AX88796BLF - ASIX Electronics Corporation

ASIX ELECTRONICS CORPORATION First Released Date: 2006 / 03 / 01

4F, NO.8, HSIN ANN Rd., Science-based Industrial Park, Hsin-Chu City, Taiwan, R.O.C.

TEL: 886-3-579-9500 FAX: 886-3-579-9558 http://www.asix.com.tw

AX88796BLF / AX88796BLI

Low-pin-count Non-PCI 8/16-bit 10/100M Fast Ethernet Controller

Features Document No.: AX88796B_115/01/13/12

High-performance non-PCI local bus

Support both 8 bit and 16 bit local CPU interfaces

include MCS-51 series, 80186 series CPU and ISA

bus

SRAM-like host interface (US Patent Approval),

easily interfaced to most common embedded

MCUs

Embed 8Kx16 bits SRAM for packet buffers

Support Slave-DMA to minimize CPU overhead

Support burst-mode read for highest performance

applications

Interrupt pin with programmable Hold-off timer

Single-chip Fast Ethernet controller

Compatible with IEEE802.3, 802.3u standards

Integrate Fast Ethernet MAC/PHY transceiver in one

chip

Support 10Mbps and 100Mbps data rate

Support full and half duplex operations

Support 10/100Mbps N-way Auto-negotiation

operation

Support twisted pair crossover detection and

auto-correction (HP Auto-MDIX)

Support IEEE 802.3x flow control for full-duplex

operation

Support back-pressure flow control for half-duplex

operation

Support VLAN match filter

Support Wake-on-LAN function to reduce power by

following events

Detection of a change in the network link state

Receipt of a Magic Packet

Receipt of a MS wakeup frame

NE2000 register level compatible instruction

Performance can be enhanced with only a minor host

driver modification from original NE2000 driver

Support EEPROM interface to store MAC address

(Optional)

Support up to 2 (out) /1 (in/out) General Purpose pins

Support LED pins for various network activity

indications

Integrate voltage regulator and 25MHz crystal

oscillator

0.18um CMOS process. 3.3V power supply with 5V

tolerance I/O pins

64-pin LQFP , RoHS package

Operate over 0 to +70 C or -40 to +85 C temperature

range

Product description

The AX88796B is a low-pin-count (64-pin LQFP) non-PCI Ethernet controller for the Embedded and Industrial Ethernet

applications. The AX88796B supports 8/16-bit SRAM-like host interface, providing a glue-less connection to most

common embedded MCUs. The AX88796B integrates on-chip Fast Ethernet MAC and PHY, which is IEEE802.3

10Base-T and IEEE802.3u 100Base-TX compatible, and 8Kx16 bits embedded SRAM for packet buffering to

accommodate high bandwidth applications. The AX88796B has a wide array of features including support for Twisted

Pair Crossover Detection and Auto-Correction, Wake-on-LAN power management, and IEEE 802.3x and back-pressure

flow control. The AX88796B supports two operating temperature ranges, namely, commercial grade from 0 to 70 C and

industrial grade from –40 to 85 C. The small form factor of 64-pin LQFP package helps reduce the overall PCB space.

The programming of AX88796B is simple and compatible with NE2000, so the users don‟t need any modification and can

easily port the software drivers to many embedded systems very quickly. Combining these features with ASIX‟s free

TCP/IP software stack for 8-bit microcontrollers, AX88796B provides the best Ethernet solution for embedded

networking applications.

System Block Diagram

AX88796B

With

10/100 Mbps

PHY

8bit / 16bit

Non-PCI bus

51 series

/

186 bus

series

/

ISA bus

General

processor

AX88796B

With

10/100 Mbps

PHY

Interrupt

Address

Bus

CSn

RDn / WRn

Data Bus

2

AX88796BLF / AX88796BLI

DISCLAIMER

No part of this document may be reproduced or transmitted in any form or by any means, electronic or mechanical,

including photocopying and recording, for any purpose, without the express written permission of ASIX. ASIX may make

changes to the product specifications and descriptions in this document at any time, without notice.

ASIX provides this document “as is” without warranty of any kind, either expressed or implied, including without

limitation warranties of merchantability, fitness for a particular purpose, and non-infringement.

Designers must not rely on the absence or characteristics of any features or registers marked “reserved”, “undefined” or

“NC”. ASIX reserves these for future definition and shall have no responsibility whatsoever for conflicts or

incompatibilities arising from future changes to them. Always contact ASIX to get the latest document before starting a

design of ASIX products.

TRADEMARKS

ASIX, the ASIX logo are registered trademarks of ASIX Electronics Corporation. All other trademarks are the property of

their respective owners.

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AX88796BLF / AX88796BLI

Table of Contents

1.0 INTRODUCTION ...................................................................................................................................................... 7

1.1 GENERAL DESCRIPTION: ............................................................................................................................................ 7

1.2 AX88796B BLOCK DIAGRAM: .................................................................................................................................. 7

1.3 AX88796B PIN CONNECTION DIAGRAM ................................................................................................................... 8

2.0 SIGNAL DESCRIPTION .......................................................................................................................................... 9

2.1 LOCAL CPU BUS INTERFACE SIGNALS GROUP .......................................................................................................... 9

2.2 10/100MBPS TWISTED-PAIR INTERFACE PINS GROUP .............................................................................................. 10

2.3 BUILT-IN PHY LED INDICATOR PINS GROUP ........................................................................................................... 10

2.4 EEPROM SIGNALS GROUP ..................................................................................................................................... 10

2.5 MISCELLANEOUS PINS GROUP .................................................................................................................................. 11

3.0 MEMORY AND CSR MAPPING .......................................................................................................................... 12

3.1 EEPROM MEMORY MAPPING ................................................................................................................................ 12

3.2 CSR MAPPING ......................................................................................................................................................... 13

3.3 INTERNAL SRAM MEMORY MAPPING..................................................................................................................... 13

4.0 BASIC OPERATION ............................................................................................................................................... 15

4.1 RECEIVER FILTERING ............................................................................................................................................... 15

4.1.1 Unicast Address Match Filter ......................................................................................................................... 15

4.1.2 Multicast Address Match Filter ....................................................................................................................... 15

4.1.3 Broadcast Address Match Filter ..................................................................................................................... 16

4.1.4 VLAN Match Filter .......................................................................................................................................... 16

4.1.5 Aggregate Address Filter with Receive Configuration Setup .......................................................................... 17

4.2 BUFFER MANAGEMENT OPERATION ........................................................................................................................ 18

4.2.1 Packet Reception ............................................................................................................................................. 18

4.2.2 Packet Transmission ........................................................................................................................................ 21

4.2.3 Filling Packet to Transmit Buffer (Host fill data to memory) ......................................................................... 24

4.2.4 Removing Packets from the Ring (Host read data from memory) ................................................................... 24

4.2.5 Other Useful Operations ................................................................................................................................. 26

4.3 WAKE-UP DETECTION ............................................................................................................................................. 27

4.3.1 Wake-up frame ................................................................................................................................................ 27

4.3.2 Magic Packet frame......................................................................................................................................... 28

4.4 FLOW CONTROL ...................................................................................................................................................... 29

4.4.1 Full-Duplex Flow Control ............................................................................................................................... 29

4.4.2 Half-Duplex Flow Control .............................................................................................................................. 30

4.5 BIG- AND LITTLE-ENDIAN SUPPORT ......................................................................................................................... 30

4.6 GENERAL PURPOSE TIMER (GP TIMER) .................................................................................................................. 30

4.7 EEPROM INTERFACE ............................................................................................................................................. 31

4.8 POWER MANAGEMENT ............................................................................................................................................. 31

4.8.1 Power Management Event Indicators ............................................................................................................. 32

4.9 DEVICE READY OR BUSY......................................................................................................................................... 32

5.0 REGISTERS OPERATION .................................................................................................................................... 33

5.1 MAC CONTROL AND STATUS REGISTERS (CSR) ..................................................................................................... 33

5.1.1 Command Register (CR) .................................................................................................................................. 38

5.1.2 Rx Page Start Register (PSTART) ................................................................................................................... 39

5.1.3 Rx Page Stop Register (PSTOP) ...................................................................................................................... 39

5.1.4 Boundary Pointer (BNRY) ............................................................................................................................... 39

5.1.5 Transmit Page Start Address (TPSR) .............................................................................................................. 39

5.1.6 Transmit Status Register (TSR) ....................................................................................................................... 39

5.1.7 Transmit Byte Count Register (TBCR0) .......................................................................................................... 39

5.1.8 Number Of Collisions Register (NCR)............................................................................................................. 40

5.1.9 Transmit Byte Count Register (TBCR1) .......................................................................................................... 40

5.1.10 Current Page Register (CPR) ........................................................................................................................ 40

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AX88796BLF / AX88796BLI

5.1.11 Interrupt Status Register (ISR) ...................................................................................................................... 40

5.1.12 Remote Start Address Register (RSAR0) ....................................................................................................... 41

5.1.13 Remote Start Address Register (RSAR1) ....................................................................................................... 41

5.1.14 Remote Byte Count Register (RBCR0) .......................................................................................................... 41

5.1.15 Remote Byte Count Register (RBCR1) .......................................................................................................... 41

5.1.16 Current Remote DMA Address (CRDA0) ...................................................................................................... 41

5.1.17 Current Remote DMA Address (CRDA1) ...................................................................................................... 41

5.1.18 Receive Configuration Register (RCR) .......................................................................................................... 42

5.1.19 Receive Status Register (RSR) ....................................................................................................................... 42

5.1.20 Transmit Configuration Register (TCR) ........................................................................................................ 43

5.1.21 Frame Alignment Error Tally Register (CNTR0) .......................................................................................... 43

5.1.22 Data Configuration Register (DCR) .............................................................................................................. 43

5.1.23 CRC Error Tally Register (CNTR1) .............................................................................................................. 43

5.1.24 Interrupt mask register (IMR) ....................................................................................................................... 44

5.1.25 Frames Lost Tally Register (CNTR2) ............................................................................................................ 44

5.1.26 Physical Address Register 0 (PAR0) ............................................................................................................. 45

5.1.27 Physical Address Register 1 (PAR1) ............................................................................................................. 45

5.1.28 Physical Address Register 2 (PAR2) ............................................................................................................. 45

5.1.29 Physical Address Register 3 (PAR3) ............................................................................................................. 45

5.1.30 Physical Address Register 4 (PAR4) ............................................................................................................. 45

5.1.31 Physical Address Register 5 (PAR5) ............................................................................................................. 45

5.1.32 Current Page Register (CPR) ........................................................................................................................ 46

5.1.33 Multicast Address Register 0 (MAR0) ........................................................................................................... 46

5.1.34 Multicast Address Register 1 (MAR1) ........................................................................................................... 46

5.1.35 Multicast Address Register 2 (MAR2) ........................................................................................................... 46

5.1.36 Multicast Address Register 3 (MAR3) ........................................................................................................... 46

5.1.37 Multicast Address Register 4 (MAR4) ........................................................................................................... 46

5.1.38 Multicast Address Register 5 (MAR5) ........................................................................................................... 46

5.1.39 Multicast Address Register 6 (MAR6) ........................................................................................................... 46

5.1.40 Multicast Address Register 7 (MAR7) ........................................................................................................... 46

5.1.41 Total Receive Buffer Free Page Register (TFP) ............................................................................................ 47

5.1.42 Receive Configuration Register (RCR) .......................................................................................................... 47

5.1.43 Transmit Configuration Register (TCR) ........................................................................................................ 47

5.1.44 Data Configuration Register (DCR) .............................................................................................................. 47

5.1.45 Interrupt Mask Register (IMR) ...................................................................................................................... 47

5.1.46 Wakeup Frame Byte Mask (WFBM0) ............................................................................................................ 48

5.1.47 Wakeup Frame Byte Mask (WFBM1) ............................................................................................................ 48

5.1.48 Wakeup Frame Byte Mask (WFBM2) ............................................................................................................ 48

5.1.49 Wakeup Frame Byte Mask (WFBM3) ............................................................................................................ 48

5.1.50 Wakeup Frame 1,0 CRC (WF10CRC) ........................................................................................................... 48

5.1.51 Wakeup Frame 3,2 CRC (WF32CRC) ........................................................................................................... 48

5.1.52 Wakeup Frame Offset (WFOFST) ................................................................................................................. 49

5.1.53 Wakeup Frame Last Byte (WFLB) ................................................................................................................ 49

5.1.54 Wakeup Frame Command (WFCMD) .......................................................................................................... 49

5.1.55 Wakeup Control and Status Register (WUCSR) ........................................................................................... 49

5.1.56 Power Management Register (PMR) ............................................................................................................ 50

5.1.57 Reload EEPROM Register (REER) .............................................................................................................. 50

5.1.58 Misc. Control Register (MISC) ..................................................................................................................... 50

5.1.59 General Purpose Timer0 Register (GPT0) ................................................................................................... 50

5.1.60 General Purpose Timer1 Register (GPT1) ................................................................................................... 50

5.1.61 Data Port (DP) ............................................................................................................................................. 51

5.1.62 Inter-frame gap Segment 1(IFGS1) ............................................................................................................... 51

5.1.63 Inter-frame gap Segment 2(IFGS2) ............................................................................................................... 51

5.1.64 MII/EEPROM Management Register (MEMR) ............................................................................................. 51

5.1.65 I/O Buffer Type Configure Register (BTCR) ................................................................................................. 52

5.1.66 Inter-frame gap (IFG) ................................................................................................................................... 53

5.1.67 Back-pressure Jam Limit Count (BJLC) ........................................................................................................ 53

5.1.68 Device Status Register (DSR) ........................................................................................................................ 53

5.1.69 MAX Frame Size Register (MFSR0) .............................................................................................................. 53

5.1.70 MAX Frame Size Register (MFSR1) .............................................................................................................. 53

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AX88796BLF / AX88796BLI

5.1.71 Flow Control Register (FCR) ........................................................................................................................ 54

5.1.72 MAC Configure Register (MCR) ................................................................................................................... 54

5.1.73 VLAN ID 0 Register (VIDR0) ........................................................................................................................ 55

5.1.74 Current TX End Page Register (CTEPR) ...................................................................................................... 55

5.1.75 VLAN ID 1 Register (VIDR1) ........................................................................................................................ 55

5.1.76 Big-Endian Register (BER) ........................................................................................................................... 55

5.1.77 Host Wake Up Register (HWUR) .................................................................................................................. 55

5.1.78 Software Reset ............................................................................................................................................... 55

5.2 THE EMBEDDED PHY REGISTERS ........................................................................................................................... 56

5.2.1 MR0 -- Control Register Bit Descriptions ....................................................................................................... 57

5.2.2 MR1 -- Status Register Bit Descriptions .......................................................................................................... 58

5.2.3 MR2 -- Identification 1 Registers .................................................................................................................... 59

5.2.3 MR3 – Identification 2 Registers ..................................................................................................................... 59

5.2.4 MR4 – Autonegotiation Advertisement Register ............................................................................................. 59

5.2.5 MR5 – Autonegotiation Link Partner Ability (Base Page) Register ................................................................ 60

5.2.6 MR6 – Autonegotiation Expansion Register ................................................................................................... 61

6.0 CPU READ AND WRITE FUNCTIONS ............................................................................................................... 62

6.1 ISA BUS TYPE ACCESS FUNCTIONS. .......................................................................................................................... 62

6.2 80186 CPU BUS TYPE ACCESS FUNCTIONS. ............................................................................................................. 62

6.3 MCS-51 CPU BUS TYPE ACCESS FUNCTIONS. .......................................................................................................... 63

6.5 CPU ACCESS MII SERIAL MANAGEMENT INTERFACE ............................................................................................. 64

7.0 ELECTRICAL SPECIFICATION AND TIMINGS ............................................................................................. 65

7.1 ABSOLUTE MAXIMUM RATINGS .............................................................................................................................. 65

7.2 GENERAL OPERATION CONDITIONS ......................................................................................................................... 65

7.3 DC CHARACTERISTICS ............................................................................................................................................ 65

7.3.1 DC Characteristics of 3.3V with 5V Tolerance ............................................................................................... 65

7.3.2 Power Consumption ........................................................................................................................................ 66

7.3.3 Power-up Sequence ......................................................................................................................................... 67

7.4 AC TIMING CHARACTERISTICS ................................................................................................................................ 68

7.4.1 Reset Timing .................................................................................................................................................... 68

7.4.2 ISA Bus Access Timing .................................................................................................................................... 69

7.4.3 80186 Type I/O Access Timing ........................................................................................................................ 71

7.4.4 8051 Bus Access Timing .................................................................................................................................. 73

7.4.5 Burst Reads Access Timing ............................................................................................................................. 75

8.0 PACKAGE INFORMATION ................................................................................................................................. 76

9.0 ORDERING INFORMATION ............................................................................................................................... 77

APPENDIX A1: MCS51-LIKE (8-BIT) ...................................................................................................................... 78

APPENDIX A2: ISA-LIKE (8/16-BIT) ....................................................................................................................... 79

APPENDIX A3: 186-LIKE (16-BIT) ........................................................................................................................... 80

APPENDIX A4: CO-WORK WITH 32-BIT PROCESSOR ..................................................................................... 81

APPENDIX A5: BIG-ENDIAN PROCESSOR OF DATA BYTE LANDS .............................................................. 83

APPENDIX B: DISABLE AX88796B VOLTAGE REGULATOR .......................................................................... 84

REVERSION HISTORY ............................................................................................................................................... 85

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AX88796BLF / AX88796BLI

List of Figures

FIG - 1 AX88796B BLOCK DIAGRAM .................................................................................................................................. 7

FIG - 2 AX88796B PIN OUT DIAGRAM ................................................................................................................................ 8

FIG - 3 INTERNAL SRAM MAP ........................................................................................................................................... 14

FIG - 4 RECEIVE BUFFER RING........................................................................................................................................... 18

FIG - 5 RECEIVE BUFFER RING AT INITIALIZATION ............................................................................................................ 19

FIG - 6 TX / RX FLOW CONTROL ....................................................................................................................................... 29

FIG - 7 EEPROM CONNECTIONS ....................................................................................................................................... 31

FIG - 8 PME AND IRQ SIGNAL GENERATION ...................................................................................................................... 32

FIG - 9 SMI CONNECTIONS ................................................................................................................................................ 64

List of Tables

TAB - 1 LOCAL CPU BUS INTERFACE SIGNALS GROUP ....................................................................................................... 10

TAB - 2 10/100MBPS TWISTED-PAIR INTERFACES PINS GROUP.......................................................................................... 10

TAB - 3 BUILT-IN PHY LED INDICATOR PINS GROUP ......................................................................................................... 10

TAB - 4 EEPROM BUS INTERFACE SIGNALS GROUP .......................................................................................................... 10

TAB - 5 MISCELLANEOUS PINS GROUP ................................................................................................................................ 11

TAB - 6 EEPROM DATA FORMAT EXAMPLE ...................................................................................................................... 12

TAB - 7 CSR ADDRESS MAPPING ...................................................................................................................................... 13

TAB - 8 LOCAL MEMORY MAPPING ................................................................................................................................... 13

TAB - 9 INTERNAL SRAM MAP 00H ~ 1FH ...................................................................................................................... 13

TAB - 10 INTERNAL SRAM MAP 0400H ~ 040FH ............................................................................................................. 13

TAB - 11 BYTE LANE MAPPING ......................................................................................................................................... 30

TAB - 12 POWER MANAGEMENT STATUSES ...................................................................................................................... 31

TAB - 13 PAGE 0 OF MAC CORE REGISTERS MAPPING ...................................................................................................... 34

TAB - 14 PAGE 1 OF MAC CORE REGISTERS MAPPING ...................................................................................................... 35

TAB - 15 PAGE 2 OF MAC CORE REGISTERS MAPPING ...................................................................................................... 36

TAB - 16 PAGE 3 OF MAC CORE REGISTERS MAPPING ...................................................................................................... 37

TAB - 17 THE EMBEDDED PHY REGISTERS....................................................................................................................... 56

TAB - 18 SMI MANAGEMENT FRAME FORMAT ................................................................................................................. 64

TAB - 19 MII MANAGEMENT FRAMES- FIELD DESCRIPTION .............................................................................................. 64

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AX88796BLF / AX88796BLI

1.0 Introduction

1.1 General Description:

The AX88796B provides industrial standard NE2000 registers level compatible instruction set. Various drivers are

easily acquired, maintained, and used and no much additional effort is required. Software is easily port to various

embedded systems with no pain and tears. AX88796B also provides transmit queuing function to enhance standard

NE2000 of transmitting performance. Please contact ASIX Sales (Sales@asix.com.tw) to get the AX88x96B

Software Programming Guide for more details of AX88796B driver implementation.

The AX88796B Fast Ethernet Controller is a high performance and highly integrated local CPU bus Ethernet

Controller with embedded 10/100Mbps PHY/Transceiver and 8K*16 bit SRAM. The AX88796B supports both

8/16-bit local CPU interfaces including MCS-51 series, 80186 series, ISA bus and high-performance SRAM-like

interface. The simple host interface provides a glue-less connection to most common microprocessors and

microcontrollers. The AX88796B provides both 10Mbps and 100Mbps Ethernet function based on IEEE802.3 /

IEEE802.3u LAN standard.

1.2 AX88796B Block Diagram:

Fig - 1 AX88796B Block Diagram

(Optional)

8

AX88796BLF / AX88796BLI

1.3 AX88796B Pin Connection Diagram

The AX88796B is housed in the 64-pin plastic light quad flat pack. Fig - 2 AX88796B Pin Out Diagram

shows the AX88796B pinout diagram.

SA2

SA3

SA4

SA5,FIFO_SEL

VCC3IO

VCCK

SD0

SD1

SD2

SD3

SD4

SD5

SD6

SD7

SD8

SD9

48

47

46

45

44

43

42

41

40

39

38

37

36

35

34

33

SA1

49

AX88796B

32

SD10

SA0

50

31

SD11

AEN,PSEN

51

30

SD12

CSn

52

29

SD13

RDn

53

28

SD14

WRn

54

27

SD15

IOIS16

55

26

GND

TCLK

56

25

VCC3IO

TEST_CK_EN

57

24

VCCK

GND

58

23

IRQ

VCCK

59

22

PME

VCC18A

60

21

EECS

XTALIN

61

20

EECK

XTALOUT

62

19

EEDIO

GND18A

63

18

GND

RSET_BG

64

17

RSTn

o

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

VCC3A3

GND3A3

TPI+

TPI-

VCC18A

TPO+

TPO-

GND18A

V18F

VCC3R3

GND3R3

TEST2

TEST1

I_LK/ACT

I_SPEED

I_FULL/COL

Fig - 2 AX88796B Pin Out Diagram

9

AX88796BLF / AX88796BLI

2.0 Signal Description

The following abbreviations are used in AX88796B pinout:

All pin names with the “n” suffix are low-active signals.

The following abbreviations are used in following Tables.

I Input 1.8V

O Output 1.8V

I5 Input 3.3V with 5V tolerant

O5 Output 3.3V with 5V tolerant

T5 Tri-state with 5V tolerant

B5 Bi-directional I/O, 3.3V with 5V tolerant

4m 4mA driving strength

8m 8mA driving strength

S Schmitt trigger

PU Internal Pull Up 75Kohm

PD Internal Pull Down 75kohm

P Power Pin

A Analog

2.1 Local CPU Bus Interface Signals Group

Signal

Type

Pin No.

Description

SA[4:0]

I5

46, 47, 48, 49,

50

System Address: Signals SA[4:0] are address bus input lines. Used to

select internal CSR‟s.

SA[5] or

FIFO_SEL

I5/PD

45

System Address or FIFO Select: When driven high, all accesses to the

AX88796B are to the RX or TX data buffer FIFO (DP).

AX88796B supports two kinds of Data Port for receiving/transmitting

packets from/to AX88796B. One is the PIO Data Port (offset 10h); the

other one is the SRAM-like Data Port (e.g. offset 800h ~ FFFh for

Samsung2440 processor as described in Appendix A4 of AX88796B

datasheet). The SRAM-like Data Port address range depends on which

address line of host processor is being connected to the address line

SA5/FIFO_SEL of AX88796B.

Software on host CPU can issue Single Data Read/Write command to

both PIO Data Port and SRAM-like Data Port. However, to use Burst

Data Read/Write commands, one has to use SRAM-like Data Port,

which requires SA5/FIFO_SEL (pin 45) of AX88796B connecting to

an upper address line of host CPU. Our reference schematic has

SA5/FIFO_SEL pin connected to upper address line for supporting

Burst Data Read/Write commands.

SD[15:0]

B5/8m

27, 28, 29, 30,

31, 32, 33, 34,

35, 36, 37, 38,

39, 40, 41, 42

System Data Bus: Signals SD[15:0] constitute the bi-directional data

bus.

IRQ

O5/T5/8m

23

Programmable Interrupt request. Programmable polarity, source and

buffer types.

Can be configure by EEPROM auto-loader or BTCR (offset 15h)

CSn

I5

52

Chip Select: Active low.

RDn

I5

53

Read: Active low strobe to indicate a read cycle.

WRn

I5

54

Write: Active low strobe to indicate a write cycle. This signal also used

to wakeup the AX88796B when it is in reduced power state.

IOIS16n

T5/8m

55

16 Bit Port: For ISA bus used. The IOIS16n is asserted when the

address at the range corresponds to an I/O address to which the chip

responds, and the I/O port addressed is capable of 16-bit access.

AEN or PSEN

I5

51

Address Enable: When 186, ISA mode, this signal is active low to

access AX88796B.

PSEN: When 51 modes, this signal is active high to access

AX88796B.

10

AX88796BLF / AX88796BLI

PME

O5/T5/8m

22

Wakeup Indicator: When programmed to do so, is asserted when the

AX88696B detects a wake event and is requesting the system to wake

up from the D1 sleep state. The polarity and buffer type of this signal is

programmable by BTCR (offset 15h)

Tab - 1 Local CPU bus interface signals group

2.2 10/100Mbps Twisted-Pair Interface pins group

Signal

Type

Pin No.

Description

TPI+

AB

3

Twisted Pair Receive Input, Positive

TPI-

AB

4

Twisted Pair Receive Input, Negative

TPO+

AB

6

Twisted Pair Transmit Output, Positive

TPO-

AB

7

Twisted Pair Transmit Output, Negative

RSET_BG

AO

64

Off-chip resister. Must be connected 12.1K ohm ± 1% to ground.

Tab - 2 10/100Mbps Twisted-Pair Interfaces pins group

2.3 Built-in PHY LED indicator pins group

Signal

Type

Pin No.

Description

I_FULL/COL

O5/8m

16

Full-Duplex/Collision Status. If this signal is low, it indicates

full-duplex link established, and if it is high, then the link is in

half-duplex mode. When in half-duplex and collision occurrence, the

output will be driven low for 80ms and driven high at minimum 80ms.

I_SPEED

O5/8m

15

Speed Status: If this signal is low, it indicates 100Mbps, and if it is high,

then the speed is 10Mbps.

I_LK/ACT

O5/8m

14

Link Status/Active: If this signal is low, it indicates link, and if it is

high, then the link is fail. When in link status and line activity

occurrence, this signal is pulsed high (LED off) for 80ms whenever

transmit or receive activity is detected. This signal is then driven low

again for a minimum of 80ms, after which time it will repeat the process

if TX or RX activity is detected.

Tab - 3 Built-in PHY LED indicator pins group

2.4 EEPROM Signals Group

Signal

Type

Pin No.

Description

EECS

B5/4m/PD

21

EEPROM Chip Select: EEPROM chip select signal.

EECK

B5/4m/PD

20

EEPROM Clock: Signal connected to EEPROM clock pin.

EECS, EECK can load BUS type setting during power on reset cycle.

EECS

EECK

BUS TYPE

0

ISA BUS / SRAM-Like

0

1

80186

1

0

Reserved

1

MCS-51 (805X)

EEDIO

B5/4m/PU

19

EEPROM Data In/Out: Signal connected to EEPROM data input and

data output pin.

Tab - 4 EEPROM bus interface signals group

11

AX88796BLF / AX88796BLI

2.5 Miscellaneous pins group

Signal

Type

Pin No.

Description

XTALIN

I

61

Crystal/Oscillator Input: A 25Mhz crystal, +/- 50 PPM can be

connected across XTALIN and XTALOUT.

CMOS Local Clock: A 25Mhz clock, +/- 50 PPM, 40%-60% duty

cycle. Note that the pin does not support 3.3V or 5V voltage supply.

XTALOUT

O

62

Crystal/Oscillator Output: A 25Mhz crystal, +/- 50 PPM can be

connected across XTALIN and XTALOUT. If a single-ended external

clock (LCLK) is connected to XTALIN, the crystal output pin should

be left floating.

RSTn

I5/S

17

Reset:

Reset is active low then place AX88796B into reset mode. During the

rising edge the AX88796B loads the power on setting data.

TCLK

I5/PD

56

Test Clock Pins: As a clock input for ASIC testing only

No connection when normal operation

TEST_CK_EN

I5/PD/S

57

Enable TCLK in to ASIC as a main clock for test only.

No connection when normal operation

TEST2

I5/S

12

TEST mode select

Connect to ground when normal operation

TEST1

I5/S

13

TEST mode select

Connect to ground when normal operation

VCC3A3

P

1

Power Supply for Analog Circuit: +3.3V DC.

GND3A3

P

2

Power Supply for Analog Circuit: +0V DC or Ground Power.

VCC18A

P

5, 60

Analog power for oscillator, PLL, and Ethernet PHY differential I/O

pins, 1.8V

GND18A

P

8, 63

Analog ground for oscillator, PLL, and Ethernet PHY differential I/O

pins.

V18F

P

9

On-chip 3.3V to 1.8V Regulator output +1.8V DC.

VCC3R3

P

10

On-chip 3.3V to 1.8V Regulator power supply: +3.3V DC.

GND3R3

P

11

On-chip 3.3V to 1.8V Regulator ground.

GND

P

18, 26, 58

Ground.

VCC3IO

P

25, 44

Power Supply for IO: +3.3V DC.

VCCK

P

24, 43, 59

Power Supply for core logic: +1.8V DC.

Tab - 5 miscellaneous pins group

12

AX88796BLF / AX88796BLI

3.0 Memory and CSR Mapping

1. EEPROM Memory Mapping

2. CSR Mapping

3. Local Memory Mapping

3.1 EEPROM Memory Mapping

EEPROM interface can access via CSR offset 14h SMI/EEPROM registers when auto load operation completed.

The content of EEPROM data will be auto-loaded to internal memory from 0000h to 001Fh and from 0400h to 040Fh

automatically when hardware reset. It is similar to NE2000 PROM store Ethernet address. The real MAC address

must configured by PAR0 ~ PAR5 (CR page1 offset1 ~ offset6). The auto-loader only write to internal SRAM not

write to PAR0 ~ PAR5. An example as below, if the desired Ethernet physical address is 10-32-54-76-98-BA

It is a programmed EEPROM if auto-load value is 5AA5h from EEPROM address 0h. After hardware reset the

EEPROM loader will read first word and check pattern 5AA5h. If the first word value not equal to 5AA5h then the

EEPROM loader proclaimed that no external EEPROM or external EEPROM is a non-programmed EEPROM.

Addr

Bits

D[15:8]

D[7:0]

Description

5h

[15:0]

BAh

98h

MAC address 6th, 5th

4h

[15:0]

76h

54h

MAC address 4th, 3rd

3h

[15:0]

32h

10h

MAC address 2nd, 1st (multicast bit is 1st of bit_0)

2h

[15:11]

No define

Always zero

[10:8]

PHY_CONFIG

Configure internal PHY in different ways, such as 10BASE_T

half-duplex mode. If EEPROM auto loader not found 5AA5h

pattern in first word then internal PHY will be not been manual

configuration. (Default is Auto-negotiation enable with all

capabilities)

[10:8]

Function

000

Auto-negotiation enable with all capabilities

001

Auto-negotiation with 100BASE-TX FDX / HDX

ability

010

Auto-negotiation with 10BASE-T FDX / HDX

ability

011

Reserved

100

Manual selection of 100BASE-TX FDX

101

Manual selection of 100BASE-TX HDX

110

Manual selection of 10BASE-T FDX

111

Manual selection of 10BASE-T HDX

[7:6]

No define

Always zero

[5]

IRQ_TYPE_EEP

This bit will logic OR with BTCR (15h) bit-5 and will been

clear when host write BTCR. (Offset 15h)

[4]

IRQ_POL_EEP

This bit will logic OR with BTCR (15h) bit-4 and will been

clear when host write BTCR. (Offset 15h)

[3]

No define

Always zero

[2]

NE2000_PROM

When set, AX88796B internal memory map of 1Ch ~ 1Fh will

be configured to 57h. An ASCII code “W”. Otherwise

configured to 42h. An ASCII code “B”.

[1:0]

No define

Always zero

1h

[15:0]

00h

06h

Indicates the total of word counts for auto loading

0h

[15:0]

5Ah

A5h

Programmed pattern

Tab - 6 EEPROM data format example

13

AX88796BLF / AX88796BLI

3.2 CSR Mapping

System I/O Offset

Function

0000H ~ 001FH

AX88796B Command Status Register

Tab - 7 CSR Address Mapping

3.3 Internal SRAM Memory Mapping

Offset

Function

0000H ~ 001FH

Load from EEPROM

0020H ~ 03FFH

Reserved

0400H ~ 040FH

Load from EEPROM

0410H ~ 3FFFH

Reserved

4000H ~ 7FFFH

NE2000 compatible mode

8K x 16 SRAM Buffer

8000H ~ FFFFH

Reserved

Tab - 8 Local Memory Mapping

SRAM Address

D[15:8]

D[7:0]

1EH

57H / 42H

1CH

57H / 42H

1AH ~ 10H

00H

0AH

BAH

BAH (E‟NET ADDRESS 5)

08H

98H

98H (E‟NET ADDRESS 4)

06H

76H

76H (E‟NET ADDRESS 3)

04H

54H

54H (E‟NET ADDRESS 2)

02H

32H

32H (E‟NET ADDRESS 1)

00H

10H

10H (E‟NET ADDRESS 0)

Tab - 9 Internal SRAM Map 00H ~ 1FH

SRAM Address

D[15:8]

D[7:0]

40EH

57H

0406H ~ 040DH

00H

0404H

BAH (E‟NET ADDRESS 5)

98H (E‟NET ADDRESS 4)

0402H

76H (E‟NET ADDRESS 3)

54H (E‟NET ADDRESS 2)

0400H

32H (E‟NET ADDRESS 1)

10H (E‟NET ADDRESS 0)

Tab - 10 internal SRAM Map 0400H ~ 040FH

14

AX88796BLF / AX88796BLI

AX88796B internal memory address mapping

Fig - 3 Internal SRAM map

Page 0x40

(4000h)

Page 0x7F

(7F00h)

Page 0x80

(8000h)

Page Start (Page 0x4C)

(4C00h)

Page 0x4C

(4C00h)

Page Stop (Page 0x80)

(8000h)

 Every page equal to 256 Bytes

 Address of first BYTE in packet buffer

SRAM is Page 0x40, offset 0

 Address of last BYTE in packet buffer

SRAM is Page 0x7F, offset 0xff

Boundary Page Start (Page 0x4C)

Current Page (Page 0x4D)

TX Page Start Address (Page 0x40)

Transmit

buffer

Receive buffer

0h ~ 1Fh, Auto load MAC address

from external EEPROM

20h ~ 03FFh, Reserved

0400h ~ 040Fh, Auto load MAC

address from external EEPROM

0410h ~ 3FFFh, Reserved

(0000h)

(3FFFh)

15

AX88796BLF / AX88796BLI

4.0 Basic Operation

4.1 Receiver Filtering

The address filtering logic compares the Destination Address Field (first 6 bytes of the received packet) to the

Physical address registers stored in the Address Register Array. If any one of the six bytes does not match the

pre-programmed physical address, the Protocol Control Logic rejects the packet. This is for unicast address filtering.

All multicast destination addresses are filtered using a hashing algorithm. (See following description.) If the multicast

address indexes a bit that has been set in the filter bit array of the Multicast Address Register Array the packet is

accepted, otherwise the Protocol Control Logic rejects it. Each destination address is also checked for all 1‟s, which

is the reserved broadcast address.

4.1.1 Unicast Address Match Filter

The physical address registers are used to compare the destination address of incoming packets for rejecting or

accepting packets. Comparisons are performed on a byte wide basis. The bit assignment shown below relates the

sequence in PAR0-PAR5 to the bit sequence of the received packet.

D7

D6

D5

D4

D3

D2

D1

D0

PAR0

DA7

DA6

DA5

DA4

DA3

DA2

DA1

DA0

PAR1

DA15

DA14

DA13

DA12

DA11

DA10

DA9

DA8

PAR2

DA23

DA22

DA21

DA20

DA19

DA18

DA17

DA16

PAR3

DA31

DA30

DA29

DA28

DA27

DA26

DA25

DA24

PAR4

DA39

DA38

DA37

DA36

DA35

DA34

DA33

DA32

PAR5

DA47

DA46

DA45

DA44

DA43

DA42

DA41

DA40

Note: The bit sequence of the received packet is DA0, DA1, … DA7, DA8 ….

4.1.2 Multicast Address Match Filter

The Multicast Address Registers provide filtering of multicast addresses hashed by the CRC logic. All destination

addresses are fed through the 32 bits CRC generation logic and as the last bit of the destination address enters the

CRC, the 6 most significant bits of the CRC generator are latched. These 6 bits are then decoded by a 1 of 64 decode

to index a unique filter bit (FB0-63) in the Multicast Address Registers. If the filter bit selected is set, the multicast

packet is accepted. The system designer would use a program to determine which filter bits to set in the multicast

registers. All multicast filter bits that correspond to Multicast Address Registers accepted by the node are then set to

one. To accept all multicast packets all of the registers are set to all ones.

D7

D6

D5

D4

D3

D2

D1

D0

MAR0

FB7

FB6

FB5

FB4

FB3

FB2

FB1

FB0

MAR1

FB15

FB14

FB13

FB12

FB11

FB10

FB9

FB8

MAR2

FB23

FB22

FB21

FB20

FB19

FB18

FB17

FB16

MAR3

FB31

FB30

FB29

FB28

FB27

FB26

FB25

FB24

MAR4

FB39

FB38

FB37

FB36

FB35

FB34

FB33

FB32

MAR5

FB47

FB46

FB45

FB44

FB43

FB42

FB41

FB40

MAR6

FB55

FB54

FB53

FB52

FB51

FB50

FB49

FB48

MAR7

FB63

FB62

FB61

FB60

FB59

FB58

FB57

FB56

16

AX88796BLF / AX88796BLI

If address Y is found to hash to the value 32 (20H), then FB32 (ref. 4.1.2) in MAR4 should be initialized to ``1''. This

will cause the AX88796B to accept any multicast packet with the address Y.

Although the hashing algorithm does not guarantee perfect filtering of multicast address, it will perfectly filter up to

64 logical address filters if these addresses are chosen to map into unique locations in the multicast filter.

Note: The first bit of received packet sequence is 1‟s stands by Multicast Address.

4.1.3 Broadcast Address Match Filter

The Broadcast check logic compares the Destination Address Field (first 6 bytes of the received packet) to all 1‟s,

which is the values are “FF FF FF FF FF FF FF” in Hex format. If any bit of the six bytes does not equal to 1‟s, the

Protocol Control Logic rejects the packet.

4.1.4 VLAN Match Filter

AX88796B compares the thirteenth and fourteenth bytes of receive frames. If not match with VLAN_ID1,

VLAN_ID_0 (offset 1dh, 1ch) then reject current frame. The VLAN filter will always accept VLAN_ID is zero of

receive frames due to it is 802.1q (for priority purpose) frames. The maximum length of the good packet is thus

change from 1518 bytes to 1522 bytes.

32-bit CRC Generator

Latch

1 of 64-bit decoder

Filter bit array

X=31 to X=26

Clock

Selected bit

0 = reject, 1= accept

7 Bytes

Preamble SFD

1 Byte 6 Bytes 6 Bytes 2 B 46-1500 Bytes 4 Bytes

Destination

Address Source

Address L/T Data Pad FCS

Layer 2

Frame (64-1518 Bytes)

VLAN (64-1522 Bytes)

8100 TCI

2 B2 B

VLAN IDPriority CFI

802.1Q

VLAN tagging

3 bits 12 bits1 bit

17

AX88796BLF / AX88796BLI

4.1.5 Aggregate Address Filter with Receive Configuration Setup

The final address filter decision depends on the destination address types, identified by the above 4 address match

filters, and the setup of parameters of Receive Configuration Register.

Definitions of address match filter result are as following:

Signal

Value

Description

Phy

=1

Unicast Address Match

=0

Unicast Address not Match

Mul

=1

Multicast Address Match

=0

Multicast Address not Match

Bro

=1

Broadcast Address Match

=0

Broadcast Address not Match

VID

=1

VLAN ID Match

=0

VLAN ID not Match

AGG

=1

Aggregate Address Match

=0

Aggregate Address not Match

The meaning of AB, AM and PRO signals, please refer to “Receive Configuration Register” RCR (offset 0Ch)

The meaning of VLANE signal, Please refer to “MAC Configure Register” MCR (offset 1Bh)

Aggregate Address Filter function will be:

AB

Bro

/Mul

/Bro

PRO

Mul

/Bro

AM

Phy

VLANE

VID

AGG

18

AX88796BLF / AX88796BLI

4.2 Buffer Management Operation

There are four buffer memory access types used in AX88796B.

1. Packet Reception (Write data to memory from MAC)

2. Packet Transmission (Read data from memory to MAC)

3. Filling Packets to Transmit Buffer (Host fill data to memory)

4. Removing Packets from the Receive Buffer Ring (Host read data from memory)

The type 1 and 2 operations act as Local DMA. Type 1 does Local DMA write operation and type 2 does Local DMA

read operation. The type 3 and 4 operations act as Remote DMA. Type 3 does Remote DMA write operation and type

4 does Remote DMA read operation.

4.2.1 Packet Reception

The Local DMA receives channel uses a Buffer Ring Structure comprised of a series of contiguous fixed length 256

byte (128 word) buffers for storage of received packets. The location of the Receive Buffer Ring is programmed in

two registers, a Page Start and a Page Stop Register. Ethernet packets consist of minimum packet size (64 bytes) to

maximum packet size (1522 bytes), the 256 byte buffer length provides a good compromise between short packets

and longer packets to most efficiently use memory. In addition these buffers provide memory resources for storage of

back-to-back packets in loaded networks. Buffer Management Logic in the AX88796B controls the assignment of

buffers for storing packets. The Buffer Management Logic provides three basic functions: linking receive buffers for

long packets, recovery of buffers when a packet is rejected, and recalculation of buffer pages that have been read by

the host.

At initialization, a portion of the 16k byte (or 8k word) address space is reserved for the receiver buffer ring. Two

eight bit registers, the Page Start Address Register (PSTART) and the Page Stop Address Register (PSTOP) define

the physical boundaries of where the buffers reside. The AX88796B treats the list of buffers as a logical ring;

whenever the DMA address reaches the Page Stop Address, the DMA is reset to the Page Start Address.

Buffer #1

Buffer #2

Buffer #3

…

Buffer #n

Physical Memory Map Logic Receive Buffer Ring

Fig - 4 Receive Buffer Ring

4000h

8000h

Page Start

Page Stop

1

2

3

4

…

n-2

n-1

n

19

AX88796BLF / AX88796BLI

Initialization Of The Buffer Ring

Two static registers and two working registers control the operation of the Buffer Ring. These are the Page Start

Register, Page Stop Register (both described previously), the Current Page Register and the Boundary Pointer

Register. The Current Page Register points to the first buffer used to store a packet and is used to restore the DMA for

writing status to the Buffer Ring or for restoring the DMA address in the event of a Runt packet, a CRC, or Frame

Alignment error. The Boundary Register points to the first packet in the Ring not yet read by the host. If the local

DMA address ever reaches the Boundary, reception is aborted. The Boundary Pointer is also used to initialize the

Remote DMA for removing a packet and is advanced when a packet is removed. A simple analogy to remember the

function of these registers is that the Current Page Register acts as a Write Pointer and the Boundary Pointer acts as

a Read Pointer.

Buffer #1

Buffer #2

Buffer #3

…

Buffer #n

Physical Memory Map Logic Receive Buffer Ring

Fig - 5 Receive Buffer Ring At Initialization

Beginning Of Reception

When the first packet begins arriving the AX88796B and begins storing the packet at the location pointed to by the

Current Page Register. An offset of 4 bytes is reserved in this first buffer to allow room for storing receives status

corresponding to this packet.

Linking Receive Buffer Pages

If the length of the packet exhausts the first 256 bytes buffer, the DMA performs a forward link to the next buffer to

store the remainder of the packet. For a maximal length packet the buffer logic will link six buffers to store the entire

packet. Buffers cannot be skipped when linking; a packet will always be stored in contiguous buffers. Before the next

buffer can be linked, the Buffer Management Logic performs two comparisons. The first comparison tests for

equality between the DMA address of the next buffer and the contents of the Page Stop Register. If the buffer address

equals the Page Stop Register, the buffer management logic will restore the DMA to the first buffer in the Receive

Buffer Ring value programmed in the Page Start Address Register. The second of comparison test between the DMA

address of the next buffer address and the contents of the Boundary Pointer Register. If the two values are equal the

reception is aborted. The Boundary Pointer Register can be used to protect against overwriting any area in the receive

buffer that has not yet been read. When linking buffers, buffer management will never cross this pointer, effectively

avoiding any overwrites. If the buffer address does not match either the Boundary Pointer or Page Stop Address, the

link to the next buffer is performed.

4000h

8000h

Page Start

Page Stop

1

2

3

4

…

n-2

n-1

n

Boundary Page

Current Page

20

AX88796BLF / AX88796BLI

Linking Buffers

Before the DMA can enter the next contiguous 256 bytes buffer, the address is checked for equality to PSTOP and to

the Boundary Pointer. If neither is reached, the DMA is allowed to use the next buffer.

Buffer Ring Overflow

If the Buffer Ring has been filled and the DMA reaches the Boundary Pointer Address, reception of the current

incoming packet will be discard by the AX88796B. Thus, the packets previously received and still contained in the

Ring will not be destroyed.

End Of Packet Operations

At the end of the packet the AX88796B determines whether the received packet is to be accepted or rejected. It either

branch to a routine to store the or to another routine that recovers the buffers used to store the packet.

If current of packet is accepted then AX88796B write two words of buffer header on receive buffer.

Buffer Header

Description

NPR, Status

D[15:8]: Next Page Pointer

D[7:6]: always zero

D[5]: multicast or broadcast

D[4]: runt packet

D[3]: MII error

D[2]: alignment error

D[1]: CRC error

D[0]: good packet

Length

D[15:11]: always zero

D[10:0]: packet length

Successful Reception

If the packet is successfully received as shown, the DMA is restored to the first buffer used to store the packet

(pointed to by the Current Page Register). The DMA then stores the Receive Status, a Pointer to where the next

packet will be stored and the number of received bytes. Note that the remaining bytes in the last buffer are discarded

and reception of the next packet begins on the next empty 256 byte buffer boundary. The Current Page Register is

then initialized to the next available buffer in the Buffer Ring. (The location of the next buffer had been previously

calculated and temporarily stored in an internal scratchpad register.)

Buffer Recovery For Rejected Packets

If the packet is a runt packet or contains CRC or Frame Alignment errors, it is rejected. The buffer management logic

resets the DMA back to the first buffer page used to store the packet (pointed to by CPR), recovering all buffers that

had been used to store the rejected packet. This operation will not be performed if the AX88796B is programmed to

accept either runt packets or packets with CRC or Frame Alignment errors. The received CRC is always stored in

buffer memory after the last byte of received data for the packet.

21

AX88796BLF / AX88796BLI

4.2.2 Packet Transmission

The Local DMA Read is also used during transmission of a packet. Three registers control the DMA transfer during

transmission, a Transmit Page Start Address Register (TPSR) and the Transmit Byte Count Registers (TBCR0, 1).

When the AX88796B receives a command to transmit the packet pointed to by these registers, buffer memory data

will be moved into the FIFO as required during transmission. The AX88796B Controller will generate and append

the preamble, synch and CRC fields. AX88796B supports options of transmit queue function to enhance transmit

performance.

Original NE2000 Of Transmit Buffer

Options Of Transmit Buffer As A Ring

Options Back-To-Back Transmission (TX Command Queue)

TPSR

TBCR

1, 0

TX Page Start Address (0x40)

Transmit buffer

Receive buffer

AX88796B remote DMA

write default operation is

continue to write next address

even over transmit buffer area.

Host can do whole memory

read / write testing. And host

must handle the transmit data

do not overwrite receive

buffer area when performing

fill transmit data to transmit

buffer.

TX Page Start Address (0x40)

Transmit buffer

Receive buffer

When active Transmit Buffer

Ring Enable (CR page3 of

offset 0Dh). AX88796B

remote DMA write operation

will role over from last

transmit page to first transmit

page. Host no need reassign

RSAR0, RSAR1 again to fill

transmit data for first page.

Rx Page Start Register,

PSTART (CR page0, offset

01h)

Rx Page Start Register,

PSTART (CR page0, offset

01h)

TX Command Queue

Push In

Pop Out

When active TX Queue Enable

(offset 1Bh), Host can continue

Writing TXP (bit 2 of CR

register) to push TPSR and

TBCR1, 0 into AX88796B TX

command queue as long as

Transmit buffer has enough

vacancy and CTEPR (offset

1Ch) bit7 is „0‟(Not full). After

current packet transmitted

completely, MAC TX will pop

out next TPSR and TBCR1, 0

from TX Command Queue then

transmit this packet following

CSMA/CD protocol.

It is recommended to enable

this function to enhance TX

performance.

AX88796B will report Current of Transmit End Page

CTEPR (offset 1Ch) when every packet transmits

completed.

Host can understand AX88796B current of transmitting

buffer point by reading CTEPR.

MAC TX

function block

22

AX88796BLF / AX88796BLI

Transmit Packet Assembly

The AX88796B requires a contiguous assembled packet with the format shown below. The transmit byte count

includes the Destination Address, Source Address, Length Field and Data. It does not include preamble and CRC.

When transmitting data smaller than 64 bytes, AX88796B can auto padding to a minimum length of 64 bytes Ethernet

frame. The packets are placed in the buffer RAM by the system. System programs the AX88796B Core's Remote

DMA to move the data from the system buffer RAM to internal transmit buffer RAM.

The data transfer must be 16-bits (1 word) when in 16-bit mode, and 8-bits when the AX88796B Controller is set in

8-bit mode. The data width is selected by setting the WTS bit in the Data Configuration Register.

Destination Address

6 Bytes

Source Address

6 Bytes

Length / Type

2 Bytes

Data

(Pad if < 46 Bytes)

46 Bytes

Min.

General Transmit Packet Format

Transmission

Prior to transmission, the TPSR (Transmit Page Start Register) and TBCR0, TBCR1 (Transmit Byte Count

Registers) must be initialized. To initiate transmission of the packet the TXP bit in the Command Register is set. The

Transmit Status Register (TSR) is cleared and the AX88796B begins to pre-fetch transmit data from memory. If the

Inter-packet Gap (IPG) has timed out the AX88796B will begin transmission.

Conditions Required To Begin Transmission

In order to transmit a packet, the following three conditions must be met:

1. The Inter-packet Gap Timer has timed out

2. At least one byte has entered the FIFO.

3. If a collision had been detected then before transmission the packet back-off time must have timed out.

Collision Recovery

During transmission, the Buffer Management logic monitors the transmit circuitry to determine if a collision has

occurred. If a collision is detected, the Buffer Management logic will reset the FIFO and restore the Transmit DMA

pointers for retransmission of the packet. The COL bit will be set in the TSR and the NCR (Number of Collisions

Register) will be incremented. If 15 retransmissions each result in a collision the transmission will be aborted and the

ABT bit in the TSR will be set.

23

AX88796BLF / AX88796BLI

Transmit Packet Assembly Format

The following diagrams describe the format for how packets must be assembled prior to transmission for different

byte ordering schemes. The various formats are selected in the Data Configuration Register.

D15 D8 D7 D0

D[15:8]

D[7:0]

Destination Address 1

Destination Address 0

Destination Address 3

Destination Address 2

Destination Address 5

Destination Address 4

Source Address 1

Source Address 0

Source Address 3

Source Address 2

Source Address 5

Source Address 4

Type / Length 1

Type / Length 0

Data 1

Data 0

…

WTS = 1 in Data Configuration Register.

This format is used with ISA or 80186 Mode.

D7 D0

Destination Address 0 (DA0)

Destination Address 1 (DA1)

Destination Address 2 (DA2)

Destination Address 3 (DA3)

Destination Address 4 (DA4)

Destination Address 5 (DA5)

Source Address 0 (SA0)

Source Address 1 (SA1)

Source Address 2 (SA2)

Source Address 3 (SA3)

Source Address 4 (SA4)

Source Address 5 (SA5)

Type / Length 0

Type / Length 1

Data 0

Data 1

…

WTS = 0 in Data Configuration Register.

This format is used with ISA or MCS-51 Mode.

Note: All examples above will result in a transmission of a packet in order of DA0 (Destination Address 0), DA1,

DA2, DA3 and so on in byte. Bits within each byte will be transmitted least significant bit first.

24

AX88796BLF / AX88796BLI

4.2.3 Filling Packet to Transmit Buffer (Host fill data to memory)

The Remote DMA channel is used to both assembles packets for transmission, and to remove received packets from

the Receive Buffer Ring. It may also be used as a general-purpose slave DMA channel for moving blocks of data or

commands between host memory and local buffer memory. There are two modes of operation, Remote Write and

Remote Read Packet.

Two register pairs are used to control the Remote DMA, a Remote Start Address (RSAR0, RSAR1) and a Remote

Byte Count (RBCR0, RBCR1) register pair. The Start Address Register pair points to the beginning of the block to be

moved while the Byte Count Register pair is used to indicate the number of bytes to be transferred. Full handshake

logic is provided to move data between local buffer memory (Embedded Memory) and a bi-directional data port.

Remote Write

A Remote Write transfer is used to move a block of data from the host into local buffer memory. The Remote DMA

will read data from the I/O port and sequentially write it to local buffer memory beginning at the Remote Start

Address. The DMA Address will be incremented and the Byte Counter will be decremented after each transfer. The

DMA is terminated when the Remote Byte Count Register reaches a count of zero.

4.2.4 Removing Packets from the Ring (Host read data from memory)

Remote Read

A Remote Read transfer is used to move a block of data from local buffer memory to the host. The Remote DMA will

sequentially read data from the local buffer memory, beginning at the Remote Start Address, and write data to the I/O

port. The DMA Address will be incremented and the Byte Counter will be decremented after each transfer. The DMA

is terminated when the Remote Byte Count Register reaches zero.

Packets are removed from the ring using the Remote DMA or an external device. When using the Remote DMA. The

Boundary Pointer can also be moved manually by programming the Boundary Register. Care should be taken to keep

the Boundary Pointer at least one buffer behind the Current Page Pointer. The following is a suggested method for

maintaining the Receive Buffer Ring pointers.

1. At initialization set up a software variable (next_pkt) to indicate where the next packet will be read. At the

beginning of each Remote Read DMA operation, the value of next_pkt will be loaded into RSAR0 and RSAR1.

2. When initializing the AX88796B set:

BNRY = PSTART

CPR = PSTART + 1

next_pkt = PSTART + 1

3. After a packet is DMAed from the Receive Buffer Ring, the Next Page Pointer (second byte in AX88796B receive

packet buffer header) is used to update BNRY and next_pkt.

next_pkt = Next Page Pointer

BNRY = Next Page Pointer - 1

If BNRY < PSTART then BNRY = PSTOP – 1

Note the size of the Receive Buffer Ring is reduced by one 256-byte buffer; this will not, however, impede the

operation of the AX88796B. The advantage of this scheme is that it easily differentiates between buffer full and

buffer empty.

It is full when BNRY = CPR.

It is empty when BNRY = CPR-1.

25

AX88796BLF / AX88796BLI

Storage Format For Received Packets

The following diagrams describe the format for how received packets are placed into memory by the local DMA

channel. These modes are selected in the Data Configuration Register.

D15 D8 D7 D0

Next Packet Pointer

Receive Status

Receive Byte Count 1

Receive Byte Count 0

Destination Address 1

Destination Address 0

Destination Address 3

Destination Address 2

Destination Address 5

Destination Address 4

Source Address 1

Source Address 0

Source Address 3

Source Address 2

Source Address 5

Source Address 4

Type / Length 1

Type / Length 0

Data 1

Data 0

…

WTS = 1 in Data Configuration Register.

This format is used with ISA or 80186 Mode.

D7 D0

Receive Status

Next Packet Pointer

Receive Byte Count 0

Receive Byte Count 1

Destination Address 0

Destination Address 1

Destination Address 2

Destination Address 3

Destination Address 4

Destination Address 5

Source Address 0

Source Address 1

Source Address 2

Source Address 3

Source Address 4

Source Address 5

Type / Length 0

Type / Length 1

Data 0

Data 1

…

WTS = 0 in Data Configuration Register.

This format is used with ISA or MCS-51 Mode.

26

AX88796BLF / AX88796BLI

4.2.5 Other Useful Operations

Memory Diagnostics

Memory diagnostics can be achieved by Remote Write/Read DMA operations. The following is a suggested step for

memory test and assume the AX88796B has been well initialized.

1. Issue the STOP command to the AX88796B. This is accomplished be setting the STP bit in the AX88796B's

Command Register. Writing 21H to the Command Register will stop the AX88796B.

2. Wait for at least 1.5 ms. Since the AX88796B will complete any reception that is in progress, it is necessary to

time out for the maximum possible duration of an Ethernet reception. This action prevents buffer memory

from written data through Local DMA Write.

3. Write data pattern to MUT (memory under test) by Remote DMA write operation.

4. Read data pattern from MUT (memory under test) by Remote DMA read operation.

5. Compare the read data pattern with original write data pattern and check if it is equal.

6. Repeat step 3 to step 5 with various data pattern.

Loop-back Diagnostics

1. Issue the STOP command to the AX88796B. This is accomplished be setting the STP bit in the AX88796B's

Command Register. Writing 21h to the Command Register will stop the AX88796B.

2. Wait for at least 1.5 ms. Since the AX88796B will complete any reception that is in progress, it is necessary to

time out for the maximum possible duration of an Ethernet reception. This action prevents buffer memory

from written data through Local DMA Write.

3. Place the AX88796B in mode 1 loop-back. (MAC internal loop-back) This can be accomplished by setting

LB1 and LB0, of the Transmit Configuration Register to ``0,1''.

4. Issue the START command to the AX88796B. This can be accomplished by writing 22h to the Command

Register. This is necessary to activate the AX88796B's Remote DMA channel.

5. Write data that want to transmit to transmit buffer by Remote DMA write operation.

6. Issue the TXP command to the AX88796B. This can be accomplished by writing 26h to the Command

Register.

7. Read data current receive buffer by Remote DMA read operation.

8. Compare the received data with original transmit data and check if it is equal.

9. Repeat step 5 to step 8 for more packets test.

27

AX88796BLF / AX88796BLI

4.3 Wake-up Detection

Setting wake up Control and Status WUCS (CR page3, offset 0Ah) and D1 power saving in Power Management

Register PMR (CR page3, offset 0Bh), place the AX88796B in wake on LAN detection mode. In this mode, normal

data reception is disabled. And detection logic within the MAC examines receive data for three kinds of WOL events.

- Examines receive data for the pre-programmed wake-up frame patterns

- Examines receive data for the Magic Packet frame patterns

- Examines PHY link status change

4.3.1 Wake-up frame

AX88796B supports four programmable filters that support many different receive packet patterns. If the remote

wakeup mode is enable (in D1 sleep state). The remote wakeup function receives all frames and checks each frame

against the enabled filter and recognizes the frame as a remote wake-up frame if it passes the MAC address filtering

and CRC value match. In order to determine which bytes of the frames should be checked by the CRC-16 (x16 +x15

+x2 +1) module. AX88796B use a programmable byte mask and a programmable pattern offset for each of the four

supported filters. AX88796B also provide last byte match check and options cascade four programmable filters.

Make the four of detectors can operate simultaneously or sequentially.

The byte mask is a 32-bit field that specifies whether or not each of the 32 contiguous bytes within the frame,

beginning in the pattern offset, should be checked. If bit j in the byte mask is set, the diction logic checks byte offset

+j in the frame.

The pattern offset define on Offset 3 ~ 0 for each wake-up filter 3 ~ 0 and the real offset value equal to Offset register

multiplied by 2. (For example, The real offset value equal to 12 if set 6 on Offset register field)

Last bytes 3 ~ 0 for each wake-up filter 3 ~ 0 also. The contents of Last Byte register must equal to the last of Byte

Mask bit indicates of byte value. For example, if set Byte Mask [31:0] as 00C30003h then Byte Mask [23] is the last

byte. Thus, The contents of Last byte register must equal to byte value of offset + 23.

In order to load the 32-bits of wake up control register host driver software must perform 4 writes for every 32 bit of

registers.

The first write of 8-bit is located at [31:24]. The second write will also occupy [31:24] and shift the first write of data

to [23:16]. The first write of data will be located at [7:0] after continue 4 times of write data.

3

2

1

0

8 7 6 5 4 3 2 1 0

Byte Mask 0

Byte Mask 1

Byte Mask 2

Byte Mask 3

Wakeup Frame 1 CRC

Wakeup Frame 0 CRC

Wakeup Frame 3 CRC

Wakeup Frame 2 CRC

Offset 3

Offset 2

Offset 1

Offset 0

Last Byte 3

Last Byte 2

Last Byte 1

Last Byte 0

Reserved

Cascade

Command

[2:0]

Command 3

Command 2

Command 1

Command 0

Wake-Up frame Byte Mask Register Structure

4th

[31:24]

3rd

[23:16]

2nd

[15:8]

1st

[7:0]

28

AX88796BLF / AX88796BLI

.

For Example.

A Ping packet is configured as a Wakeup frame and AX88196B MAC address is 00 A0 0C C4 7D 69.

00 A0 0C C4 7D 69 00 0E C6 12 34 56 08 00 45 00

00 3C 01 8C 00 00 80 01 27 1E C0 09 C9 02 C0 09

C9 01 08 00 47 5C 05 00 01 00 61 62 63 64 65 66

67 68 69 6A 6B 6C 6D 6E 6F 70 71 72 73 74 75 76

77 61 62 63 64 65 66 67 68 69 CRC (4 bytes)

Host configure Wakeup frame registers sequences

// Go to gape3

Write CR(Offset 0h) C2h ; page3

// Set Byte Mask 0 = 00 40 08 07

Write WFBM0 (Page3, Offset 01H) 07h ; WFBM0 = 07 00 00 00h

Write WFBM0 (Page3, Offset 01H) 08h ; WFBM0 = 08 07 00 00h

Write WFBM0 (Page3, Offset 01H) 40h ; WFBM0 = 40 08 07 00h

Write WFBM0 (Page3, Offset 01H) 00h ; WFBM0 = 00 40 08 07h

// Set {Wakeup Frame 1 CRC, Wakeup Frame 0 CRC} = 00 00 2B 42h

Write WF10CRC (Offset 05H) 42h ; WF10CRC = 42 00 00 00h

Write WF10CRC (Offset 05H) 2Bh ; WF10CRC = 2B 42 00 00h

Write WF10CRC (Offset 05H) 00h ; WF10CRC = 00 2B 42 00h

Write WF10CRC (Offset 05H) 00h ; WF10CRC = 00 00 2B 42h

// Set {Offset 3 2 1 0} = 00 00 00 06h

Write WFOFST (Offset 07H) 06h ; WFOFST = 06 00 00 00h

Write WFOFST (Offset 07H) 00h ; WFOFST = 00 06 00 00h

Write WFOFST (Offset 07H) 00h ; WFOFST = 00 00 06 00h

Write WFOFST (Offset 07H) 00h ; WFOFST = 00 00 00 06h (Offset = 6*2 = 12)

// Set {Last Byte 3 2 1 0} = 00 00 00 08h

Write WFLB (Page3, Offset 08H) 08h ; {Last Byte 3 2 1 0} = 08 00 00 00h

Write WFLB (Page3, Offset 08H) 00h ; {Last Byte 3 2 1 0} = 00 08 00 00h

Write WFLB (Page3, Offset 08H) 00h ; {Last Byte 3 2 1 0} = 00 00 08 00h

Write WFLB (Page3, Offset 08H) 00h ; {Last Byte 3 2 1 0} = 00 00 00 08h

// Set {Cascade, Command 3 2 1 0} = 00 00 00 03h

Write WFCMD (Offset 09H) 03h ; WFCMD = 03 00 00 00h

Write WFCMD (Offset 09H) 00h ; WFCMD = 00 03 00 00h

Write WFCMD (Offset 09H) 00h ; WFCMD = 00 00 03 00h

Write WFCMD (Offset 09H) 00h ; WFCMD = 00 00 00 03h (enabled wake-up frame filter 0, and DA

match is required)

// Set PME and IRQ pin I/O Buffer Type (Please Ref. Datasheet Offset 15 descriptions)

Write BTCR (Offset 15H) ;

// Host enables wakeup frame detection then enter D1 sleep

Write WUCSR (Page3, Offset 0AH) 02h ; (Wakeup frame enable)

Write PMR (Offset 0BH) 01h ; (Enter D1 Sleep mode)

4.3.2 Magic Packet frame

AX88796B checks frame for 16 repetitions of the MAC address without any breaks or interruptions. The 16

repetitions may be anywhere in the frame but must be preceded by the synchronization stream

48‟hFF_FF_FF_FF_FF_FF pattern. If the MAC address of a node is 00h 11h 22h 33h 44h 55h, then AX88796B

scans for the following data sequence in an Ethernet frame.

Destination Address (6 byte) Source Address (6 byte) . . . . . . . . . FF FF FF FF FF FF

00 11 22 33 44 55 00 11 22 33 44 55 00 11 22 33 44 55 00 11 22 33 44 55

. . . . . . . . . CRC (4 byte)

29

AX88796BLF / AX88796BLI

4.4 Flow Control

The AX88796B supports Full-duplex flow control using the pause control frame. It also supports half-duplex flow

control using collision base of back-pressure method.

4.4.1 Full-Duplex Flow Control

The format of a PAUSE frame is illustrated below. It conforms to the standard Ethernet frame format but includes a

unique type field and other parameters as follows:

The destination address of the frame may be set to either the unique DA of the station to be paused, or to the globally

assigned multicast address 01-80-C2-00-00-01 (hex). The IEEE 802.3 standard for use in MAC control PAUSE

frames has reserved this multicast address. The "Type" field of the PAUSE frame is set to 88-08 (hex) to indicate the

frame is a MAC Control frame.

The MAC Control opcode field is set to 00-01 (hex) to indicate the type of MAC Control frame being used is a

PAUSE frame. The PAUSE frame is the only type of MAC Control frame currently defined.

The MAC Control Parameters field contains a 16-bit value that specifies the duration of the PAUSE event in units of

512-bit times. Valid values are 00-00 to FF-FF (hex). If an additional PAUSE frame arrives before the current

PAUSE time has expired, its parameter replaces the current PAUSE time, so a PAUSE frame with parameter zero

allows traffic to resume immediately.

A 42-byte reserved field (transmitted as all zeros) is required to pad the length of the PAUSE frame to the minimum

Ethernet frame size.

Preamble

(7-bytes)

Start Frame

Delimiter

(1-byte)

Dest. MAC

Address

(6-bytes)

= (01-80-C2-

00-00-01)

Source

MAC

Address

(6-bytes)

Length/Type

(2-bytes)

= 802.3 MAC

Control

(88-08)

MAC Control

Opcode

(2-bytes)

= PAUSE

(00-01)

MAC Control

Parameters

(2-bytes)

= (00-00 to

FF-FF)

Reserved

(42-bytes)

= all zeros

Frame

Check

Sequence

(4-bytes)

AX88796B will inhibit transmit frames for a specified period of time if a PAUSE frame received and CRC is correct.

If a PAUSE request is received while a transmit frame is in progress, then the pause will take effect after the

transmitting is completed.

AX88796B base on “Rx Page Start Register” (CR page0 Offset 01h) and “Rx Page Stop Register”(CR page0 Offset

02h) to calculate and got the total of free page count can be used for store received packets. (One page equal to 256

bytes) The total of free page count will decrease when packets received. A programmable of high water

free-page-count in “Flow Control Register” (Offset 1Ah) used to measure the water level of receive buffer.

AX88796B use XOFF / XON flow-control method to avoid missing packet if receive buffer almost full. A XON

transmitting when the total of free page count equal to or less then “high water free-page-count”. A XOFF

transmitting when the total of free page count equal to or greater then (“high water free-page-count” + 6 pages).

Fig - 6 TX / RX Flow control

RX

PAUSE frame

TX

HOST

Packet

STOP

AX88796B

TX Flow Control RX Flow Control

The total of

free pages count

Programmable of free-page-count

Start to generate XON

frame packet

generate XOFF frame

packet

High water mark

Low water mark

Packets in RX buffer

6 pages

30

AX88796BLF / AX88796BLI

4.4.2 Half-Duplex Flow Control

Whenever the receive buffer becomes full crosses a certain threshold level, The MAC starts sending a Jam signal,

which will result in a collision. After sensing the collision, the remote station will back off its transmit ion.

AX88796B only generate this collision-based of back-pressure when it receives a new frame, in order to avoid any

late collisions.

A programmable of “Back-pressure Jam Limit count” (Offset 17h) is used for avoid HUB port partition due to many

continues of collisions. AX88796B will reset the “Back-pressure Jam Limit count” when either a transmitted or

received frame without collision. A back-pressure leakage allow when senses continue of collisions count up to

“Back-pressure Jam Limit count”, it will be no jamming one of receive frame even receive buffer is full.

4.5 Big- and Little-endian Support

AX88796B supports “Big-“ or “Little-endian” processor. To support big-endian processors, the hardware designer

must explicitly invert the layout of the byte lanes. In addition, for a 16-bit interface, the big-endian register must be

set correctly following the table below.

Additionally, please refer to Big-endian register (offset 1Eh), for additional information on status indication on big-

or little-endian modes.

MODE OFOPERATION

AX88796B DATA PINS

DESCRIPTION

SD[15:8]

SD[7:0]

Mode 0 Big-endian register (offset 1Eh) “not” equal to 0x0000h

Even access

Byte3

Byte2

This mode can be used by 32-bit processors

operating with an external 16-bit bus.

Odd access

Byte1

Byte0

Mode 1 Big-endian register (offset 1Eh) equal to 0x0000h (default)

Even access

Byte1

Byte0

This mode can also be used by native 16-bit

processors.

Odd access

Byte3

Byte2

Tab - 11 Byte Lane Mapping

AX88796B‟s 16-bit Data Port (DP) read/write like a FIFO not rely on address pin. The “Even access” means the first

of access Data Port (DP) behind of remote read/write Command Register (CR). The second time access Data Port

(DP) is “Odd access” and then next is “Even access”, and so on.

Host can read bit-7 in “Device Status Register” (Offset 17h) to know the current of big- or little-endian types. The

default is Little-endian mode.

4.6 General Purpose Timer (GP Timer)

The programmable General Purpose Timer can be used to generate periodic host interrupts and the resolution of this

timer is 100us.

The GP timer is a 16-bit of register. GPT1 (CR page3 offset 0Fh) and GPT0 (CR page3 offset 0Eh) to compost this

16-bit of General Purpose Timer. This GP timer field of default value is FFFFh. Once set the General Purpose Timer

Enable (CR page3 Offset 0Dh) the GPT counts down until it reaches 0000h then update the a new pre-load value into

GPT, and continues counting.

The GPT interrupt has no status indicate in Interrupt Status Register (CR page0 offset 07h). The interrupt event will

keep active until host driver read Interrupt Status Register (CR page0 offset 07h) then clear GPT interrupt event.

31

AX88796BLF / AX88796BLI

4.7 EEPROM Interface

AX88796B can optionally load its MAC address from an external serial EEPROM. If a properly configured

EEPROM is detected by AX88796B at power-up, hard reset or host set a reload EEPROM request (CR page3 offset

0Ch), the constants of EEPROM data will be auto loading to internal memory from 0000h to 001Fh and from 0400h

to 040Fh automatically. It is similar NE2000 PROM store MAC address field. A detailed explanation of the

EEPROM data format in section 3.1 “EEPROM Memory Mapping”. After auto load EEPROM completed not

indicate AX88796B knew its MAC address. Host driver can get MAC address from internal memory (0000h ~

001Fh) or (0400h ~ 040Fh) and write “Physical Address Registers” (CR page1 offset 01h ~ 06h).

The AX88796B EEPROM use 3 PIN to connect to a most “93C46” type EEPROM configured for x16-bit operation.

A connect diagram as below

Fig - 7 EEPROM connections

After EEPROM loader has finished reading the MAC after power-on, hard reset or host set a reload EEPROM

request (CR page3 offset 0Ch), the Host is free to perform EECS, EECK and EEDIO as General Purpose I/O pin.

4.8 Power management

AX88796B supports power-down modes to allow applications to minimize power consumption. There is one normal

operation power state, D0 and there are two power saving states: D1, and D2. The “Power Management

Register”(CR Page3 Offset 0Bh) controls those of power management modes. In D1 power saving state, AX88796B

supports Wake on LAN function. In D2 power saving state, AX88796B will off all function block and clocks to

minimize power consumption. After wakeup event, the “Power Management Register” will be cleared and state at

normal operation power state. When AX88796B in either D1 or D2 power saving mode, host can write “Host Wake

Up Register” (Offset 1Fh) return the AX88796B to the D0 state. Power is reduced to various modules by disabling

the clocks as outlined in table as below.

AX88796B

BLOCK

D0

(Normal

operation)

D1

(WOL)

D2

Internal

clock

On

Off

MAC and

Host

On

Off

MAC power

management

On

Rx Block On

Off

PHY

On

Off

Tab - 12 Power Management Statuses

EECS

EECK

EEDIO

AX88796B

EECS

EECK

EEDI

EEDO

93C46

32

AX88796BLF / AX88796BLI

4.8.1 Power Management Event Indicators

The external PME signal can be setup as Push-Pull driver or open-drain buffer. And also can be set as active high or

active low. When set the PME_IND bit to a „1‟, (offset 15h) the external PME signal will be driven active for 60ms

upon detection of a wake-up event. When the PME_IND bit is cleared, the PME signal will be driven continuously

upon detection of a wake-up event. Host can checks which kind of wake-up event activity by reads “Wake up Control

and Status Register”(CR page3 offset 0Ah). Host can writing “Power Management Register”(CR page3 offset 0Bh)

or writing a „1‟ to clear wake-up event activity flags on “Wake up Control and Status Register”(CR page3 offset 0Ah)

to deactivated PME signal.

MPEN (CR page3 offset 0Ah)

ENB PME

logic

PME_POL (offset 15h)

PME_TYPE (offset 15h)

WUEN (CR page3 offset 0Ah)

Magic Packet Detect event

Wakeup Frame Detect event

ENB

logic

IREQ

IRQ_TYPE (offset 15h)

IRQ_POL (offset 15h)

System interrupt event

PME_IRQ_EN (offset 15h)

IRQ_TYPE (from EEPROM)

IRQ_POL (from EEPROM)

PME_IND (offset 15h)

60ms

Fig - 8 PME and IRQ signal generation

4.9 Device Ready or Busy

There are three kinds of device ready indicator in “Device Status Register” (Offset 17h). Those are indicates

AX88796B internal operation busy. In order to prevent the host access AX88796B in the busy stage, host can to

check the “Device Status Register” before doing some key operations.

When a “0” at the bit-4 (D-RDY) in “Device Status Register” (Offset 17h), indicate the AX88796B in reset state or

power saving state or EEPROM loading state or loop-back mode swapping.

When a “0” at the bit-5 (RD-RDY) in “Device Status Register” (Offset 17h), indicate the remote-DMA-read data not

ready yet, host must not read data port (DP) in this period. The non-ready period only happen when host set a

remote-read command on “Command Register”(CR), and it will be go to ready state when a valid data pop out for

host to reading. Host driver can back-to-back read data port (DP) since checked the RD-RDY was ready. The

maximum of remote-read non-ready period only spend 60ns. Host can ignore to check RD_RDY if host access time

not faster then it.

When a “0” at the bit-6 (RDMA-RDY) in “Device Status Register” (Offset 17h), indicate the remote DMA not

completed yet. This RDMA-RDY will be cleared when host write “Remote Byte Count 0” RBCR0 (CR page0 Offset

0Ah) or “Remote Byte Count 1” RBCR1 (CR page0 Offset 0Bh). The byte counter will down counting when every

data port (DP) access. This RDMA-RDY will be set when byte counter count to zero.

33

AX88796BLF / AX88796BLI

5.0 Registers Operation

5.1 MAC Control and Status Registers (CSR)

All registers of MAC Core are 8-bit wide except data port (DP). Data Port is optional 8 or 16-bit wide by WTS (DCR).

Offset 01h to 0Fh mapped into pages, which are selected by PS (Page Select) in the Command Register.

Offset

Page0

Page1

Page2

Page3

00H

Command Register (CR)

01H

02H

03H

04H

05H

06H

07H

08H

09H

0AH

0BH

0CH

0DH

0EH

0FH

10H, 11H

Data Port (DP)

12H

Inter-frame Gap Segment 1 (IFGS1)

13H

Inter-frame Gap Segment 2 (IFGS2)

14H

MII/EEPROM Access

15H

Buffer Type Configure Register (BTCR)

16H

Inter-frame Gap (IFG)

17H

Device Status Register (DSR) / Back-pressure Jam Limit Count (BJLC)

18H

Max Frame Size [7:0]

19H

Max Frame Size [11:8]

1AH

Flow Control Register (FCR)

1BH

MAC Configure Register (MCR)

1CH

Current TX End Page Register (CTEPR) / VLAN_ID_0

1DH

Reserved / VLAN_ID_1

1EH

Reserved / Big-Endian Register (BER)

1FH

Software Reset / Host Wake up (HWAKE)

Page0 of registers

Page1 of registers

Page2 of registers

Page3 of registers

34

AX88796BLF / AX88796BLI

PAGE 0 (PS1=0,PS0=0)

Offset

Read

Write

00H

Command Register (CR)

01H

Rx Page Start Register (PSTART)

Page Start Register (PSTART)

02H

Rx Page Stop Register (PSTOP)

Page Stop Register (PSTOP)

03H

Boundary Pointer (BNRY)

04H

Transmit Status Register (TSR)

Transmit Page Start Address (TPSR)

05H

Number of Collisions Register (NCR)

Transmit Byte Count Register 0 (TBCR0)

06H

Current Page Register (CPR)

Transmit Byte Count Register 1 (TBCR1)

07H

Interrupt Status Register (ISR)

08H

Current Remote DMA Address 0 (CRDA0)

Remote Start Address Register 0 (RSAR0)

09H

Current Remote DMA Address 1 (CRDA1)

Remote Start Address Register 1 (RSAR1)

0AH

Reserved

Remote Byte Count 0 (RBCR0)

0BH

Reserved

Remote Byte Count 1 (RBCR1)

0CH

Receive Status Register (RSR)

Receive Configuration Register (RCR)

0DH

Frame Alignment Error Tally Register

(CNTR0)

Transmit Configuration Register (TCR)

0EH

CRC Error Tally Register (CNTR1)

Data Configuration Register (DCR)

0FH

Frames Lost Tally Register (CNTR2)

Interrupt Mask Register (IMR)

11H, 10H

Data Port (DP)

12H

Inter-frame Gap Segment 1 (IFGS1)

13H

Inter-frame Gap Segment 2 (IFGS2)

14H

MII/EEPROM Access

15H

Buffer Type Configure Register (BTCR)

16H

Inter-frame Gap (IFG)

17H

Device Status Register (DSR)

Back-pressure Jam Limit count (BJLC)

18H

Max Frame Size [7:0]

19H

Max Frame Size [11:8]

1AH

Flow Control Register (FCR)

1BH

MAC Configure Register (MCR)

1CH

Current TX End Page Register (CTEPR)

VLAN_ID_0

1DH

Reserved

VLAN_ID_1

1EH

Reserved

Big-Endian Register (BER)

1FH

Software Reset

Host Wake up (HWAKE)

Tab - 13 Page 0 of MAC Core Registers Mapping

35

AX88796BLF / AX88796BLI

PAGE 1 (PS1=0,PS0=1)

Offset

Read

Write

01H

Physical Address Register 0

(PAR0)

Physical Address Register 0

(PAR0)

02H

Physical Address Register 1

(PAR1)

Physical Address Register 1

(PAR1)

03H

Physical Address Register 2

(PAR2)

Physical Address Register 2

(PAR2)

04H

Physical Address Register 3

(PAR3)

Physical Address Register 3

(PAR3)

05H

Physical Address Register 4

(PAR4)

Physical Address Register 4

(PAR4)

06H

Physical Address Register 5

(PAR5)

Physical Address Register 5

(PAR5)

07H

Current Page Register

(CPR)

Current Page Register

(CPR)

08H

Multicast Address Register 0

(MAR0)

Multicast Address Register 0

(MAR0)

09H

Multicast Address Register 1

(MAR1)

Multicast Address Register 1

(MAR1)

0AH

Multicast Address Register 2

(MAR2)

Multicast Address Register 2

(MAR2)

0BH

Multicast Address Register 3

(MAR3)

Multicast Address Register 3

(MAR3)

0CH

Multicast Address Register 4

(MAR4)

Multicast Address Register 4

(MAR4)

0DH

Multicast Address Register 5

(MAR5)

Multicast Address Register 5

(MAR5)

0EH

Multicast Address Register 6

(MAR6)

Multicast Address Register 6

(MAR6)

0FH

Multicast Address Register 7

(MAR7)

Multicast Address Register 7

(MAR7)

Tab - 14 Page 1 of MAC Core Registers Mapping

36

AX88796BLF / AX88796BLI

PAGE 2 (PS1=1,PS0=0)

Offset

Read

Write

01H

00h

Reserved

02H

Reserved

03H

Reserved

04H

Reserved

05H

Reserved

06H

Reserved

07H

Reserved

08H

Reserved

09H

Reserved

0AH

Total Receive Buffer Free Page (TFP)

Reserved

0BH

Chip version (00h)

Reserved

0CH

Receive Configuration Register (RCR)

Reserved

0DH

Transmit Configuration Register (TCR)

Reserved

0EH

Data Configuration Register (DCR)

Reserved

0FH

Interrupt Mask Register (IMR)

Reserved

Tab - 15 Page 2 of MAC Core Registers Mapping

37

AX88796BLF / AX88796BLI

PAGE 3 (PS1=1,PS0=1)

Offset

Read

Write

01H

00h

WFBM0

02H

Reserved

WFBM1

03H

Reserved

WFBM2

04H

Reserved

WFBM3

05H

Reserved

WF10CRC

06H

Reserved

WF32CRC

07H

Reserved

WFOFST

08H

Reserved

WFLB

09H

Reserved

WFCMD

0AH

WUCSR

0BH

PMR

0CH

Reserved

REER

0DH

MISC

0EH

GPT0

0FH

GPT1

Tab - 16 Page 3 of MAC Core Registers Mapping

38

AX88796BLF / AX88796BLI

5.1.1 Command Register (CR)

Offset 00H (Read/Write)

Field

Name

Description (Default = 21h)

7:6

PS1, PS0

PS1, PS0: Page Select

The two bits select which register‟s page is to be accessed.

It will be reset to default value when set PMR to D1 to D2 sleep state.

PS1 PS0

0 0 page 0 (default)

0 1 page 1

1 0 page 2

1 1 page 3

5:3

RD2,

RD1,

RD0

RD2, RD1, RD0: Remote DMA Command

These three encoded bits control operation of the Remote DMA channel. RD2 could be set to

abort any Remote DMA command in process. RD2 is reset by AX88796B when a Remote

DMA has been completed. The Remote Byte Count should be cleared when a Remote DMA

has been aborted. The Remote Start Address is not restored to the starting address if the

Remote DMA is aborted.

It will be reset to default value when set PMR to D1 to D2 sleep state.

RD2 RD1 RD0

0 0 0 Not allowed

0 0 1 Remote Read

0 1 0 Remote Write

0 1 1 Not allowed

1 X X Abort / Complete Remote DMA (default)

2

TXP

TXP: Transmit Packet

This bit could be set to initiate transmission of a packet

1

START

START:

This bit is used to active AX88796B operation.

This bit always read high when Host set once. It only clear by hardware or software reset.

0

STOP

STOP: Stop AX88796B

This bit is used to stop the AX88796B operation.

It will be reset to default value when set PMR to D1 to D2 sleep state.

39

AX88796BLF / AX88796BLI

5.1.2 Rx Page Start Register (PSTART)

Page0 Offset 01H (Read/Write)

Field

Name

Description (Default = 00h)

7:0

PSTART

Receive Buffer Ring Page Start Register

5.1.3 Rx Page Stop Register (PSTOP)

Page0 Offset 02H (Read/Write)

Field

Name

Description (Default = 00h)

7:0

PSTOP

Receive Buffer Ring Page Stop Register

5.1.4 Boundary Pointer (BNRY)

Page0 Offset 03H (Read/Write)

Field

Name

Description (Default = 4Ch)

7:0

BNRY

Boundary Page Pointer

5.1.5 Transmit Page Start Address (TPSR)

Page0 Offset 04H (Write)

Field

Name

Description

7:0

TPSR

Transmit Page Start Address

5.1.6 Transmit Status Register (TSR)

Page0 Offset 04H (Read)

Field

Name

Description (Default = 00h)

7

OWC

Out of window collision

6:4

-

Reserved

3

ABT

Transmit Aborted

Indicates the AX88796 aborted transmission because of excessive collision.

2

COL

Transmit Collided

Indicates that the transmission collided at least once with another station on the network.

1

-

Reserved

0

PTX

Packet Transmitted

Indicates transmission without error.

5.1.7 Transmit Byte Count Register (TBCR0)

Page0 Offset 05H (Write)

Field

Name

Description

7:0

TBCR0

Transmit Byte Count Register. The bit assignment is shown below

40

AX88796BLF / AX88796BLI

5.1.8 Number Of Collisions Register (NCR)

Page0 Offset 05H (Read)

Field

Name

Description (Default = 00h)

7:4

-

Always zero

3:0

NCR

If no collisions are experienced during a transmission attempt, the COL bit of the TSR will

not be set and the contents of NCR will be zero. If there are excessive collisions, the ABT bit

in the TSR will be set and the contents of NCR will be zero. The NCR is cleared after the

TXP bit in the CR is set.

5.1.9 Transmit Byte Count Register (TBCR1)

Page0 Offset 06H (Write)

Field

Name

Description

7:0

TBCR1

Transmit Byte Count Register.

5.1.10 Current Page Register (CPR)

Page0 Offset 06H (Read)

Field

Name

Description (Default = 4Dh)

7:0

CPR

The Buffer Management Logic as a backup register for reception uses this register internally.

CURR contains the address of the first buffer to be used for a packet reception and is used to

restore DMA pointers in the event of receive errors. This register is initialized to the same

value as PSTART and should not be written to again unless the controller is Reset.

5.1.11 Interrupt Status Register (ISR)

Page0 Offset 07H (Read/Write)

Field

Name

Description (Default = 80h)

7

RST

Reset Status:

Set when AX88796B enters reset state (or a wake-up event) and cleared when a start

command is issued to the CR. Writing to this bit is no effect.

6

RDC

Remote DMA Complete

Set when remote DMA operation has been completed. Write this bit to high then reset it.

5

CNT

Counter Overflow

Set when MSB of one or more of the Tally Counters has been set. Read CNTR0~CNTR2

registers to reset the Tally Counters and then write this bit to high then reset it.

4

OVW

OVERWRITE: Set when receive buffer ring storage resources have been exhausted.