
Multiprocessor communication is available in modes 1, 2 and 3 and makes use of the 9th data bit and
the automatic address recognition feature. This approach eliminates the software overhead required to
check every received address and greatly simplifies the program.
In modes 2 and 3, address bytes are distinguished from data bytes by 9th bit set, which is set high in
address bytes. When the master processor wants to transmit a block of data to one of the slaves, it
first sends the address of the target slave(s). The slave processors have already set their SM2 bits
high so that they are only interrupted by an address byte. The automatic address recognition feature
then ensures that only the addressed slave is actually interrupted. This feature compares the received
byte to the slave’s Given or Broadcast address and only sets the RI flag if the bytes match. This slave
then clears the SM2 bit, clearing the way to receive the data bytes. The unaddressed slaves are not
affected, as they are still waiting for their address.
In mode 1, the 9th bit is the stop bit, which is 1 in valid frames. Therefore, if SM2 is 1, RI is only set if a
valid frame is received and if the received byte matches the Given or Broadcast address.
The master processor can selectively communicate with groups of slaves using the Given Address or
all the slaves can be addressed together using the Broadcast Address. The addresses for each slave
are defined by the SADDR and SADEN registers. The slave address is the 8-bit value specified in
SADDR. SADEN is a mask for the value in SADDR. If a bit position in SADEN is 0, then the
corresponding bit position in SADDR is a don't-care condition in the address comparison. Only those
bit positions in SADDR whose corresponding bits in SADEN are 1 are used to obtain the Given
Address. This provides flexibility to address multiple slaves without cha nging addresses in SADDR.
The following example sho ws h ow to setup the Given Addresses to address different slaves.
Slave 1:
SADDR 1010 0100
SADEN 1111 1010
Given 1010 0x0x
Slave 2:
SADDR 1010 0111
SADEN 1111 1001
Given 1010 0xx1
The Given Address for slaves 1 and 2 differ in the LSB. In slave 1, it is a don't-care, while, in slave 2, it
is 1. Thus, to communicate with only slave 1, the master must send an address with LSB = 0 (1010
0000). Similarly, bit 1 is 0 for slave 1 and don't-care for slave 2. Hence, to communicate only with
slave 2, the master has to transmit an address with bit 1 = 1 (1010 0011). If the master wishes to
communicate with both slaves simultaneously, then the address must have bit 0 = 1 and bit 1 = 0.
Since bit 3 is don't-care for both slaves, two different addresses can address both slaves (1010 0001
and 1010 0101).
The master can communicate with all the slaves simultaneously using the Broadcast Address. The
Broadcast Address is formed from the logical OR of the SADDR and SADEN registers. The zeros in
the result are don't–care values. In most cases, the Broadcast Address is FFh. In the previous case,
the Broadcast Address is (1111111X) for slave 1 and (11111111) for slave 2.
The SADDR and SADEN registers are located at addresses A9h and B9h, respectively. These two
registers default to 00h, so the Given Address and Broadcast Address default to XXXX XXXX (i.e., all
bits don't-care), which effectively removes the multiprocessor communications feature
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 149 - Revision A4.0
17. I2C SERIAL PORTS
The I2C bus uses two wires (SCL and SDA) to transfer information between devices connected to the
bus. The main features of the I2C bus are:
– Bi-directional data transfer between masters and slaves.
– Multi-master bus (no central master).
– Arbitration between simultaneously transmitting masters without corruption of serial d ata on the bus.
– Serial clock synchronization allows devices with different bit rates to communicate via one serial
bus.
– Serial clock synchronization can be used as a handshake mechanism to suspend and resume serial
transfer.
– The I2C bus may be used for test and diagn ostic purposes.
tBUF
STOP
SDA
SCL
START
tHD;STA
tLOW
tHD;DAT
tHIGH
tf
tSU;DAT
Repeated
START
tSU;STA tSU;STO
STOP
tr
Figure 17-1: I2C Bus Timing
The device’s on-chip I2C logic provides the serial interface that meets the I2C bus standard mode
specification. The I2C logic handles bytes transfer autonomously. It also keeps track of serial
transfers, and a status register (I2STATUS) reflects the status of the I2C bu s.
The I2C port, SCL and SDA are at P2.6 and P2.7. When the I/O pins are used as I2C port, user must
set the pins to logic high in advance. When I2C port is enabled by setting ENS to high, the internal
states will be controlled by I2CON and I2C logic hardware. Once a new status code is generated and
stored in I2STATUS, the I2C interrupt flag (SI) will be set automatically. If both EA and EI2C are also
in logic high, the I2C interrupt is requested. The 5 most significant bits of I2STATUS stores the internal
state code, the lowest 3 bits are always zero and the content keeps stable until SI is cleared by
software.
17.1 SIO Port
The SIO port is a serial I/O port, which supports all transfer modes from and to the I2C bus. The SIO
port handles byte transfers autonomously. To enable this port, the bit ENS1 in I2CON should be set to
'1'. The CPU interfaces to the SIO port through the seven special function registers. The detail
description of these registers can be found in the I2C Control registers section. The SIO H/W
interfaces to the I2C bus via two pins: SDA (P2.7, serial data line) and SCL (P2.6, serial clock line).
Pull up resistor is neede d for Pin P2.6 and P2.7 for I2C operation as these are 2 open drain pins.
17.2 The I2C Control Registers
The I2C has 1 control register (I2CON) to control the transmit/receive flow, 1 data register (I2DAT) to
buffer the Tx/Rx data, 1 status register (I2STATUS) to catch the state of Tx/Rx, recognizable slave
address register for slave mode use and 1 clock rate control block for master mode to generate the
variable baud rate.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 150 - Revision A4.0
SYMBOL DEFINITION ADDRESS MSB BIT_ADDRESS, SYMBOL LSB RESET
I2TIMER I 2 C Timer Counter
Register EFH - - - - - ENTI DIV4 TIF xxxx x000B
I2CLK I2C Clock Rate EEH I2CLK.7 I2CLK.6 I2CLK.5 I2CLK.4 I2CLK.3 I 2CLK.2 I2CLK.1 I2CLK.0 0000 0000B
I2STATUS I2C Status Register EDH I2STAT
US.7 I2STAT
US.6 I2STAT
US.5 I2STAT
US.4 I2STAT
US.3 - - - 1111 1000B
I2DAT I2C Data ECH I2DAT.7 I2DAT.6 I2DAT.5 I2DAT.4 I2DAT.3 I2DAT.2 I2DAT.1 I2DAT.0 0000 0000B
I2ADDR I2C Slave Address EAH ADDR.7 ADDR.6 ADDR.5 ADDR.4 ADDR.3 ADDR.2 ADDR.1 GC 0000 0000B
I2CON I2C Control Register E9H - ENS STA STO SI AA I2CI N - x000 000xB
I2CSADEN I2C Maskable Slave
Address F6H I2CSAD
EN.7 I2CSAD
EN.6 I2CSAD
EN.5 I2CSAD
EN.4 I2CSAD
EN.3 I2CSAD
EN.2 I2CSAD
EN.1 I2CSAD
EN.0 1111 1110B
Table 17-1: Control Registers of I2C Ports
17.2.1 Slave Address Registers, I2ADDR
I2C port is equipped with one slave address register. The contents of the register are irrelevant when
I2C is in master mode. In the slave mode, the seven most significant bits must be loaded with the
MCU’s own slave address. The I2C hardware will react if the contents of I2ADDR are matched with
the received slave address.
The I2C ports support the “General Call” function. If the GC bit is set the I2C port1 hardware will
respond to General Call address (0 0H). Clear GC bit to disable general call function.
When GC bit is set, the device is in slave mode which can receive the General Call address(00H) sent
by Master on the I2C bus. This special slave mode is referred to as GC mode.
17.2.2 Data Register, I2DAT
This register contains a byte of serial data to be transmitted or a byte which has just been received.
The CPU can read from or write to this 8-bit directly addressable SFR while it is not in the process of
shifting a byte. Data in I2DAT remains stable as long as SI is set. The MSB is shifted out first.While
data is being shifted out, data on the bus is simultaneously being shifted in; I2DAT always contains the
last data byte present on the bus. Thus, in the event of arbitration lost, the transition from master
transmitter to slave receiver is made with the correct data in I2DAT.
I2DAT and the acknowledge bit form a 9-bit shift register which shifts in or out an 8-bit byte, followed
by an acknowledge bit. The acknowledge bit is controlled by the hardware and cannot be accessed by
the CPU. Serial data is shifted into I2DAT on the rising edges of serial clock pulses on the SCL line.
When a byte has been shifted into I2DAT, the serial data is available in I2DAT, and the acknowledge
bit (ACK or NACK) is returned by the control logic during the ninth clock pulse. Serial data is shifted
out from I2DAT on the falling edges of SCL clock pulses, and is shifted into I2DAT on the rising edges
of SCL clock pulses.
I2DAT.7 I2DAT.6 I2DAT.5 I2DAT.4 I2DAT.3 I2DAT.2 I2DAT.1 I2DAT.0
I2C Data Register:
shifting direction
Figure 17-2: I2C Data Shift
17.2.3 Control Register, I2CON
The CPU can read from and write to this 8-bit, directly addressable SFR. Two bits are affected by
hardware: the SI bit is set when the I2C hardware requests a serial interrupt, and the STO bit is
cleared when a STOP con dition is present on the bus. The STO b i t is also cleared when ENS = "0".
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 151 - Revision A4.0
ENS I2C serial function block enable bit. When ENS=1 the I2C serial function enables. The
port latches of SDA1 and SCL1 must be set to logic high.
STA I2C START Flag. Setting STA to logic 1 to enter master mode, the I2C hardware sends a
START or repeat START condition to bus when the bus is free.
STO I2C STOP Flag. In master mode, setting STO to transmit a STOP condition to bus then
I2C hardware will check the bus condition if a STOP condition is detected this flag will be
cleared by hardware automatically. In a slave mode, setting STO resets I2C hardware to
the “not addressed slave mode”.
SI I2C Port 1 Interrupt Flag. When a new SIO state is present in the S1STA register, the SI
flag is set by hardware, and if the EA and EI2C1 bits are both set, the I2C1 interrupt is
requested. SI must be cleared by software.
AA Assert Acknowledge control bit. When AA=1 prior to address or data received, an
acknowledged (low level to SDA) will be returned during the acknowledge clock pulse on
the SCL line when; 1.) A slave is acknowledging the address sent from master, 2.) The
receiver devices are acknowledging the data sent by transmitter. When AA=0 prior to
address or data received, a not acknowledged (high level to SDA) will be returned during
the acknowledge clock pulse on the SCL line.
I2CIN By default it is zero and input are allows to come in through SDA pin. As when it is 1 input
is disallow and to prevent leakage current. During Po wer-Do wn mode input is disallow.
17.2.4 Status Register, I2STATUS
I2STATUS is an 8-bit read-only register. The three least significant bits are always 0. The five most
significant bits contain the status code. There are 23 possible status codes. When I2STATUS contains
F8H, no serial interrupt is requested. All other I2STATUS values correspond to defined I2C ports
states. When each of these states is entered, a status interrupt is requested (SI = 1). A valid status
code is present in I2STATUS one machine cycle after SI is set by hardware and is still present one
machine cycle after SI has been reset by software.
In addition, state 00H stands for a Bus Error. A Bus Error occurs when a START or STOP condition is
present at an illegal position in the format frame. Examples of illegal positions are during the serial
transfer of an address byte, a data byte or an acknowledge bit.
17.2.5 I2C Clock Baud Rate Control, I2CLK
The data baud rate of I2C is determines by I2CLK register when I2C port is in a master mode. It is not
important when I2C port is in a slave mode. In the slave modes, SIO will automatically synchronize
with any clock frequency up to 400 KHz from master I2C device.
The data baud rate of I2C setting conforms to the following equati on.
Data Baud Rate of I2C = FCPU / (I2CLK + 1), where FCPU = FOSC/4.
For example, if FOSC=16MHz, the I2CLK=40(28H), the data baud rate of I2C = (16MHz/4)/(40+1) =
97.56K bits/sec.
17.2.6 I2C Time-out Counter, I2Timer
In W79E22X SERIES, the I2C logic block provides a 14-bit timer-out counter that helps user to deal
with bus pending problem. When SI is cleared user can set ENTI=1 to start the time-out counter. If I2C
bus is pended too long to get any valid signal from devices on bus, the time-out counter overflows
cause TIF=1 to request an I2C interrupt. The I2C interrupt is requested in the condition of either SI=1
or TIF=1. Flags SI and TIF must be cleared by soft wa re.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 152 - Revision A4.0
17.2.7 I2C Maskable Slave Address
This register enables the Automatic Address Recognition feature of the I2C. When a bit in the
I2CSADEN is set to 1, the same bit location in I2CSADDR1 will be compared with the incoming serial
port data. When I2CSADEN.n is 0, then the bit becomes a don't-care in the comparison. This register
enables the Automatic Address Recognition feature of the I2C. When all the bits of I2CSADEN are 0,
interrupt will occur for any incoming address.
1
0
Fosc
1/4
14-bits Counter TIF
Clear Counter
ENTI
SI
DIV4
ENS1
To I2C Interrupt
Enable
SI
Figure 17-3: I2C Time-out Block Diagram
17.3 Modes of Operation
The on-chip I2C ports support five operation modes, Master transmitter, Master receiver, Slave
transmitter, Slave receiver, and GC call.
In a given application, I2C port may operate as a master or as a slave. In the slave mode, the I2C port
hardware looks for its own slave address and the general call address. If one of these addresses is
detected, and if the slave is willing to receive or transmit data from/to master(by setting the AA bit),
acknowledge pulse will be transmitted out on the 9th clock, hence an interrupt is requested on both
master and slave devices if interrupt is enabled. When the microcontroller wishes to become the bus
master, the hardware waits until the bus is free before the master mode is entered so that a possible
slave action is not interrupted. If bus arbitration is lost in the master mode, I2C port switches to the
slave mode immediately and can detect its own slave address in the same serial transfer.
17.3.1 Master Transmitter Mode
Serial data output through SDA while SCL outputs the serial clock. The first byte transmitted contains
the slave address of the receiving device (7 bits) and the data direction bit. In this case the data
direction bit (R/W) will be logic 0, and we say that a “W” is transmitted. Thus the first byte transmitted
is SLA+W. Serial data is transmitted 8 bits at a time. After each byte is transmitted, an acknowledge
bit is received. START and STOP conditions are output to indicate the beginning and the end of a
serial transfer.
17.3.2 Master Receiver Mode
In this case the data direction bit (R/W) will be logic 1, and we say that an “R” is transmitted. Thus the
first byte transmitted is SLA+R. Serial data is received via SDA while SCL outputs the serial clock.
Serial data is received 8 bits at a time. After each byte is received, an acknowledge bit is transmitted.
START and STOP conditions are output to indicate the beginning and end of a serial transfer.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 153 - Revision A4.0
17.3.3 Slave Receiver Mode
Serial data and the serial clock are received through SDA and SCL. After each byte is received, an
acknowledge bit is transmitted. START and STOP conditions are recognized as the beginning and
end of a serial transfer. Address recognition is performed by hardware after reception of the slave
address and direction bit.
17.3.4 Slave Transmitter Mode
The first byte is received and handled as in the slave receiver mode. However, in this mode, the
direction bit will indicate that the transfer direction is reversed. Serial data is transmitted via SDA while
the serial clock is input through SCL. START and STOP conditions are recognized as the beginning
and end of a serial transfer.
17.4 Data Transfer Flow in Five Operating Modes
The five operating modes are: Master/Transmitter, Master/Receiver, Slave/Transmitter,
Slave/Receiver and GC Call. Bits STA, STO and AA in I2CON register will determine the next state of
the SIO hardware after SI flag is cleared. Upon complexion of the new action, a new status code will
be updated and the SI flag will be set. If the I2C interrupt control bits (EA and EI2) are enabled,
appropriate action or software branch of the new status code can be performed in the Interrupt service
routine.
Data transfers in each mode are shown in the following figures.
Figure 17-4: Legend for I2C flow charts
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 154 - Revision A4.0
17.4.1 Master/Transmitter Mode
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 155 - Revision A4.0
17.4.2 Figure 17-5: Master Transmitter ModeMaster/Receiver Mode
Figure 17-6: Master Receiver Mode
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 156 - Revision A4.0
17.4.3 Slave/Transmitter Mode
Figure 17-7: Slave Transmitter Mode
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 157 - Revision A4.0
17.4.4 Slave/Receiver Mode
Figure 17-8: Slave Receiver Mode
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 158 - Revision A4.0
17.4.5 GC Mode
Figure 17-9: General Call Address
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 159 - Revision A4.0
18. SERIAL PERIPHERAL INTERFACE (SPI)
18.1 General descriptions
This device consists of SPI block to support high speed serial communication. It’s capable of
supporting data transfer rat es 5Mbit/s. This device’s SPI support the following features;
• Master and slave mode.
• Slave select output.
• Programmable seri al clock’s polarity and phase.
• Receive double buffered data register.
• LSB first enable.
• Write collision detection.
• Transfer complete interrupt.
18.2 Block descriptions
The Figure 18-1 shows SPI block diagram. It provides an overview of SPI architecture in this device. The
main blocks of SPI are the register bl ocks, control logics, baud rate control and pin control logics;
a. Shift register and read data buffer. It is single buffered in the transmit direction and double
buffered in the receive direction. Transmit data cannot be written to the shifter until the
previous transfer is complete. Receive logics consist of parallel read data buffer so the shifter
is free to accept a second data, as the first received data will be transferred to the read data
buffer.
b. SPI Control block. This provide control functions to configure the device for SPI enable,
master or slave, clock phase and polarity, LSB access first selection, and Slave Select output
enable.
c. Baud rate control. These control logics divide CPU clock to 4 different selectable clocks 1/8,
1/32, 1/128 and 1/2/256. Its’ selection is controllable through SPR [1:0] bits.
SPR1 SPR0 DIVIDER BAUD RATE
0 0 8 5MHz
0 1 32 1.25MHz
1 0 128 312.50kHz
1 1 256 156.25kHz
Table 18-1 SPI Baud Rate Selection (FOSC @ 40MHz)
d. SPI registers. There are three SPI registers to support its operations, they are;
• SPI control registers (SPCR)
• SPI status registers (SPSR)
• SPI data register (SPDR)
These registers provide control, status, data storage functions and baud rate selection control.
Detail bits descriptions are found at SFR section. When using SPI pull-up must be apply at bit
PUP0 = 1.
e. Pin control logic. Controls behavior of SPI interface pins.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 160 - Revision A4.0
Figure 18-1: SPI block diagram
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 161 - Revision A4.0
18.3 Functional descriptions
18.3.1 Master mode
The device can configure the SPI to operate as a master or as a slave, through MSTR bit. When the
MSTR bit is set, master mode is selected, when MSTR bit is cleared, slave mode is selected. During
master mode, only master SPI device can initiate transmission. A transmission begins by writing to the
master SPDR register. The bytes begin shifting out on MOSI pin under the control of SPCLK. The
master places data on MOSI line a half-cycle before SPCLK edge that the slave device uses to latch
the data bit. The SS must stay low before data transactions and stay low for the duration of the
transactions.
Figure 18-2: Master Mode Transmission (CPOL = 0, CPHA = 0)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 162 - Revision A4.0
SPCLK Cycles
SPCLK (Output,
CPOL=1)
MOSI/MISO
/SS (output to slave)
SPIF
Master writes to SPDR:
1. /SS asserted.
2. During master transmit, data is shifting out through MOSI.
During master receive, data is shifting in through MISO.
3. SPIF asserted at the end of transmission.
4. /SS negated.
Note:
When CPHA = 0, /SS output must go high between successive SPI characters.
When CP OL = 1, SP CL K idle high .
12345678
MSB 6 5 4 3 2 1 LSB
1
2
3
4
Master transfer in progress
Figure 18-3: Master Mode Transmission (CPOL = 1, CPHA = 0)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 163 - Revision A4.0
Figure 18-4: Master Mode Transmission (CPOL = 0, CPHA = 1)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 164 - Revision A4.0
Figure 18-5: Master Mode Transmission (CPOL = 1, CPHA = 1)
18.3.2 Slave Mode
When in slave mode, the SPCLK pin becomes input and it will be clock by another master SPI device.
The SS pin also becomes input. Similarly, before data transmissions occurs, and remain low until the
transmission completed. If SS goes high, the SPI is forced into idle state. If the SS is forced to high at
the middle of transmission, the transmission will be aborted and the receiving shifter buffer will be high
and goes into idle states.
Data flows from master to slave on MOSI pin and flows from slave to master on MISO pin. The SPDR
is used when transmitting or receiving data on the serial bus. Only a write to this register initiates
transmission or reception of a byte, and this only occurs in the master device. At the completion of
transferring a byte of data, the SPIF status bit is set in both the master and slave devices.
A read of the SPDR is actually a read of a buffer. To prevent an overrun and the loss of the byte that
caused the overrun, the first SPIF must be cleared by the time a second transfer of data from the shift
register to the read buffer is initiated.
Preliminary W79E225A/226A/227A Data Sheet
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- 165 - Revision A4.0
Figure 18-6: Slave Mode Transmission (CPOL = 0, CPHA = 0)
Preliminary W79E225A/226A/227A Data Sheet
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- 166 - Revision A4.0
Figure 18-7: Slave Mode Transmission (CPOL = 1, CPHA = 0)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 167 - Revision A4.0
Figure 18-8: Slave Mode Transmission (CPOL = 0, CPHA = 1)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 168 - Revision A4.0
Figure 18-9: Slave Mode Transmission (CPOL = 1, CPHA = 1)
18.3.3 Slave select
The slave select (SS) input of a slave device must be externally asserted before a master device can
exchange data with the slave device. SS must be low before data transactions and must stay low for
the duration of the transaction. The SS line of the master must be held high. The other three lines are
dedicated to the SPI whenever the serial peripheral interface is on.
The state of the master and slave CPHA bits affects the operation of SS. CPHA settings should be
identical for master and slave. When CPHA = 0, the shift clock is the OR of SS with SPCLK. In this
clock phase mode, SS must go high between successive characters in an SPI message. When
CPHA = 1, SS can be left low between successive SPI characters. In cases where there is only one
SPI slave MCU, its SS line can be tied to VSS as long as only CPHA = 1 clock mode is used.
18.3.4 /SS output
Available in master mode only, SS output is enabled with the SSOE bit in the SPCR register and
DRSS bit in the SPSR register. The SS output pin is connected to the SS input pin of the slave
device. The SS output automatically goes low for each transmission when selecting external device
and it goes high during each idling state to deselect external devices.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
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DRSS SSOE MASTER MODE SLAVE MODE
0 0
SS input ( With Mode Fault ) SS Input ( Not affected by SSOE )
0 1 Reserved SS Input ( Not affected by SSOE )
1 0
SS General purpose I/O ( No Mode Fault ) SS Input ( Not affected by SSOE )
1 1
SS output ( No Mode Fault ) SS Input ( Not affected by SSOE )
During master mode (with SSOE=DRSS= 0), mode fault will be set if SS pin is detected low. When
mode fault is detected hardware will clear MSTR bit and SPE bit in the meantime it will also generated
interrupt request, if ESPI is enabled.
Figure 18-10: SPI interrupt request
18.3.5 SPI I/O pins mode
When SPI is disabled (SPE = 0) the corresponding I/O is following the original setting and act as a
normal I/O. In the case of SPI is enabled (SPE = 1) the SPI pins I/O mode follow the below table. For
SS pin it is always at Quasi-bidirectional mode whether it is configured as master or slave.
MISO MOSI CLK /SS
Master Input Output Output
Output*: DRSS=0,SSOE=0
Input: DRSS=1, SSOE=1
Slave Output** during /SS = Low
Else Input mode Input Input Input
Input = Quasi-bidirectional mode
Output = Push-pull mode
Output* = this output mode in /SS is Quasi-bidirectional output mode. Master needs to detect
mode fault during master outputs /SS low.
Output** = In SLAVE mode, MISO is in output mode only during the time of SS =Low,
otherwise it must keep in input mode (Quasi-bidirectional).
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
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18.3.6 Programmable serial clock’s phase and polarity
The clock polarity CPOL control bit selects active high or active low SPCLK clock, and has no
significant effect on the transfer format. The clock phase CPHA control bit selects one of two different
transfer protocols by sampling data on odd numbered SPCLK edges or on even numbered SPCLK
edges. Thus, both these bits enable selection of four possible clo ck formats to be used by SPI system.
The clock phase and polarity should be identical for the master SPI device and the communicating
slave device.
When CPHA equals 0, the SS line must be negated and reasserted between each successive serial
byte. Also, if the slave writes data to the SPI data register (SPDR) while SS is low, a write collision
error results. When CPHA equals 1, the SS line can remain low between successive transfers. The
figures from
Figure 18-2 to
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 171 - Revision A4.0
Figure 18-9 show the SPI transfer format, with different CPOL and CPHA. When CPHA = 0, data is
sample on the first edge of SPCLK and whe n CPHA = 1 data is sample on the second edge of the
SPCLK. Prior to changing CPOL setting, SPE must be disabled first.
18.3.7 Receive double buffered data register
This device is single buffered in the transmit direction and double buffered in the receive direction.
This means that new data for transmission cannot be written to the shifter until the previous transfer is
complete; however, received data is transferred into a parallel read data buffer so the shifter is free to
accept a second serial byte.
As long as the first byte is read out of the read data buffer before the next byte is ready to be
transferred, no overrun condition occurs. If overrun occur, SPIOVF is set. Second byte serial data
cannot be transferred successfully into the data register during overrun condition and the data register
will remains the value of the previous byte. The figure below shows the receive data timing waveform
when overrun occur.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 172 - Revision A4.0
Figure 18-11: SPI Overrun Timing Waveform
18.3.8 LSB first enable
By default, this device transfer the SPI data most significant bit first. This device provides a control bit
SPCR.LSBFE to allow support of transfer of SPI data in least significant bit first.
18.3.9 Write Collision detection
Write collision indicates that an attempt was made to write data to the SPDR while a transfer was in
progress. SPDR is not double buffered in the transmit direction, any writes to SPDR cause data to be
written directly into the SPI shift register. This write corrupts any transfer in progress, a write collision
error is generated (WCOL will be set). The transfer continues undisturbed, and the write data that
caused the error is not written to the shifter. A write collision is normally a slave error because a slave
has no control over when a master initiates a transfer. A master knows when a transfer is in progress,
so there is no reason for a master to generate a write-collision error, although the SPI logic can detect
write collisions in both master and slave devices. WCOL flag is clear by software.
18.3.10 Transfer complete interrupt
This device consists of an interrupt flag at SPIF. This flag will be set upon completion of data transfer
with external device, or when a new data have been received and copied to SPDR. If interrupt is
enable (through ESPI), the SPI interrupt request will be generated, if global enable bit EA is also
enabled. SPIF is software clear.
18.3.11 Mode Fault
Error arises in a multiple-master system when more than one SPI device simultaneously tries to be a
master. This error is called a mode fault.
When the SPI system is configured as a master and the /SS input line goes to active low, a mode fault
error has occurred — usually because two devices have attempted to act as master at the same time.
In cases where more than one device is concurrently configured as a master, there is a chance of
contention between two pin drivers. For push-pull CMOS drivers, this contention can cause permanent
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 173 - Revision A4.0
damage. The mode fault mechanism attempts to protect the device by disabling the drivers. The
MSTR and SPE control bits in the SPCR associated with the SPI are cleared by hardware and an
interrupt is generated subject to masking by the ESPI control bit.
Other precautions may need to be taken to prevent driver damage. If two devices are made masters at
the same time, mode fault does not help protect either one unless one of them selects the other as
slave. The amount of damage possible depends on the length of time both devices attempt to act as
master.
MODF bit is set automatically by SPI hardware, if the MSTR control bit is set and the slave select input
pin becomes 0. This condition is not permitted in normal operation. In the case where /SS is set, it is
an output pin rather than being dedicated as the /SS input for the SPI system. In this special case, the
mode fault function is inhibited and MODF remain s cleared. This flag is cleared by software.
The following shows the sample hardware connection and s/w flow for multi-master/slave
environment. It shows how s/w handles mode fault.
Figure 18-12: SPI multi-master slave environment
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 174 - Revision A4.0
Figure 18-13: SPI multi-master slave s/w flow diagram
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 175 - Revision A4.0
19. ANALOG-TO-DIGITAL CONVERTER
The ADC contains a digital-to-analog converter (DAC) that converts the contents of a successive
approximation register to a voltage (VDAC), which is compared to the analog input voltage (Vin). The
output of the comparator is then fed back to the successive approximation control logic that controls
the successive approximation regi ster. This is illustrated in the figure below.
Figure 19-1: Successive Approximation ADC
19.1 Operation of ADC
A conversion can be initiated by software only or by either hardware or software. The software only
start mode is selected when control bit ADCCON.5 (ADCEX) =0. A conversion is then started by
setting control bit ADCCON.3 (ADCS) to 1. The hardware or software start mode is selected when
ADCCON.5 =1, and a conversion may be started by setting ADCCON.3 = 1 as above or by applying a
rising edge to external pin STADC (P4.0). When a conversion is started by applying a rising edge, a
low level must be applied to STADC for at least one machine cycle followed by a high level for at least
one machine cycle.
User sets ADCS to start converting then ADCS remains high while ADC is converting signal and will
be automatically cleared by hardware when ADC conversion is completed. The end of the 10-bit
conversion is flagged by control bit ADCCON.4 (ADCI). The upper 8 bits of the result are held in
special function register ADCH, and the two remaining bits are held in ADCL.1 (ADC.1) and ADCL.0
(ADC.0). The user may ignore the two least significant bits in ADCL and use the ADC as an 8-bit
converter (8 upper bits in ADCH). In any event, the total actual conversion time is 50 ADC clock input
cycles.
Control bits from ADCCON.0 to ADCCON.2 are used to control an analog multiplexer which selects
one of eight analog channels. An ADC conversion in progress is unaffected by an external or software
ADC start. The result of a completed conversion remains unaffected provided ADCI = logic 1. The
result of a completed conversion (ADCI = logic 1) remains unaffected when entering the idle mode.
The device supports maximum 8 analog input ports. 8 analog input ports share the I/O pins from P1.0
to P1.7. These I/O pins are switched to analog input ports by setting the bits of ADC Input Pin Select
Register (DDIO) to logic 1.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 176 - Revision A4.0
Figure 19-2: ADC Block Diagram
19.2 ADC Resolution and Analog Supply
The ADC circuit has its own supply pins (AVDD and AVSS) and one pins (Vref+) connected to each end
of the DAC’s resistance-ladder that the AVDD and Vref+ are connected to VDD and AVSS is connected to
VSS. The ladder has 1023 equally spaced taps, separated by a resistance of “R”. The first tap is
located 0.5×R above AVSS, and the last tap is located 0.5×R below Vref+. This gives a total ladder
resistance of 1024×R. This structure ensures that the DAC is monotonic and results in a symmetrical
quantization error.
For input voltages between AVSS and [(Vref+) + ½ LSB], the 10-bit result of an A/D conversion will be
0000000000B = 000H. For input voltages between [(Vref+) – 3/2 LSB] and Vref+, the result of a
conversion will be 1111111111B = 3FFH. AVref+ and AVSS may be between AVDD + 0.2V and AVSS –
0.2 V. Avref+ should be positive with respect to AVSS, and the input voltage (Vin) should be between
AVref+ and AVSS.
The result can always be calculated fro m the following formula:
Result = AVref
Vin
1024 +
× or Result =
VSS
VDD
1024×
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 177 - Revision A4.0
20. TIMED ACCESS PROTECTION
The W79E22X SERIES has features like the Watchdog Timer, wait-state control signal and power-
on/fail reset flag that are crucial to the proper operation of the system. If these features are
unprotected, errant code may write critical control bits, resulting in incorrect operation and loss of
control. To prevent this, the W79E22X SERIES provides has a timed-access protection scheme that
controls write access to critical bits.
In this scheme, protected bits have a timed write-enable window. A write is successful only if this
window is active; otherwise, the write is discarded. The write-enable window is opened in two steps.
First, the software writes AAh to the Timed Access (TA) register. This starts a counter, which expires
in three machine cycles. Then, if the software writes 55h to the TA register before the counter expires,
the write-enable window is opened for three machine cycles. After three machine cycles, the window
automatically closes, and the procedure must be re peated again to access protected bits.
The suggested code for opening the write-enable window is;
TA REG 0C7h ; Define new register TA, located at 0C7h
MOV TA, #0AAh
MOV TA, #055h
Five examples, some correct and some inco rrect, of using timed-access protection are shown below.
Example 1: Valid access
MOV TA, #0AAh ; 3 M/C ; Note: M/C = Machine Cycles
MOV TA, #055h ; 3 M/C
MOV WDCON, #00h ; 3 M/C
Example 2: Valid access
MOV TA, #0AAh ; 3 M/C
MOV TA, #055h ; 3 M/C
NOP ; 1 M/C
SETB EWT ; 2 M/C
Example 3: Valid access
MOV TA, #0Aah ; 3 M/C
MOV TA, #055h ; 3 M/C
ORL WDCON, #00000010B ; 3M/C
Example 4: Invalid access
MOV TA, #0AAh ; 3 M/C
MOV TA, #055h ; 3 M/C
NOP ; 1 M/C
NOP ; 1 M/C
CLR POR ; 2 M/C
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
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Example 5: Invalid Access
MOV TA, #0AAh 3 M/C
NOP 1 M/C
MOV TA, #055h 3 M/C
SETB EWT 2 M/C
In the first three examples, the protected bits are written before the window closes. In Example 4,
however, the write occurs after the window has closed, so there is no change in the protected bit. In
Example 5, the second write to TA occurs four machine cycles after the first write, so the timed access
window in not opened at all, and the writ e to the protected bit fails.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 179 - Revision A4.0
21. PORT 4 STRUCTURE
Port 4 is a multi-function port that performs general purpose I/O port and chip-select strobe signals
including read strobe, write strobe and read/write strobe signals. The 4 alternate modes are selected
by P4xM1 and P4xM0. The function of chip-select strobe output provides that user can activate
external devices by access to some specific a ddress region.
Port 4 Control Register A
Bit: 7 6 5 4 3 2 1 0
P41M1 P41M0 P41C1 P41C0 P40M1 P40M0 P40C1 P40C0
Mnemonic: P4CONA Address: 92h
Port 4 Control Register B
Bit: 7 6 5 4 3 2 1 0
P43M1 P43M0 P43C1 P43C0 P42M1 P42M0 P42C1 P42C0
Mnemonic: P4CONB Address: 93h
BIT NAME FUNCTION
P4xM1, P4xM0
Port 4 alternate modes.
=00: Mode 0. P4.x is a general purpose I/O port which is the same a s Po rt 1.
=01: Mode 1. P4.x is a Read Strobe signal for chip select purpose. The address
range depends on the SFR P4xAH, P4xAL and bits P4xC1, P4xC0.
=10: Mode 2. P4.x is a Write Strobe signal for chip select purpose. The address
range depends on the SFR P4xAH, P4xAL and bits P4xC1, P4xC0.
=11: Mode 3. P4.x is a Read/Write Strobe signal for chip select purpose. The
address range depends on the SFR P4xAH, P4xAL and bits P4xC1, P4xC0
P4xC1, P4xC0
Port 4 Chip-select Mode addres s comparison:
=00: Compare the full address (16 bits length) with the base address registers
P4xAH and P4xAL.
=01: Compare the 15 high bits (A15-
A
1) of address bus with the base address
registers P4xAH and P4xAL.
=10: Compare the 14 high bits (A15-A2) of address bus with the base address
registers P4xAH and P4xAL.
=11: Compare the 8 high bits (A15-
A
8) of address bus with the base address
registers P4xAH and P4xAL.
P40AH, P40AL:
The Base address registers for comparator of P4.0. P40AH contains the high-order byte of address;
P40AL contains the low-o r der byte of address.
P41AH, P41AL:
The Base address registers for comparator of P4.1. P41AH contains the high-order byte of address;
P41AL contains the low-o r der byte of address.
P42AH, P42AL:
The Base address registers for comparator of P4.2. P42AH contains the high-order byte of address;
P42AL contains the low-o r der byte of address.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 180 - Revision A4.0
P43AH, P43AL:
The Base address registers for comparator of P4.3. P43AH contains the high-order byte of address;
P43AL contains the low-o r der byte of address.
PORT 4
Bit: 7 6 5 4 3 2 1 0
- - - - P4.3 P4.2 P4.1 P4.0
Mnemonic: P4 Address: A5h
P4.3-0 Port 4 is a bi-directional I/O port with internal pull-ups.
PORT 4 CHIP-SELECT POLARITY
Bit: 7 6 5 4 3 2 1 0
P43INV P42INV P42INV P40INV - PWDNH RMWFP PUP0
Mnemonic: P4CSIN Address: A2h
P4xINV The active polarity of P4.x when it is set as a chip-select strobe output. High =
Active High. Low = Active Low.
PWDNH Set PWDNH to logic 1 then ALE and PSEN will keep high state, clear this bit to logic
0 then ALE and PSEN will output low during power down mode.
RMWFP Control Read Path of Instruction “Read-Modify-Write”. When this bit is set, the read
path of executing “read-modify-write” instruction is from port pin otherwise from
SFR.
PUP0 Enable Port 0 weak pull up.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 181 - Revision A4.0
ADDRESS BUS
Bit Length
Selectable
comparator
REGISTER
P4xAL
P4xAH
EQUAL
P4.x
MUX 4->1
P4 REGISTER
P4.x
READ
WRITE
DATA I/O
RD_CS
WR_CS
RD/WR_CS
P4xC0
P4xC1
P4xM0
P4xM1
P4xCSINV
P4.x INPUT DATA BUS
REGISTER
PIN
Figure 21-1 Port 4 Structure Diagram
Here is an example to program the P4.0 as a write strobe signal at the I/O port address 1234H
~1237H and positive polarity, and P4.1 ~ P4.3 are used as general I/O ports.
MOV P40AH, #12H
MOV P40AL, #34H ;Define the base I/O address 1234H for P4.0 as an special function
MOV P4CONA, #00001010B ;Define the P4.0 as a write strobe signal pin and the compared
address is [A15:A2]
MOV P4CONB, #00H ;P4.1~P4.3 as general I/O port whi ch are the same as PORT1
MOV P4CSIN, #10H ;Write the P40CSINV =1 to inverse the P4.0 write strobe polarity
Then any instruction writes data to address from 1234H to 1237H, for example MOVX @DPTR,A
(with DPTR=1234H~1237H), will generate the positive polarity write strobe signal at pin P4.0. And the
instruction of “MOV P4, #XX” will output the bit3 to bit1 of data #XX to pin P4.3~ P4.1.
Note: P4.2 and P4.3 pins are available in 48L LQFP packa ge only.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 182 - Revision A4.0
22. IN-SYSTEM PROGRAMMING
22.1 The Loader Program Locates at LDFlash Memory
CPU is Free Run at APFlash memory. CHPCON register had been set #03H value before CPU has
entered idle state. CPU will switch to LDFlash memory and execute a reset action. H/W reboot mode
will switch to LDFlash memory, too. Set SFRCN register where it locates at user's loader program to
update APFlash bank 0 memory. Set a SWRESET (CHPCON=#83H) to switch back APFlash after
CPU has updated APFlash program. CPU will restart to run program from reset state.
22.2 The Loader Program Locates at APFlash Memory
CPU is Free Run at APFlash memory. CHPCON register had been set #01H value before CPU has
entered idle state. Set SFRCN register to update LDFlash or another bank of APFlash program. CPU
will continue to run user's APFlash program after CPU has updated program. Please refer
demonstrative code to understand other detail description.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 183 - Revision A4.0
23. OPTION BITS
This device has two CONFIG bits (CONFIG0, CONFIG1) that must be define at power up and can not
be set after the program start of execution. Those features are configured through the use of two flash
EPROM bytes, and the flash EPROM can be programmed and verified repeatedly. Until the code
inside the Flash EPROM is confirmed OK, the code can be protected. The protection of flash EPROM
and those operations of the configuration bits are described below.
23.1 Config0
BIT DESCRIPTION
B0 =0: Lock data out
B1 =0: MOVC Inhibited
B2 =0; 1/2/2K Data Flash EPROM lock bit
B3 Reserved
B4 =1: Disable H/W reboot by P3.6 and P3.7
=0: Enable H/W reboot by P3.6 and P3.7
B5 =1: Disable H/W reboot by P4.3
=0: Enable H/W reboot by P4.3
Note: Support in 48L LQFP package only.
B6 Reserved
B7 =1: Crystal > 24MHz
=0: Crystal < 24MHz
Table 23-1 Config0 Option Bits
B0: Lock bit
This bit is used to protect the customer's program code in the W79E22X SERIES. After the
programmer finishes the programming and verifies sequence B0 can be cleared to logic 0 to protect
code from reading by any access path. Once this bit is set to logic 0, both the Flash EPROM data and
Special Setting Registers can not be accessed again.
B1: MOVC Inhibit
This bit is used to restrict the accessible region of the MOVC instruction. It can prevent the MOVC
instruction in external program memory from reading the internal program code. When this bit is set to
logic 0, a MOVC instruction in external program memory space will be able to access code only in the
external memory, not in the internal memory. A MOVC instruction in internal program memory space
will always be able to access the ROM data in both internal and external memory. If this bit is logic 1,
there are no restrictions on the MOVC in struction.
B4: H/W Reboot with P3.6 and P3.7
If this bit is set to logic 0, enable to reboot 4k LD Flash mode while RST =H, P3.6 = L and P3.7 = L
state. CPU will start from LD Flash to update the user’ s pro gram.
B5: H/W Reboot with P4.3
If this bit is set to logic 0, enable to reboot 4k LD Flash mode while RST =H and P4.3 = L state. CPU
will start from LD Flash to update the us er’s program
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 184 - Revision A4.0
B7: Select clock frequency.
If clock frequency is over 24MHz, then set this bit is H. If clock frequency is less than 24MHz, then
clear this bit.
23.2 Config1
BITS NAME FUNCTION
Bit 0 PWMOE PWM Odd Channel 1, 3 and 5 Enable.
1: Disable (default).
0: Enable odd PWM outputs to corresponding pins.
Bit 1 PWMEE PWM Even Channel 0, 2 and 4 Enable.
1: Disable (default)
0: Enable odd PWM outputs to corresponding pins.
Bit 2 OPOL
Define the polarity of PWM output after CPU reset, OPOL controls
odd PWM outputs.
1: Initial output high
0: Initial output low
Bit 3 EPOL
Define the polarity of PWM output after CPU reset, EPOL control even
PWM outputs.
1: Initial output high
0: Initial output low
Bit 4-5 - Reserved.
Bit 6 PWM6E
PWM Channel 6 Output Enable.
1: Disable (default).
0: Enable PWM6 output to corresponding pin.
Bit 7 PWM7E
PWM Channel 7 Output Enable.
1: Disable (default).
0: Enable PWM7 output to corresponding pin.
Table 23-2: Config 1 Option Bits
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 185 - Revision A4.0
24. ELECTRICAL CHARACTERISTICS
24.1 Absolute Maximum Ratings
SYMBOL PARAMETER CONDITION RATING UNIT
DC Power Supply VDD − VSS -0.3 +7.0 V
Input Voltage VIN VSS -0.3 VDD +0.3 V
Operating Temperature TA -40 +85 °C
Storage Temperature Tst -55 +150 °C
Note: Exposure to conditions beyond those listed under Absolute Maximum Ratings may adversely affect the life and reliability
of the device.
24.2 DC Characteristics
(VDD − VSS = 5V ±10%, TA = 25°C, Fosc = 20 MHz, unless otherwise specified.)
SPECIFICATION
PARAMETER SYMBOL
MIN TYP MAX
UNIT TEST CONDITIONS
VDD1 4.5 5.5 VDD =4.5V ~ 5.5V @
40MHz
VDD2 2.7 5.5 VDD =2.7V ~ 5.5V @
20MHz
VDD3 4.5 5.5 VDD =4.5V ~ 5.5V @
24MHz (external access)
Operating Voltage
VDD4 3.0
V
NVM program/erase
operation.
Run NOP
IDD1 - 58 65 mA
VDD=5.5V at 40MHz
Run NOP
IDD2 - 37 45 mA
VDD=5.5V at 20MHz
Run NOP
IDD3 - 15 20 mA
VDD=3.0V at 20MHz
Run NOP
IDD4 - 12 16 mA
VDD=2.7V at 20MHz
RST = VDD
IDD5 - 50 60 mA
VDD=5.5V at 40MHz
RST = VDD
IDD6 - 33 38 mA
VDD=5.5V at 20MHz
RST = VDD
IDD7 - 12 17 mA
VDD=3.0V at 20MHz
RST = VDD
Operating Current
IDD8 - 10 15 mA
VDD=2.7V at 20MHz
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 186 - Revision A4.0
DC Characteristics, continued
SPECIFICATION
PARAMETER SYMBOL
MIN TYP MAX
UNIT TEST CONDITIONS
35 42 mA VDD=5.5V at 40MHz (I/O
High)
IIDLE1 VDD=5.5V at 40MHz (I/O
Low)
mA VDD=5.5V at 20MHz (I/O
High)
IIDLE2 - 20 25
mA VDD=5.5V at 20MHz (I/O
Low)
VDD=3.0V at 20MHz (I/O
High)
IIDLE3 - 9 14 mA
VDD=3.0V at 20MHz (I/O
Low)
Idle Current
IIDLE4 - 8 11 mA VDD=2.7V at 20MHz
Power D own Current IPWDN - - 10 uA VDD=2.7V~5.5V
VDD=5.5V
Input Current P1, P2,
P3, P4, P5 IIN1 -95 -55 10 uA
VIN=0V or VDD
VDD=5.5V
Input Current RST IIN2 -10 50 300 uA
0<VIN<VDD
VDD=5.5V
Input Leakage Current
P0, /EA ILK -10 0 10 uA
0V<VIN<VDD
Logic 1 to 0 Transition
Current P1, P2, P3, P4,
P5 [*4] ITL[*4] -500 - -200 VDD = 5.5V
uA
VIN » 2.85V
Input Low Voltage P0,
P1, P2, P3, P4, P5, /EA
(Schmitt input) VIL1 0 0.8 0.3 VDD V VDD = 4.5V
Input High Voltage P0,
P1, P2, P3, P4, P5, /EA
(Schmitt input) VIH1 0.7 VDD 2. 0 VDD+0.2 V VDD = 5.5V
Hysteresis Voltage VHY - 0.2 VDD -
V IL21 - 1.0 1.6 VDD=4.5V
Input Low Voltage RST [*1] V IL22 - 0.7 0.8
V VDD=2.7V
VIH21 3.5 2.3
VDD+0.
2 VDD=5.5V
Input High Voltage RST [*1] VIH22 2 1.5
VDD+0.
2
V VDD=2.7V
V IL31 0 - 0.8 VDD=4.5V
Input Low Voltage
XTAL1[*3] V IL32 0 - 0.4 V VDD=2.7V
VIH31 4.0 - VDD+0.2 VDD=5.5V
Input High Voltage
XTAL1[*3] VIH32 2.5 - VDD+0.2 V VDD=2.7V
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 187 - Revision A4.0
DC Characteristics, continued
SPECIFICATION
PARAMETER SYMBOL
MIN TYP MAX
UNIT TEST CONDITIONS
ISR11 -22 -31 -42 VDD = 4.5V, VS = 2.4V Source Current
P2.0~P2.5, P5.0~P5.1
(PUSH-PULL Mode)
PWM pins ISR12 -6 -9 -13
mA VDD = 2.7V, VS = 2.0V
ISR21 -200 -300 -430 VDD = 4.5V, VS = 2.4V Source Current P1, P2,
P3, P4, P5 (Quasi-
bidirectional mode) ISR22 -50 -82 -115
uA VDD =2.7V, VS = 2.0V
ISK11 18 22 32 VDD = 4.5V, VS = 0.45V Sink Current P2.0~P2.5,
P5.0~P5.1 (PUSH-PULL
Mode) ISK12 10 15 25
mA VDD = 2.7V, VS = 0.45V
ISK21 4 5 6 VDD = 4.5V, VS = 0.45V Sink Current P0,P1,P2,
P3,P4,P5 (Quasi-
bidirectional mode) ISK22 3 3.5 5
mA VDD = 2.7V, VS = 0.45V
VOL11 - 0.35 - VDD = 4.5V, IOL = 20 mA Output Low Voltage
P2.0~P2.5, P5.0~P5.1
(PUSH-PULL Mode) VOL12 - 0.07 - V VDD = 2.7V, IOL = 3.2 mA
VOL21 - 0.35 - VDD = 4.5V, IOL = 4.0 mA Output Low Voltage P0,
P1, P2, P3, P4, P5
(Quasi-bidirectional
Mode) VOL22 - 0.35 - V VDD = 2.7V, IOL = 3.0 mA
VOH11 - 3.3 - VDD = 4.5V, IOH = -20mA Output High Voltage
P2.0~P2.5, P5.0~P5.1
(PUSH-PULL Mode) VOH12 - 2.5 - V VDD = 2.7V, IOH =-3.2mA
VOH21 - 4.1 - VDD = 4.5V, IOH =-100uA Output High Voltage P1,
P2, P3, P4, P5, P6, P7
(Quasi-bidirectional
Mode) VOH22 - 2.52 - V VDD = 2.7V, IOH = -30uA
Isk31 3 5 8 mA VDD=4.5V, Vs = 0.45V
Sink current [*2] P0, P2,
ALE, /PSEN Isk32 2.5 3.5 6 mA VDD=2.7V, Vs = 0.45V
Isr31 -6 -7.5 -9 mA VDD=4.5V, Vs = 2.4V
Source current [*2] P0,
P2, ALE, /PSEN Isr32 -1 -2 -3 mA VDD=2.7V, Vs = 2.0V
Notes: *1. RST pin is a Schmitt trigger input. RST has internal pull-low resistors about 60kΩ.
*2. P0, P2, ALE and /PSEN are tested in the external access mode.
*3. XTAL1 is a CMOS input.
*4. Pins of P1, P2, P3, P4, P5 can source a transition current when they are being externally driven from 1 to 0. The
transition current reaches its maximum value when VIN approximates to 2V.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 188 - Revision A4.0
24.3 AC Characteristics
tCLCL
tCLCX
tCHC
X
tCLCH
tCHCL
Clock
Note: Duty cycle is 50%.
24.3.1 External Clock Characteristics
PARAMETER SYMBOL MIN. TYP. MAX. UNITS NOTES
Clock High Time tCHCX 12 - - nS
Clock Low Time tCLCX 12 - - nS
Clock Rise Time tCLCH - - 10 nS
Clock Fall Time tCHCL - - 10 nS
24.3.2 AC Specification
(VDD − VSS = 5V ±10%, TA = 25°C, Fosc = 20 MHz, unless otherwise specified.)
PARAMETER SYMBOL
VARIABLE
CLOCK
MIN.
VARIABLE
CLOCK
MAX.
UNITS
Oscillator Frequency 1/tCLCL 0 401 MHz
Oscillator Frequency 1/tCLCL 0 242 MHz
ALE Pulse Width tLHLL 1.5tCLCL - 5 nS
Address Valid to ALE Low tAVLL 0.5tCLCL - 5 nS
Address Hold After ALE Low tLLAX1 0.5tCLCL - 5 nS
Address Hold After ALE Low for
MOVX Write tLLAX2 0.5tCLCL - 5 nS
ALE Low to Valid Instruction In tLLIV 2.5tCLCL - 20 nS
ALE Low to PSEN Low tLLPL 0.5tCLCL - 5 nS
PSEN Pulse Width tPLPH 2.0tCLCL - 5 nS
PSEN Low to Valid Instruction In tPLIV 2.0tCLCL - 20 nS
Input Instruction Hold After PSEN tPXIX 0 nS
Input Instruction Float After PSEN tPXIZ t
CLCL - 5 nS
Port 0 Address to Valid Instr. In tAVIV1 3.0tCLCL - 20 nS
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 189 - Revision A4.0
AC Specification, continued
PARAMETER SYMBOL
VARIABLE
CLOCK
MIN.
VARIABLE
CLOCK
MAX.
UNITS
Port 2 Address to Valid Instr. In tAVIV2 3.5tCLCL - 20 nS
PSEN Low to Address Float tPLAZ 0 nS
Data Hold After Read tRHDX 0 nS
Data Float After Read tRHDZ t
CLCL - 5 nS
RD Low to Address Float tRLAZ 0.5tCLCL - 5 nS
Note: 1. CPU executes the program stored in the internal APFlash at VDD=5.0V
2. CPU executes the program stored in the external memory at V DD=5.0V
24.3.3 MOVX Characteristics Using Stretch Memory Cycle
PARAMETER SYMBOL
VARIABLE
CLOCK
MIN.
VARIABLE
CLOCK
MAX.
UNITS STRECH
Data Access ALE Pulse Width tLLHL2 1.5tCLCL - 5
2.0tCLCL - 5 nS
tMCS = 0
tMCS>0
Address Hold After ALE Low
for MOVX write tLLAX2 0.5tCLCL - 5 nS
RD Pulse Width tRLRH 2.0tCLCL - 5
tMCS - 10 nS
tMCS = 0
tMCS>0
WR Pulse Width tWLWH 2.0tCLCL - 5
tMCS - 10 nS
tMCS = 0
tMCS>0
RD Low to Valid Data In tRLDV 2.0tCLCL - 20
tMCS - 20 nS tMCS = 0
tMCS>0
Data Hold after Read tRHDX 0 nS
Data Float after Read tRHDZ tCLCL - 5
2.0tCLCL - 5 nS tMCS = 0
tMCS>0
ALE Low to Valid Data In tLLDV 2.5tCLCL - 5
tMCS + 2tCLCL -
40 nS tMCS = 0
tMCS>0
Port 0 Address to Valid Data In tAVDV1 3.0tCLCL - 20
2.0tCLCL - 5 nS tMCS = 0
tMCS>0
ALE Low to RD or WR Low tLLWL 0.5tCLCL - 5
1.5tCLCL - 5 0.5tCLCL + 5
1.5tCLCL + 5 nS tMCS = 0
tMCS>0
Port 0 Address to RD or WR
Low tAVWL tCLCL - 5
2.0tCLCL - 5 nS
tMCS = 0
tMCS>0
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 190 - Revision A4.0
MOVX Characteristics Using Stretch Memory Cycle, continud
PARAMETER SYMBOL
VARIABLE
CLOCK
MIN.
VARIABLE
CLOCK
MAX.
UNITS STRECH
Port 2 Address to RD or WR
Low tAVWL2 1.5tCLCL - 5
2.5tCLCL - 5 nS
tMCS = 0
tMCS>0
Data Valid to WR Transition tQVWX -5
1.0tCLCL - 5 nS
tMCS = 0
tMCS>0
Data Hold after Write tWHQX tCLCL - 5
2.0tCLCL - 5 nS
tMCS = 0
tMCS>0
RD Low to Address Float tRLAZ 0.5tCLCL - 5 nS
RD or WR high to ALE high tWHLH 0
1.0tCLCL - 5 10
1.0tCLCL + 5 nS tMCS = 0
tMCS>0
Note: tMCS is a time period related to the Stretch memory cycle selection. The following table shows the time period of tMCS
for each selection of the Stretch value.
M2 M1 M0 MOVX CYCLES TMCS
0 0 0 2 machine cycles 0
0 0 1 3 machine cycles 4 tCLCL
0 1 0 4 machine cycles 8 tCLCL
0 1 1 5 machine cycles 12 tCLCL
1 0 0 6 machine cycles 16 tCLCL
1 0 1 7 machine cycles 20 tCLCL
1 1 0 8 machine cycles 24 tCLCL
1 1 1 9 machine cycles 28 tCLCL
Explanation of Logics Symbols
In order to maintain compatibility with the original 8051 family, this device specifies the same
parameter for each device, using the same symbols. The explanation of the symbols is as follows.
t Time A Address
C Clock D Input Data
H Logic level high L Logic level low
I Instruction P
PSEN
Q Output Data R RD signal
V Valid W
WR signal
X No longer a valid state Z Tri-state
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 191 - Revision A4.0
24.4 The ADC Converter DC ELECTRICAL CHARACTERISTICS
(VDD−VSS = 3.0~5V±10%, TA = -40 ~85 °C, Fosc = 20MHz, unless otherwise specified.)
SPECIFICATION
PARAMETER SYMBOL
MIN. TYP. MAX. UNIT
Analog input AVin VSS-0.2 VDD+0.2 V
ADC clock ADCCLK 200KHz - 5MHz Hz
Conversion time tC 52tADC1 us
Differential non-linearit y DNL -1 - +1 LSB
Integral non-linearity INL -2 - +2 LSB
Offset error Ofe -1 - +1 LSB
Gain error Ge -1 - +1 %
Absolute voltage error Ae -3 - +3 LSB
Notes:1. tADC: Th e period time of ADC input clock.
24.5 I2C Bus Timing Characteristics
STANDARD MODE I2C
BUS
PARAMETER SYMBOL
MIN. MAX.
UNIT
SCL clock frequency fSCL 0 100 kHz
bus free time between a STOP and START
condition tBUF 4.7 - uS
Hold time (repeated) START condition. After
this period, the first clock pulse is generated tHd;STA 4.0 - uS
Low period of the SCL clock tLOW 4.7 - uS
HIGH period of the SCL clock tHIGH 4.0 - uS
Set-up time for a repeated START condition tSU;STA 4.7 - uS
Data hold time tHD;DAT 5.0 - uS
Data set-up time tSU;DAT 250 - nS
Rise time of both SDA and SCL signals tr - 1000 nS
Fall time of both SDA and SCL signals tf - 300 nS
Set-up time for STOP condition tSU;STO 4.0 - uS
Capacitive load for each bus line Cb - 400 pF
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 192 - Revision A4.0
tBUF
STOP
SDA
SCL
START
tHD;STA
tLOW
tHD;DAT
tHIGH
tf
tSU;DAT
Repeated
START
tSU;STA tSU;STO
STOP
tr
Figure 24-1: I2C Bus Timing
24.6 Program Memory Read Cycle
tLLAX1
tPXIZ
tPLAZ
tLLPL
tPXIX
tPLIV
tAVIV2
tAVIV1
tPLPH
tAVLL
ADDRESS A8-A15ADDRESS A8-A15
ADDRESS
A0-A7
INSTRUCTION
IN
ADDRESS
A0-A7
PORT 2
PORT 0
PSEN
ALE tLLIV
tLHLL
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 193 - Revision A4.0
24.7 Data Memory Read Cycle
tAVLL
tAVWL1
tLLAX1
tWHLH
tRLDV
tRLRH
tRLAZ tRHDZ
tRHDX
tAVDV2
tAVDV1
tLLWL
ADDRESS A8-A15
ADDRESS
A0-A7
INSTRUCTION
IN DATA
IN
ADDRESS
A0-A7
PORT 2
PORT 0
PSEN
RD
ALE tLLDV
24.8 Data Memory Write Cycle
tAVLL
tAVWL1
tLLAX2
tWHLH
tWLWH
tQVWX tWHQX
tAVDV2
tLLWL
ADDRESS A8-A15
ADDRESS
A0-A7
INSTRUCTION
IN DATA OUT
ADDRESS
A0-A7
PORT 2
PORT 0
PSEN
WR
ALE
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 194 - Revision A4.0
25. TYPICAL APPLICATION CIRCUITS
25.1 Expanded External Program Memory and Crystal
VccVcc
AD13 A15
A5
AD3
AD5
AD7
AD4 AD4
A3
A11
A1
AD0
A6 AD5
AD1
AD3
A12
AD1
A2
AD1
A7
A2
AD5 AD6
A5
AD14
AD0
AD10
AD2
AD0
A13
A8
A3
A6
AD15
AD2
AD7
AD11
AD2
A9
AD9
AD6 A7
A14
AD4 A4
AD8
A0
AD6 AD7
AD3
A10
AD12
A0
A1
A4
Pin-diag ram of s t an dard 80 51
EA/VP
X1
X2
RESET
INT0
INT1
T0
T1
P1.0
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
P0.0
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7
P2.0
P2.1
P2.2
P2.3
P2.4
P2.5
P2.6
P2.7
RD
WR
PSEN
ALE/P
TXD
RXD
74F373
D0
3Q0 2
D1
4Q1 5
D2
7Q2 6
D3
8Q3 9
D4
13 Q4 12
D5
14 Q5 15
D6
17 Q6 16
D7
18 Q7 19
OC
1
G
11
8.2K
C2C1
CRYSTAL
27512
A0
10
A1
9
A2
8
A3
7
A4
6
A5
5
A6
4
A7
3
A8
25
A9
24
A10
21
A11
23
A12
2
A13
26
A14
27
A15
1
CE
20
OE
22
O0 11
O1 12
O2 13
O3 15
O4 16
O5 17
O6 18
O7 19
10u
R
Figure 25-1: Typical External Program Memory and Crystal connections
CRYSTAL C1 C2 R
16 MHz 0P~20P 0P~20P -
24 MHz 0P~12P 0P~12P -
33 MHz 10P 10P 10K~5.1K
40 MHz 1P 1P 10K~5.1K
The above table shows the reference values for crystal applications.
Note: C1, C2, R components refer to Figure above.
25.2 Expanded External Data Memory and Oscillator
Vcc
Vcc
Vcc
OSCILLATOR
AD0
AD3 AD3
A10
A4 AD5
A6
AD4
A1AD1
A11
A5
A0
AD4
AD7
AD9
AD7 A7
AD6
AD12
A2
AD1
AD7
AD2
A6
AD5
A12
AD6
A8
A1
AD6
AD1
A3
AD0
AD14
AD10
A13
AD3 A2
A7
AD0
AD5 A4
A9AD8
AD4
A14
A3 AD2
AD13
A5
AD11
A0
AD2
20256
CS
20 OE
22
WE
27
I/O0 11
I/O1 12
I/O2 13
I/O3 15
I/O4 16
I/O5 17
I/O6 18
I/O7 19
A0
10
A1
9
A2
8
A3
7
A4
6
A5
5
A6
4
A7
3
A8
25
A9
24
A10
21
A11
23
A12
2
A13
26
A14
1
VCC
28
Pin-diagram of s t andard 8051
EA/VP
X1
X2
RESET
INT0
INT1
T0
T1
P1.0
P1.1
P1.2
P1.3
P1.4
P1.5
P1.6
P1.7
P0.0
P0.1
P0.2
P0.3
P0.4
P0.5
P0.6
P0.7
P2.0
P2.1
P2.2
P2.3
P2.4
P2.5
P2.6
P2.7
RD
WR
PSEN
ALE/P
TXD
RXD
74F373
D0
3Q0 2
D1
4Q1 5
D2
7Q2 6
D3
8Q3 9
D4
13 Q4 12
D5
14 Q5 15
D6
17 Q6 16
D7
18 Q7 19
OC
1
G
11
10u
8.2K
Figure 25-2: Typical External Data Memory and Oscillator connections
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 195 - Revision A4.0
26. PACKAGE DIMENSION
26.1 44L PLCC
44 40
39
29
2818
17
7
61
L
c
1
b
2
A
H
D
D
eb
EH
E
y
A
A
1
Seating Plane
D
G
G
E
Symbol Min Nom Max Max
Nom
Min
Dimension in inch Dimension in mm
A
b
c
D
e
HE
L
y
A
A
1
2
E
b1
HD
G
GD
E
0.020
0.145
0.026
0.016
0.008
0.648
0.590
0.680
0.090
0.150
0.028
0.018
0.010
0.653
0.610
0.690
0.100
0.050 BSC
0.185
0.155
0.032
0.022
0.014
0.658
0.630
0.700
0.110
0.004
0.51
3.68
0.66
0.41
0.20
16.46
14.99
17.27
2.29
3.81
0.71
0.46
0.25
16.59
15.49
17.53
2.54
1.27
4.70
3.94
0.81
0.56
0.36
16.71
16.00
17.78
2.79
0.10
BSC
16.71
16.59
16.46
0.658
0.653
0.648
16.00
15.4914.99
0.6300.610
0.590
17.7817.53
17.27
0.700
0.690
0.680
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 196 - Revision A4.0
26.2 48L LQFP (7x7x1.4mm footprint 2.0mm)
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 197 - Revision A4.0
27. APPLICATION NOTE
In-system Programming Software Examples
This application note illustrates the in-system programmability of the Winbond W79E22X SERIES
Flash EPROM microcontroller. In this example, microcontroller will boot from APFlash bank and waiting
for a key to enter in-system programming mode for re-programming the contents of 64 KB APFlash.
While entering in-system programming mode, microcontroller executes the loader program in 4KB
LDFlash bank. The loader program erases the 64 KB APFlash then reads the new code data from
external SRAM buffer (or through other interfaces) to update the APFlash.
If the customer uses the reboot mode to update his program, please enable this b3 or b4 of security
bits from the writer. Please refer security bits for detail description.
EXAMPLE 1:
;*******************************************************************************************************************
;* Example of APFlash program: Program will scan the P1.0. If P1.0 = 0, enters in-system
;* programming mode for updating the content of APFlash cod e else executes the current ROM code.
;* XTAL = 24 MHz
;*******************************************************************************************************************
.chip 8052
.RAMCHK OFF
.symbols
CHPCON EQU 9FH
TA EQU C7H
SFRAL EQU ACH
SFRAH EQU ADH
SFRFD EQU AEH
SFRCN EQU AFH
ORG 0H
LJMP 100H ; JUMP TO MAIN PROGRAM
;************************************************************************
;* TIMER0 SERVICE VECTOR ORG = 000BH
;************************************************************************
ORG 00BH
CLR TR0 ; TR0 = 0, STOP TIMER0
MOV TL0, R6
MOV TH0,R7
RETI
;************************************************************************
;* APFlash MAIN PROGRAM
;************************************************************************
ORG 100H
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 198 - Revision A4.0
MAIN_APFlash:
MOV A, P1 ; SCAN P1.0
ANL A, #01H
CJNE A, #01H, PROGRAM_APFlash ; IF P1.0 = 0, ENTER IN-SYSTEM PROGRAMMING MODE
JMP NORMAL_MODE
PROGRAM_64:
MOV TA, #AAH ; CHPCON register is written protect by TA register.
MOV TA, #55H
MOV CHPCON, #03H ; CHPCON = 03H, ENTER IN-SYSTEM PROGRAMMING
MODE
MOV SFRCN, #0H
MOV TCON, #00H ; TR = 0 TIMER0 STOP
MOV IP, #00H ; IP = 00H
MOV IE, #82H ; TIMER0 INTERRUPT ENABLE FOR WAKE-UP FROM
IDLE MODE
MOV R6, #F0H ; TL0 = F0H
MOV R7, #FFH ; TH0 = FFH
MOV TL0, R6
MOV TH0, R7
MOV TMOD, #01H ; TMOD = 01H, SET TIMER0 A 16-BIT TIMER
MOV TCON, #10H ; TCON = 10H, TR0 = 1, GO
MOV PCON, #01H ; ENTER IDLE MODE FOR LAUNCHING THE IN-SYSTEM
PROGRAMMING
;************** ******************************************************************
;* Normal mode APFlashB APFlash prog ram: depending user's application
;********************************************************************************
NORMAL_MODE:
.
; User's application program
.
.
.
EXAMPLE 2:
;*******************************************************************************************************************
;* Example of 4KB LDFlash program: This loader program will erase the APFlashB APFlash first, then
reads the new ;* code from external SRAM and program them into APFlashB APFlash bank. XTAL =
24 MHz
;*******************************************************************************************************************
.chip 8052
.RAMCHK OFF
.symbols
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 199 - Revision A4.0
CHPCON EQU 9FH
TA EQU C7H
SFRAL EQU ACH
SFRAH EQU ADH
SFRFD EQU AEH
SFRCN EQU AFH
ORG 000H
LJMP 100H ; JUMP TO MAIN PROGRAM
;************************************************************************
;* 1. TIMER0 SERVICE VECTOR ORG = 0BH
;************************************************************************
ORG 000B
CLR TR0 ; TR0 = 0, STOP TIMER0
MOV TL0, R6
MOV TH0, R7
RETI
;************************************************************************
;* 4KB LDFlash MAIN PROGRAM
;************************************************************************
ORG 100H
MAIN_4K:
MOV TA, #AAH
MOV TA, #55H
MOV CHPCON, #03H ; CHPCON = 03H, ENABLE IN-SYSTEM PROGRAMMING.
MOV SFRCN, #0H
MOV TCON, #00H ; TCON = 00H, TR = 0 TIMER0 STOP
MOV TMOD, #01H ; TMOD = 01H, SET TIMER0 A 16BIT TIMER
MOV IP, #00H ; IP = 00H
MOV IE, #82H ; IE = 82H, TIMER0 INTERRUPT ENABLED
MOV R6, #F0H
MOV R7, #FFH
MOV TL0, R6
MOV TH0, R7
MOV TCON, #10H ; TCON = 10H, TR0 = 1, GO
MOV PCON, #01H ; ENTER IDLE MODE
UPDATE_APFlash:
MOV TCON, #00H ; TCON = 00H, TR = 0 TIM0 STOP
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 200 - Revision A4.0
MOV IP, #00H ; IP = 00H
MOV IE, #82H ; IE = 82H, TIMER0 INTERRUPT ENABLED
MOV TMOD, #01H ; TMOD = 01H, MODE1
MOV R6,#D0H ; SET WAKE-UP TIME FOR ERASE OPERATION, ABOUT
15 ms DEPENDING ON USER'S SYSTEM CLO CK RATE.
MOV R7, #8AH
MOV TL0, R6
MOV TH0, R7
ERASE_P_4K:
MOV SFRCN, #22H ; SFRCN = 22H, ERASE APFlash APFlash0
; SFRCN = A2H, ERASE APFlash1
MOV TCON, #10H ; TCON = 10H, TR0 = 1, GO
MOV PCON, #01H ; ENTER IDLE MODE (FOR ERASE OPERATION)
;*********************************************************************
;* BLANK CHECK
;*********************************************************************
MOV SFRCN, #0H ; SFRCN = 00H, READ AP FlashB APFlash0
; SFRCN = 80H, READ AP FlashB APFlash1
MOV SFRAH, #0H ; START ADDRESS = 0H
MOV SFRAL, #0H
MOV R6, #FDH ; SET TIMER FOR READ OPERATION, ABOUT 1.5 μS.
MOV R7, #FFH
MOV TL0, R6
MOV TH0, R7
blank_check_loop:
SETB TR0 ; Enable TIMER 0
MOV PCON, #01H ; Enter idle mode
MOV A, SFRFD ; Read one byte
CJNE A, #FFH, blank_check_error
INC SFRAL ; Next address
MOV A, SFRAL
JNZ blank_check_loop
INC SFRAH
MOV A, SFRAH
CJNE A, #0H, blank_check_loop ; End address = FFFFH
JMP PROGRAM_APFlashROM
blank_chec k_err or:
JMP $
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 201 - Revision A4.0
;*******************************************************************************
;* RE-PROGRAMMING APFlashB APFlash BANK
;*******************************************************************************
PROGRAM_APFlashROM:
MOV R2, #00H ; Target low byte address
MOV R1, #00H ; TARGET HIGH BYTE ADDRESS
MOV DPTR, #0H
MOV SFRAH, R1 ; SFRAH, Target high address
MOV SFRCN, #21H ; SFRCN = 21H, PROGR AM APFlash0
; SFRCN = A1H, PROGRAM APFlash1
MOV R6, #9CH ; SET TIMER FOR PROGRAMMING, ABOUT 50 μS.
MOV R7, #FFH
MOV TL0, R6
MOV TH0, R7
PROG_D_APFlash:
MOV SFRAL, R2 ; SFRAL = LOW BYTE ADDRESS
CALL GET_BYTE_FROM_PC_TO_ACC ; THIS PROGRAM IS BASED ON USER’S
CIRCUIT.
MOV @DPTR, A ; SAVE DATA INTO SRAM TO VERIFY CODE.
MOV SFRFD, A ; SFRFD = data IN
MOV TCON, #10H ; TCON = 10H, TR0 = 1,G O
MOV PCON, #01H ; ENTER IDLE MODE (PRORGAMMING)
INC DPTR
INC R2
CJNE R2, #0H, PROG_D_APFlash
INC R1
MOV SFRAH, R1
CJNE R1, #0H, PROG_D_APFlash
;*****************************************************************************
; * VERIFY APFlashB APFlash BANK
;*****************************************************************************
MOV R4, #03H ; ERROR COUNTER
MOV R6, #FDH ; SET TIMER FOR READ VERIFY, ABOUT 1.5 μS.
MOV R7, #FFH
MOV TL0, R6
MOV TH0, R7
MOV DPTR, #0H ; The start address of sample code
MOV R2, #0H ; Target low byte address
MOV R1, #0H ; Target high byte address
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 202 - Revision A4.0
MOV SFRAH, R1 ; SFRAH, Target high address
MOV SFRCN, #00H ; SFRCN = 00H, Read APFlash0
; SFRCN = 80H, Read APFlash1
READ_VERIFY_APFlash:
MOV SFRAL,R2 ; SFRAL = LOW ADDRESS
MOV TCON,#10H ; TCON = 10H, TR0 = 1,GO
MOV PCON,#01H
INC R2
MOVX A,@DPTR
INC DPTR
CJNE A,SFRFD,ERROR_APFlash
CJNE R2,#0H,READ_VERIFY_APFlash
INC R1
MOV SFRAH,R1
CJNE R1,#0H,READ_VERIFY_APFlash
;******************************************************************************
;* PROGRAMMING COMPLETLY, SOFTWARE RESET CPU
;******************************************************************************
MOV TA, #AAH
MOV TA, #55H
MOV CHPCON, #83H ; SOFTWARE RESET. CPU will restart from APFlash0
ERROR_APFlash:
DJNZ R4, UPDATE_APFlash ; IF ERROR OCCURS, REPEAT 3 TIMES.
. ; IN-SYST PROGRAMMING FAIL, USER'S PROCESS TO
DEAL WITH IT.
.
.
.
Preliminary W79E225A/226A/227A Data Sheet
Publication Release Date: April 1 5, 2008
- 203 - Revision A4.0
28. REVISION HISTORY
REVISION DATE PAGE DESCRIPTION
A1.0 October 18, 2007 - Preliminary version initially issued
A1.1 November 17, 2007
8,9
182
7
111
Incorrect pin number format. Re-alig nment.
Operating voltage for NVM program/erase min at
3.0V.
A
dded note for minimum NVM program/erase
operating voltage.
Updated Figure 14-8. Changed label “B” to “C”.
A2.0 December 11, 2007
8, 137,
138
99, 100
111
182
35
Removed INDX descriptions.
Updated diagram for T2EX at P4.1 pin.
Updated diagram. Posc replaced with Fosc.
Revise the Operating temperature to (-40, +85 ) °C
Revise the content of UART mode select table.
(SM0,SM1) is exchanged.
A3.0 March 17, 2008 141
6, 7 1. Modified UART descriptions.
2. Add two parts of W79E226 series
A4.0 April 15, 2008 68 Modified CPHA descriptions.
Important Notice
Winbond products are not designed, intended, authorized or warranted for use as components
in systems or equipment intended for surgical implantation, atomic energy control
instruments, airplane or spaceship instruments, transportation instruments, traffic signal
instruments, combustion control instruments, or for other applications intended to support or
sustain life. Further more, Winbond products are not intended for applications wherein failure
of Winbond products could result or lead to a situation wherein personal injury, death or
severe property or environmental damage could occur.
Winbond customers using or selling these products for use in such applications do so at their
own risk and agree to fully indemnify Winbond for any damages resulting from such improper
use or sales.