KSZ8851-16/32MQL/MQLI
Single-Port Ethernet MAC Controller
with 8/16-Bit or 32-Bit Non-PCI Interface
Rev. 2.0
LinkMD is a registered trademark of Mic rel, Inc.
Magic Packet is a tradem ark of Advanced Micro Devices, Inc. Product names used in this datasheet are for identification purposes
only and may be trademarks of their respective companies.
Micrel Inc. • 2180 Fort une Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http:// www.mic rel .c om
August 2009 M9999-083109-2.0
General Description
The KSZ8851M-series is a single-port controller chip with
a non-PCI CPU interface and is available in 8/16-bit and
32-bit bus designs. This datasheet describes the 128-pin
PQFP KSZ8851-16/ 32MQL f or applicat ions requir ing high-
performance from single-port Ethernet Controller with
8/16-bit or 32-bit generic processor interface. The
KSZ8851M offers the most cost-effective solution for
adding high-throughput Ethernet connectivity to traditional
embedded systems.
The KSZ8851M is a single chip, mixed analog/digital
device offering Wake-on-LAN technology for effectively
addressin g Fast Ether net a pplicati ons. It consis ts of a Fas t
Ethernet MAC c ontro ller, a n 8-b it, 16-bi t and 3 2-bit gener ic
host processor interface and incorporates a unique
dynamic memory pointer with 4-byte buffer boundary and
a fully utilizable 18KB for both TX (allocated 6KB) and RX
(allocated 12KB) directions in host buffer interface.
The KSZ8851M is designed to be fully compliant with the
appropriate IEEE 802.3 standards. An industrial
temperature-grade version of the KSZ8851M, the
KSZ8851 MQLI is als o ava ilable ( see “O rderi ng Inf ormatio n
section).
LinkMD®
Physical signal transmission and reception are enhanced
through the use of analog circuitry, making the design
more efficient and allowing for lower-power consumption.
The KSZ8851M is designed using a low-power CMOS
process that features a single 3.3V power supply with
options for 1.8V, 2.5V or 3.3V VDD I/O. The device
includes an extensive feature set that offers management
information base (MIB) counters and CPU control/data
interfaces with single bus timing.
The KSZ8851M includes unique cable diagnostics feature
called LinkMD®. This feature determines the length of the
cabling plant and also ascertains if there is an open or
short condition in the cable. Accompanying software
enables the cable length and cable conditions to be
conveniently displayed. In addition, the KSZ8851M
supports Hewlett Packard (HP) Auto-MDIX thereby
eliminating the need to differentiate between straight or
crossover cables in applications.
Functional Diagram
Figure 1. KSZ8851-16/32MQL/MQLI Functional Diagram
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Features
Integrated MA C and PH Y Ethernet Control ler fully
complian t with IEE E 802. 3/ 802. 3u sta ndar ds
Designed for high performance and high throughput
applications
Supports 10BASE-T/100BASE-TX
Supports IEEE 802.3x full-duplex flow control and half-
duplex backpressure collision flow control
Supports DMA-s la ve burst data read and wr ite transf er s
Supports IP Header (IPv4)/TCP/UDP/ICMP checksum
generation and checking
Supports IPv6 TCP/UDP/ICMP checksum generation
and checking
Automatic 32-bit CRC generation and checking
Simple SRAM-like host interface easily connects to
most common embedded MCUs.
Supports multiple data frames for transmit and receive
without addres s bus and b yte-ena ble sign als
Supports both Big- and Little-Endian processors
Larger internal memory with 12K Bytes for RX FIFO and
6K Bytes for TX FIFO. Programmable low, high and
overrun wat ermark for flow control in RX FIFO
Efficient architecture design with configurable host
interrupt schemes to minimize host CPU overhead and
utilization
Powerful and flexible address filtering scheme
Optional to use external serial EEPROM configuration
for both KSZ8851-16MQL and KSZ8851-32MQL
Single 25 MHz reference clock for both PHY and MAC
HBM ESD Rating 6kV
Power Modes, Power Supplies, and Packaging
Single 3.3V power supply with options for 1.8V, 2.5V
and 3.3V VDD I/O
Built-in integrated 3.3V or 2.5V to 1.8V low noise
regulator for core and analog blocks
Enhanced power management feature with energy
detect mode and power-down mode to ensure low-
power dissipation during device idle periods
Comprehensive LED indicator support for link, activity,
full/half duplex, and 10/100 speed (4 LEDs)
– User programmable
Low-power CMOS design
Commercial Temperature Range: 0oC to +70oC
Industrial Temperature Range: –40oC to +85oC
Flexible package options available in 128-pin PQFP
KSZ8851-16/32MQ L or 48-pin LQ FP KSZ885 1-16M LL
Pin compatible with existing KSZ8841-16/32MQL and
KSZ8842-16/32MQ L in 128 - pin
Additional Features
In addition to offering all of the features of a Layer 2
controller , the KSZ8 851-16/ 32MQL of fers :
Flexible 8-bit, 16-bit and 32-bit generic host processor
interfaces with same access time and single bus timing
to any I/O registers and RX/TX FIFO buffers
Supports to add two-byte before frame header in order
for IP fram e content with doubl e word bou ndary
Micrel LinkMD® cable diagnostic capabilities to
determine cable length, diagnose faulty cables, and
determine distance to fault
Wake-on-LAN functionality
– Incorporates Magic Packet™, network link state, and
wake-up frame technology
HP Auto MDI-X™ crossover with disable/enable option
Ability to transmit and receive frames up to 2000 bytes
Network Features
10BASE-T and 100BASE-TX physical layer support
Auto-neg oti ati on: 10/1 00 M bps f ull and ha lf duplex
Adaptive equalizer
Baseline wander correction
Applications
Video/Audio Distribution Systems
High-end Cable, Satellite, and IP set-top boxes
Video over IP and IPTV
Voice over IP (VoIP) and Analog Telephone Adapters
(ATA)
Industrial Control in Latency Critical Applications
Home Base Stati on with Et her net Con necti on
Industrial Control Sensor Devices (Temperature,
Pressure, Levels, and Valves)
Security, Motion Control and Surveillance Cameras
Markets
Fast Ethernet
Embedded Ethernet
Industrial Ethernet
Embedded Systems
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Ordering Information
Part Number Temperature Range Package Lead Free
KSZ8851-16MQL 0ºC to 70ºC 128-Pin PQFP Pb-Free
KSZ8851-32MQL 0ºC to 70ºC 128-Pin PQFP Pb-Free
KSZ8851-16MQLI –40ºC to +85ºC 128-Pin PQFP Pb-Free
KSZ8851-32MQLI –40ºC to +85ºC 128-Pin PQFP Pb-Free
KSZ8851-16MQL-Eval Evaluation Board for the KSZ8851-16MQL
Revision History
Revision Date Summary of Changes
1.0 6/30/2008 First released Information.
1.1 2/13/2009 Improved EDS Rating up to 6KV, revised Ordering Information and Updated Table content
and description.
2.0 8/31/2009 Change revision ID from “0” to “1” in CIDER (0xc0) register. Update pins 24, 38, 43, 57, 63
and 91 description for 1.8V VDD_IO supply.
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Contents
Pin Configuration for 16-Bit...............................................................................................................................................10
Pin Description for 16-Bit...................................................................................................................................................11
Pin Configuration for 32-Bit...............................................................................................................................................16
Pin Description for 32-Bit...................................................................................................................................................17
Strapping Options...............................................................................................................................................................21
Functional Description.......................................................................................................................................................22
Functional Overview...........................................................................................................................................................22
Power Management........................................................................................................................................................22
Normal Operation Mode .................................................................................................................................................22
Energy Detect Mode.......................................................................................................................................................22
Soft Power Down Mode..................................................................................................................................................23
Power Saving Mode........................................................................................................................................................23
Power Down ...................................................................................................................................................................23
Wake-on-LAN.......................................................................................................................................................................23
Detection of Energy........................................................................................................................................................23
Detection of Linkup.........................................................................................................................................................24
Wake-up Packet .............................................................................................................................................................24
Magic Packet™...............................................................................................................................................................24
Physical Layer Transceiver (PHY).....................................................................................................................................24
100BASE-TX Transmit...................................................................................................................................................24
100BASE-TX Receive ....................................................................................................................................................25
PLL Clock Synthesizer (Recovery).................................................................................................................................25
Scrambler/De-scrambler (100BASE-TX only)................................................................................................................25
10BASE-T Transmit........................................................................................................................................................25
10BASE-T Receive.........................................................................................................................................................25
MDI/MDI-X Auto Crossover............................................................................................................................................25
Straight Cable ..........................................................................................................................................................26
Crossover Cable ......................................................................................................................................................26
Auto Negotiation.............................................................................................................................................................27
LinkMD® Cable Diagnostics............................................................................................................................................28
Access......................................................................................................................................................................28
Usage.......................................................................................................................................................................28
Med ia Access Contro l (MAC) Ope rat ion...........................................................................................................................29
Inter Packet Gap (IPG)...................................................................................................................................................29
Back-Off Algorithm..........................................................................................................................................................29
Late Collision ..................................................................................................................................................................29
Flow Control....................................................................................................................................................................29
Half-Duplex Backpressure..............................................................................................................................................29
Address Filtering Function..............................................................................................................................................30
Clock Generator..............................................................................................................................................................31
Bus Interface Unit (BIU)......................................................................................................................................................31
Supported Transfers.......................................................................................................................................................31
Physical Data Bus Size ..................................................................................................................................................31
Little and Big Endian Support.........................................................................................................................................32
Asynchronous Interface..................................................................................................................................................32
BIU Summation...............................................................................................................................................................32
Queue Management Unit (QMU)........................................................................................................................................33
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Transmit Queue (TXQ) Frame Format...........................................................................................................................33
Frame Transmitting Path Operation in TXQ...................................................................................................................34
Driver Routine for Transmit Packet from Host Processor to KSZ8851M.......................................................................35
Receive Queue (RXQ) Frame Format............................................................................................................................38
Frame Receiving Path Operation in RXQ.......................................................................................................................38
Driver Routine for Receive Packet from KSZ8851M to Host Processor ........................................................................39
EEPROM Interface...............................................................................................................................................................40
Loopback Support...........................................................................................................................................................41
Near-end (Remote) Loopback........................................................................................................................................41
Far-end (Local) Loopback ..............................................................................................................................................41
CPU Interface I/O Registers ...............................................................................................................................................42
I/O Registers...................................................................................................................................................................42
Internal I/O Registers Space Mapping............................................................................................................................43
Register Map: M AC, PHY and QMU...................................................................................................................................49
Bit Type Definition...........................................................................................................................................................49
0x00 – 0x05: Reserved...................................................................................................................................................49
Bus Error Status Register (0x06 – 0x07): BESR............................................................................................................49
Chip Configuration Register (0x08 – 0x09): CCR ..........................................................................................................49
0x0A – 0x0F: Reserved..................................................................................................................................................50
Host MAC Address Registers: MARL, MARM and MARH.............................................................................................50
Host MAC Address Register Low (0x10 – 0x11): MARL................................................................................................50
Host MAC Address Register Middle (0x12 – 0x13): MARM...........................................................................................50
Host MAC Address Register High (0x14 – 0x15): MARH ..............................................................................................50
0x16 – 0x1F: Reserved ..................................................................................................................................................51
On-Chip Bus Control Register (0x20 – 0x21): OBCR ....................................................................................................51
EEPROM Control Register (0x22 – 0x23): EEPCR .......................................................................................................51
Memory BIST Info Register (0x24 – 0x25): MBIR..........................................................................................................52
Global Reset Register (0x26 – 0x27): GRR ...................................................................................................................52
0x28 – 0x29: Reserved...................................................................................................................................................52
Wakeup Frame Control Register (0x2A – 0x2B): WFCR...............................................................................................52
0x2C – 0x2F: Reserved..................................................................................................................................................53
Wakeup Frame 0 CRC0 Register (0x30 – 0x31): WF0CRC0........................................................................................53
Wakeup Frame 0 CRC1 Register (0x32 – 0x33): WF0CRC1........................................................................................53
Wakeup Frame 0 Byte Mask 0 Register (0x34 – 0x35): WF0BM0 ................................................................................53
Wakeup Frame 0 Byte Mask 1 Register (0x36 – 0x37): WF0BM1 ................................................................................54
Wakeup Frame 0 Byte Mask 2 Register (0x38 – 0x39): WF0BM2 ................................................................................54
Wakeup Frame 0 Byte Mask 3 Register (0x3A – 0x3B): WF0BM3................................................................................54
0x3C – 0x3F: Reserved..................................................................................................................................................54
Wakeup Frame 1 CRC0 Register (0x40 – 0x41): WF1CRC0........................................................................................54
Wakeup Frame 1 CRC1 Register (0x42 – 0x43): WF1CRC1........................................................................................54
Wakeup Frame 1 Byte Mask 0 Register (0x44 – 0x45): WF1BM0 ................................................................................54
Wakeup Frame 1 Byte Mask 1 Register (0x46 – 0x47): WF1BM1 ................................................................................55
Wakeup Frame 1 Byte Mask 2 Register (0x48 – 0x49): WF1BM2 ................................................................................55
Wakeup Frame 1 Byte Mask 3 Register (0x4A – 0x4B): WF1BM3................................................................................55
0x4C – 0x4F: Reserved..................................................................................................................................................55
Wakeup Frame 2 CRC0 Register (0x50 – 0x51): WF2CRC0........................................................................................55
Wakeup Frame 2 CRC1 Register (0x52 – 0x53): WF2CRC1........................................................................................55
Wakeup Frame 2 Byte Mask 0 Register (0x54 – 0x55): WF2BM0 ................................................................................55
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Wakeup Frame 2 Byte Mask 1 Register (0x56 – 0x57): WF2BM1 ................................................................................56
Wakeup Frame 2 Byte Mask 2 Register (0x58 – 0x59): WF2BM2 ................................................................................56
Wakeup Frame 2 Byte Mask 3 Register (0x5A – 0x5B): WF2BM3................................................................................56
0x5C – 0x5F: Reserved..................................................................................................................................................56
Wakeup Frame 3 CRC0 Register (0x60 – 0x61): WF3CRC0........................................................................................56
Wakeup Frame 3 CRC1 Register (0x62 – 0x63): WF3CRC1........................................................................................56
Wakeup Frame 3 Byte Mask 0 Register (0x64 – 0x65): WF3BM0 ................................................................................56
Wakeup Frame 3 Byte Mask 1 Register (0x66 – 0x67): WF3BM1 ................................................................................56
Wakeup Frame 3 Byte Mask 2 Register (0x68 – 0x69): WF3BM2 ................................................................................57
Wakeup Frame 3 Byte Mask 3 Register (0x6A – 0x6B): WF3BM3................................................................................57
0x6C – 0x6F: Reserved..................................................................................................................................................57
Transmit Control Register (0x70 – 0x71): TXCR............................................................................................................57
Transmit Status Register (0x72 – 0x73): TXSR .............................................................................................................58
Receive Control Register 1 (0x74 – 0x75): RXCR1.......................................................................................................58
Receive Control Register 2 (0x76 – 0x77): RXCR2.......................................................................................................59
TXQ Memory Information Register (0x78 – 0x79): TXMIR ............................................................................................60
0x7A – 0x7B: Reserved..................................................................................................................................................60
Receive Frame Header Status Register (0x7C – 0x7D): RXFHSR ...............................................................................60
Receive Frame Header Byte Count Register (0x7E – 0x7F): RXFHBCR......................................................................61
TXQ Command Register (0x80 – 0x81): TXQCR ..........................................................................................................61
RXQ Command Register (0x82 – 0x83): RXQCR..........................................................................................................61
TX Frame Data Pointer Register (0x84 – 0x85): TXFDPR.............................................................................................62
RX Frame Data Pointer Register (0x86 – 0x87): RXFDPR............................................................................................63
0x88 – 0x8B: Reserved ..................................................................................................................................................63
RX Duration Timer Threshold Register (0x8C – 0x8D): RXDTTR .................................................................................63
RX Data Byte Count Threshold Register (0x8E – 0x8F): RXDBCTR ............................................................................64
Interrupt Enable Register (0x90 – 0x91): IER ................................................................................................................64
Interrupt Status Register (0x92 – 0x93): ISR .................................................................................................................65
0x94 – 0x9B: Reserved ..................................................................................................................................................66
RX Frame Count & Threshold Register (0x9C – 0x9D): RXFCTR.................................................................................66
TX Next Total Frames Size Register (0x9E – 0x9F): TXNTFSR ...................................................................................66
MAC Address Hash Table Register 0 (0xA0 – 0xA1): MAHTR0....................................................................................66
MAC Address Hash Table Register 1 (0xA2 – 0xA3): MAHTR1....................................................................................66
MAC Address Hash Table Register 2 (0xA4 – 0xA5): MAHTR2....................................................................................67
MAC Address Hash Table Register 3 (0xA6 – 0xA7): MAHTR3....................................................................................67
0xA8 – 0xAF: Reserved..................................................................................................................................................67
Flow Control Low Watermark Register (0xB0 – 0xB1): FCLWR....................................................................................67
Flow Control High Watermark Register (0xB2 – 0xB3): FCHWR...................................................................................67
Flow Control Overrun Watermark Register (0xB4 – 0xB5): FCOWR.............................................................................67
0xB6 – 0xBF: Reserved..................................................................................................................................................68
Chip ID and Enable Register (0xC0 – 0xC1): CIDER ....................................................................................................68
0xC2 – 0xC5: Reserved .................................................................................................................................................68
Chip Global Control Register (0xC6 – 0xC7): CGCR.....................................................................................................68
Indirect Access Control Register (0xC8 – 0xC9): IACR.................................................................................................68
0xCA – 0xCF: Reserved.................................................................................................................................................69
Indirect Access Data Low Regist er (0xD0 – 0xD1): IADLR ............................................................................................69
Indirect Access Data High Register (0xD2 – 0xD3): IADHR..........................................................................................69
Power Management Event Control Register (0xD4 – 0xD5): PMECR........................................................................... 69
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Go-Sleep & Wake-Up Time Register (0xD6 – 0xD7): GSWUTR...................................................................................70
PHY Reset Register (0xD8 – 0xD9): PHYRR ................................................................................................................70
0xDA – 0xDF: Reserved.................................................................................................................................................71
0xE0 – 0xE3: Reserved..................................................................................................................................................71
PHY 1 MII-Register Basic Control Register (0xE4 – 0xE5): P1MBCR...........................................................................71
PHY 1 MII-Register Basic Status Register (0xE6 – 0xE7): P1MBSR ............................................................................72
PHY 1 PHY ID Low Register (0xE8 – 0xE9): PHY1ILR.................................................................................................72
PHY 1 PHY ID High Register (0xEA – 0xEB): PHY1IHR...............................................................................................72
PHY 1 Auto-Negotia tio n Ad vertis ement Register (0xEC – 0xED): P1ANAR.................................................................73
PHY 1 Auto-Negotiation Link Partner Ability Register (0xEE – 0xEF): P1ANLPR.........................................................73
0xF0 – 0xF3: Reserved ..................................................................................................................................................74
Port 1 PHY Special Control/Status, LinkMD® (0xF4 – 0xF5): P1SCLMD ...................................................................... 74
Port 1 Control Register (0xF6 – 0xF7): P1CR................................................................................................................74
Port 1 Status Register (0xF8 – 0xF9): P1SR .................................................................................................................76
0xFA – 0xFF: Reserved..................................................................................................................................................76
MIB (Management Information Base) Counters...............................................................................................................77
Additional MIB Information .............................................................................................................................................78
Absolute Maximum Ratings...............................................................................................................................................79
Operating Ratings...............................................................................................................................................................79
Electrical Characteristics...................................................................................................................................................79
Timing Specifications.........................................................................................................................................................81
Asynchronous Read and Write Timing...........................................................................................................................81
Address Latching Timing for All Modes..........................................................................................................................82
Auto Negotiation Timing .................................................................................................................................................83
Reset Timing...................................................................................................................................................................84
EEPROM Timing ............................................................................................................................................................85
Selection of Isolation Transformers..................................................................................................................................86
Selection of Reference Crystal..........................................................................................................................................86
Package Inf ormat ion...........................................................................................................................................................87
Acronyms and Glossary.....................................................................................................................................................88
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List of Figures
Figure 1. KSZ8851-16/3 2M QL/ MQLI Functional Diagram .....................................................................................................1
Figure 2.128-Pin PQFP for 16-B it.........................................................................................................................................10
Figure 3.128-Pin PQFP for 32-B it.........................................................................................................................................16
Figure 4. Typica l Straight Cable Connection .......................................................................................................................26
Figure 5. Typical Crossover Cable Connection ...................................................................................................................27
Figure 6. Auto Negot iat ion and Para ll el Operation ..............................................................................................................28
Figure 7. KSZ8851M 8- Bit , 16-B it, and 32-Bit Data Bus Connec tio ns ................................................................................33
Figure 8. Host TX Single Frame in Manual Enqueue Flow Diagram ...................................................................................36
Figure 9. Host TX Multiple Frames in Auto- Enqueue Flow Diagram ..................................................................................37
Figure 10. Host RX Single or Multiple Frames in Auto-Dequeue Flow Diagram .................................................................39
Figure 11. PHY Port 1 Near- end (Remote) and Host Far-end (Local) Loopback Paths ......................................................41
Figure 12. Asynchrono us C ycle ...........................................................................................................................................81
Figure 13. Address Latching Cycle for All Modes ................................................................................................................82
Figure 14. Auto Negot iat io n Tim ing .....................................................................................................................................83
Figure 15. Reset Tim ing .......................................................................................................................................................84
Figure 16. EEPRO M Read C ycle Timing Diagram ..............................................................................................................85
Figure 17. 128-Pi n PQFP Package ......................................................................................................................................87
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List of Tables
Table 1. Internal Func ti on Blocks Status ............................................................................................................................. 22
Table 2. MDI/MDI-X Pin Definitions ..................................................................................................................................... 26
Table 3. Address Filtering Scheme...................................................................................................................................... 31
Table 4. Bus Interface Unit Sig na l Group in g........................................................................................................................ 32
Table 5. Frame Format for Transmit Queue ........................................................................................................................ 33
Table 6. Transmit Control Word Bit Fields........................................................................................................................... 34
Table 7. Transmit Byte Count Format.................................................................................................................................. 34
Table 8. Registers Setting for Transmit Function Block....................................................................................................... 35
Table 9. Frame Format for Receive Queue......................................................................................................................... 38
Table 10. Registers Setting for Receive Function Block...................................................................................................... 38
Table 11. KSZ8851M EEPROM Format.............................................................................................................................. 40
Table 12. ConfigParam Word in EEPROM Format.............................................................................................................. 40
Table 13. Format of MIB Counters....................................................................................................................................... 77
Table 14. Port 1 MIB Counters Indirect Memory Offsets..................................................................................................... 78
Table 15. Electrical Characteristics...................................................................................................................................... 80
Table 16. Asynchronous Cycle Timing Parameters............................................................................................................. 81
Table 17. Address Latching Timing Parameters.................................................................................................................. 82
Table 18. Auto Negotiation Timing Parameters................................................................................................................... 83
Table 19. Reset Timing Parameters .................................................................................................................................... 84
Table 20. EEPROM Timing Parameters.............................................................................................................................. 85
Table 21. Transformer Selection Criteria............................................................................................................................. 86
Table 22. Qualified Single Port Magnetic s........................................................................................................................... 86
Table 23. Typical Reference Crystal Characteristics........................................................................................................... 86
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Pin Configuration for 16-Bit
Figure 2. 128-Pin PQFP for 16-Bit
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Pin Description for 16-Bit
Pin Number Pin Name Type Pin Function
1 TEST_EN Ipd Test Enable
For normal operation, open or pull-down this pin to ground.
2 SCAN_EN Ipd Scan Test Scan Mux Enable
For normal operation, open or pull-down this pin to ground.
3 P1LED2 Opu
4 P1LED1 Ipu/O
5 P1LED0 Ipu/O
Port 1 LED indicators1 def ine d as follow s:
LED is ON when output is LOW; LED is OFF when output is HIGH.
Chip Global Control Register: CGCR
bit [15,9]
[0,0] Default [0,1]
P1LED32
P1LED2 Link/Act 100Link/Act
P1LED1 Full duplex/Col 10Link/Act
P1LED0 Speed Full duplex
Reg. CGCR bit [15,9]
[1,0] [1,1]
P1LED32 Act
P1LED2 Link
P1LED1 Full duplex/Col
P1LED0 Speed
Notes:
1. Link = On; Activity = Blink; Link/Act = On/Blink; Full Dup/Col = On/Blink;
Full Duplex = On (Full duplex); Off (Half duplex)
Speed = On (100BASE-T); Off (10BASE-T)
2. P1LED3 is pin 27.
6 NC No Connect.
7 NC No Connect.
8 NC No Connect.
9 DGND Gnd Digital ground
10 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
11 NC No Connect.
12 NC No Connect.
13 NC No Connect.
14 PME Ipu/O Power Management Event: It is asserted (low or high depends on polarity set in PMECR
register) when one of the wake-on-LAN events is detected by KSZ8851M. The
KSZ8851M is requesting the system to wake up from low power mode.
15 NC No Connect.
16 INTRN Opu Interrupt
Active Low signal to host CPU to indicate an interrupt status bit is set.
17 LDEVN Opu Local Device Not
Active Low output signal, asserted when AEN is Low and A7-A1 decode to the
KSZ8851M right address register. LDEVN is a combinational decode of the Address and
AEN signal.
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Pin Number Pin Name Type Pin Function
18 RDN Ipu Read Strobe Not
Asynchronous read strobe, active Low.
19 EECS Opd EEPROM Chip Select
This signal is used to select an external EEPROM device.
20 ARDY Opu Asynchronous Ready
ARDY may be used when interfacing asynchronous buses to extend bus access cycles. It
is asynchronous to the host CPU or bus clock. This pin need an external 4.7K pull-up
resistor.
21 NC No Connect.
22 NC No Connect
23 DGND Gnd Digital IO ground
24 VDDCO P 1.8V regulator output . This 1.8V output pin provides power to pins 38, 43, 57 (VDDA), 63
(VDDAP) and 91 (VDDC) for core VDD supply.
If VDD_IO is set for 1.8V then this pin should be left floating, pins 38, 43, 57 (VDDA), 63
(VDDAP) and 91 (VDDC) will be sourced by the external 1.8V supply that is tied to pins
10, 79, 92, 108 and 125 (VDDIO) with appropriate filtering.
25 NC No Connect.
26 EEEN Ipd EEPROM Enable
EEPROM is enabled and connected when this pin is pull-up.
EEPROM is disabled when this pin is pull-down or no connect.
27 P1LED3 Opd Port 1 LED indicator
See the description in pins 3, 4, and 5.
28 EEDO Opd EEPROM Data Out
This pin is connected to DI input of the serial EEPROM.
29 EESK Ipd/O
EEPROM Serial Clock: A 4μs (OBCR[1:0]=11 on-chip bus speed @ 25MHz) or 800ns
(OBCR[1:0]=00 on-chip bus speed @ 125MHz) serial output clock cycle to load
configuration data from the serial EEPROM.
Config Mode: The pull-up/pull-down value is latched as big or little endian mode during
power-up / reset. See “Strapping Options” section for details
30 EEDI Ipd EEPROM Data In
This pin is connected to DO output of the serial EEPROM when EEEN is pull-up.
This pin has to pull-down for 8-bit bus mode or pull-up for 16-bus mode when the EEEN
pin is pull-down (without EEPROM).
Config Mode: The pull-up/pull-down value is latched as 16- or 8-bit mode during power-up
/ reset. See “Strapping Options” section for details.
31 NC No Connect.
32 AEN Ipu Address Enable
Address and chip select qualifier for the address decoding and chip enable, active Low.
33 WRN Ipu Write Strobe Not
Asynchronous write strobe, active Low.
34 DGND Gnd Digital IO ground
35 NC No Connect.
36 PWRDN Ipu Full-chip power-down. Active Low (Low = Power down; High or floating = Normal
operation). All I/O pins will tri-state during chip power down.
37 AGND Gnd Analog ground
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Pin Number Pin Name Type Pin Function
38 VDDA P 1.8V analog power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
39 AGND Gnd Analog ground
40 NC No Connect
41 NC No Connect
42 AGND Gnd Analog ground
43 VDDA P 1.8V analog power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
44 NC No Connect
45 RXP1 I/O Port 1 physical receive (MDI) or transmit (MDIX) signal (+ differential)
46 RXM1 I/O Port 1 physical receive (MDI) or transmit (MDIX) signal (– differential)
47 AGND Gnd Analog ground
48 TXP1 I/O Port 1 physical transmit (MDI) or receive (MDIX) signal (+ differential)
49 TXM1 I/O Port 1 physical transmit (MDI) or receive (MDIX) signal (– differential)
50 VDDATX P 3.3V analog VDD input power supply with well decoupling capacitors.
51 VDDARX P 3.3V analog VDD input power supply with well decoupling capacitors.
52 NC No Connect
53 NC No Connect
54 AGND Gnd Analog ground
55 NC No Connect
56 NC No Connect
57 VDDA P 1.8V analog power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
58 AGND Gnd Analog ground
59 NC No connect (internal test only)
60 NC No connect (internal test only)
61 ISET O Set physical transmits output current.
Pull-down this pin with a 3.01K 1% resistor to ground.
62 AGND Gnd Analog ground
63 VDDAP P 1.8V analog power supply for PLL from VDDCO (pin 24) with appropriate filtering. If
VDDIO is 1.8V, this pin must be supplied power from the same source as pins 10, 79, 92,
108 and 125 (VDDIO) with appropriate filtering.
64 AGND Gnd Analog ground
65 X1 I
66 X2 O
25MHz crystal or oscillator clock connection.
Pins (X1, X2) connect to a crystal. If an oscillator is used, X1 connects to a 3.3V tolerant
oscillator and X2 is a no connect.
Note: Clock requirement is +/- 50ppm for either crystal or oscillator.
67 RSTN Ipu Reset Not
Hardware reset pin (active Low). This reset input is required minimum of 10ms low after
stable supply voltage 3.3V.
68 NC No Connect.
69 NC No Connect.
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Pin Number Pin Name Type Pin Function
70 NC No Connect.
71 NC No Connect.
72 NC No Connect.
73 NC No Connect.
74 NC No Connect.
75 NC No Connect.
76 A7 Ipd Address bus bit 7
77 A6 Ipd Address bus bit 6
78 DGND Gnd Digital IO ground
79 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
80 A5 Ipd Address bus bit 5
81 A4 Ipd Address bus bit 4
82 A3 Ipd Address bus bit 3
83 A2 Ipd Address bus bit 2
84 A1 Ipd Address bus bit 1
85 NC No Connect
86 NC No Connect
87 BE1N Ipd Byte Enable 1 Not, Active low for Data byte 1 enable (don’t care in 8-bit bus mode).
88 BE0N Ipd Byte Enable 0 Not, Active low for Data byte 0 enable.
89 NC No Connect
90 DGND Gnd Digital core ground
91 VDDC P 1.8V digital core power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
92 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
93 NC No Connect
94 NC No Connect
95 NC No Connect
96 NC No Connect
97 NC No Connect
98 NC No Connect
99 NC No Connect
100 NC No Connect
101 NC No Connect
102 NC No Connect
103 NC No Connect
104 NC No Connect
105 NC No Connect
106 NC No Connect
107 DGND Gnd Digital IO ground
108 VDDIO P
3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
109 NC No Connect
110 D15 I/O (pd) Data bus bit 15
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Pin Number Pin Name Type Pin Function
111 D14 I/O (pd) Data bus bit 14
112 D13 I/O (pd) Data bus bit 13
113 D12 I/O (pd) Data bus bit 12
114 D11 I/O (pd) Data bus bit 11
115 D10 I/O (pd) Data bus bit 10
116 D9 I/O (pd) Data bus bit 9
117 D8 I/O (pd) Data bus bit 8
118 D7 I/O (pd) Data bus bit 7
119 D6 I/O (pd) Data bus bit 6
120 D5 I/O (pd) Data bus bit 5
121 D4 I/O (pd) Data bus bit 4
122 D3 I/O (pd) Data bus bit 3
123 DGND Gnd Digital IO ground
124 DGND Gnd Digital core ground
125 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
126 D2 I/O (pd) Data bus bit 2
127 D1 I/O (pd) Data bus bit 1
128 D0 I/O (pd) Data bus bit 0
Legend:
P = Power supply Gnd = Ground
I/O = Bi-directional I = Input O = Output.
Ipd = Input with interna l pul l-down (58K +/-30%).
Ipu = Input with interna l pull- up ( 58K +/-30%).
Opd = Output with internal pull-down (58K +/-30%).
Opu = Output with internal pull-up (58K +/-30%).
Ipu/O = Input with internal pull-up (58K +/-30%) during power-up/reset; output pin otherwise.
Ipd/O = Input with internal pull-down (58K +/-30%) during power-up/reset; output pin otherwise.
I/O (pd) = Input/Output with internal pull-down (58K ±30%).
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Pin Configuration for 32-Bit
Figure 3. 128-Pin PQFP for 32-Bit
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Pin Description for 32-Bit
Pin Number Pin Name Type Pin Function
1 TEST_EN I Test Enable
For normal operation, pull-down this pin-to-ground.
2 SCAN_EN I Scan Test Scan Mux Enable
For normal operation, pull-down this pin-to-ground.
3 P1LED2 Opu
4 P1LED1 Ipu/O
5 P1LED0 Ipu/O
Port 1 LED indicators1 def ine d as follow s:
LED is ON when output is LOW; LED is OFF when output is HIGH.
Chip Global Control Register: CGCR
bit [15,9]
[0,0] Default [0,1]
P1LED32
P1LED2 Link/Act 100Link/Act
P1LED1 Full duplex/Col 10Link/Act
P1LED0 Speed Full duplex
Reg. CGCR bit [15,9]
[1,0] [1,1]
P1LED32 Act
P1LED2 Link
P1LED1 Full duplex/Col
P1LED0 Speed
Notes:
1. Link = On; Activity = Blink; Link/Act = On/Blink; Full Dup/Col = On/Blink;
Full Duplex = On (Full duplex); Off (Half duplex)
Speed = On (100BASE-T); Off (10BASE-T)
2. P1LED3 is pin 27.
6 NC No Connect.
7 NC No Connect.
8 NC No Connect.
9 DGND Gnd Digital ground
10 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
11 NC No Connect.
12 NC No Connect.
13 NC No Connect.
14 PME Ipu/O Power Management Event: It is asserted (low or high depends on polarity set in PMECR
register) when one of the wake-on-LAN events is detected by KSZ8851M. The
KSZ8851M is requesting the system to wake up from low power mode.
15 NC No Connect.
16 INTRN Opu Interrupt
Active Low signal to host CPU to indicate an interrupt status bit is set.
17 LDEVN Opu Local Device Not
Active Low output signal, asserted when AEN is Low and A7-A1 decode to the
KSZ8851M right address register. LDEVN is a combinational decode of the Address and
AEN signal.
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Pin Number Pin Name Type Pin Function
18 RDN Ipu Read Strobe Not
Asynchronous read strobe, active Low.
19 EECS Opd EEPROM Chip Select
This signal is used to select an external EEPROM device.
20 ARDY Opu Asynchronous Ready
ARDY may be used when interfacing asynchronous buses to extend bus access cycles. It
is asynchronous to the host CPU or bus clock. This pin need an external 4.7K pull-up
resistor.
21 NC No Connect.
22 NC No Connect
23 DGND Gnd Digital IO ground
24 VDDCO P 1.8V regulator output . This 1.8V output pin provides power to pins 38, 43, 57 (VDDA), 63
(VDDAP) and 91 (VDDC) for core VDD supply.
If VDD_IO is set for 1.8V then this pin should be left floating, pins 38, 43, 57 (VDDA), 63
(VDDAP) and 91 (VDDC) will be sourced by the external 1.8V supply that is tied to pins
10, 79, 92, 108 and 125 (VDDIO) with appropriate filtering.
25 NC No Connect.
26 EEEN Ipd EEPROM Enable
EEPROM is enabled and connected when this pin is pull-up.
EEPROM is disabled when this pin is pull-down or no connect.
27 P1LED3 Opd Port 1 LED indicator
See the description in pins 3, 4, and 5.
28 EEDO Opd EEPROM Data Out
This pin is connected to DI input of the serial EEPROM.
29 EESK Ipd/O
EEPROM Serial Clock: A 4μs (OBCR[1:0]=11 on-chip bus speed @ 25MHz) or 800ns
(OBCR[1:0]=00 on-chip bus speed @ 125MHz) serial output clock cycle to load
configuration data from the serial EEPROM.
Config Mode: The pull-up/pull-down value is latched as big or little endian mode during
power-up / reset. See “Strapping Options” section for details
30 EEDI Ipd EEPROM Data In
This pin is connected to DO output of the serial EEPROM when EEEN is pull-up.
This pin is “don’t care” (no connect) for 32-bit bus mode when EEEN is pull-down (without
EEPROM).
31 NC No Connect.
32 AEN Ipu Address Enable
Address and chip select qualifier for the address decoding and chip enable, active Low.
33 WRN Ipu Write Strobe Not
Asynchronous write strobe, active Low.
34 DGND Gnd Digital IO ground
35 NC No Connect.
36 PWRDN Ipu Full-chip power-down. Active Low (Low = Power down; High or floating = Normal
operation). All I/O pins will tri-state during chip power down.
37 AGND Gnd Analog ground
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Pin Number Pin Name Type Pin Function
38 VDDA P 1.8V analog power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
39 AGND Gnd Analog ground
40 NC No Connect
41 NC No Connect
42 AGND Gnd Analog ground
43 VDDA P 1.8V analog power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
44 NC No Connect
45 RXP1 I/O Port 1 physical receive (MDI) or transmit (MDIX) signal (+ differential)
46 RXM1 I/O Port 1 physical receive (MDI) or transmit (MDIX) signal (– differential)
47 AGND Gnd Analog ground
48 TXP1 I/O Port 1 physical transmit (MDI) or receive (MDIX) signal (+ differential)
49 TXM1 I/O Port 1 physical transmit (MDI) or receive (MDIX) signal (– differential)
50 VDDATX P 3.3V analog VDD input power supply with well decoupling capacitors.
51 VDDARX P 3.3V analog VDD input power supply with well decoupling capacitors.
52 NC No Connect
53 NC No Connect
54 AGND Gnd Analog ground
55 NC No Connect
56 NC No Connect
57 VDDA P 1.8V analog power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
58 AGND Gnd Analog ground
59 NC No connect (internal test only)
60 NC No connect (internal test only
61 ISET O Set physical transmits output current.
Pull-down this pin with a 3.01K 1% resistor to ground.
62 AGND Gnd Analog ground
63 VDDAP P 1.8V analog power supply for PLL from VDDCO (pin 24) with appropriate filtering. If
VDDIO is 1.8V, this pin must be supplied power from the same source as pins 10, 79, 92,
108 and 125 (VDDIO) with appropriate filtering.
64 AGND Gnd Analog ground
65 X1 I
66 X2 O
25MHz crystal or oscillator clock connection.
Pins (X1, X2) connect to a crystal. If an oscillator is used, X1 connects to a 3.3V tolerant
oscillator and X2 is a no connect.
Note: Clock requirement is ±50ppm for either crystal or oscillator.
67 RSTN Ipu Reset Not
Hardware reset pin (active Low). This reset input is required minimum of 10 ms low after
stable supply voltage 3.3V.
68 NC No Connect.
69 NC No Connect.
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Pin Number Pin Name Type Pin Function
70 NC No Connect.
71 NC No Connect.
72 NC No Connect.
73 NC No Connect.
74 NC No Connect.
75 NC No Connect.
76 A7 Ipd Address bus bit 7
77 A6 Ipd Address bus bit 6
78 DGND Gnd Digital IO ground
79 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
80 A5 Ipd Address bus bit 5
81 A4 Ipd Address bus bit 4
82 A3 Ipd Address bus bit 3
83 A2 Ipd Address bus bit 2
84 A1 Ipd Address bus bit 1
85 BE3N Ipd Byte Enable 3 Not, Active low for Data byte 3 enable.
86 BE2N Ipd Byte Enable 2 Not, Active low for Data byte 2 enable.
87 BE1N Ipd Byte Enable 1 Not, Active low for Data byte 1 enable.
88 BE0N Ipd Byte Enable 0 Not, Active low for Data byte 0 enable.
89 D31 I/O (pd) Data bus bit 31
90 DGND Gnd Digital core ground
91 VDDC P 1.8V digital core power supply from VDDCO (pin 24) with appropriate filtering. If VDDIO is
1.8V, this pin must be supplied power from the same source as pins 10, 79, 92, 108 and
125 (VDDIO) with appropriate filtering.
92 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
93 D30 I/O (pd) Data bus bit 30
94 D29 I/O (pd) Data bus bit 29
95 D28 I/O (pd) Data bus bit 28
96 D27 I/O (pd) Data bus bit 27
97 D26 I/O (pd) Data bus bit 26
98 D25 I/O (pd) Data bus bit 25
99 D24 I/O (pd) Data bus bit 24
100 D23 I/O (pd) Data bus bit 23
101 D22 I/O (pd) Data bus bit 22
102 D21 I/O (pd) Data bus bit 21
103 D20 I/O (pd) Data bus bit 20
104 D19 I/O (pd) Data bus bit 19
105 D18 I/O (pd) Data bus bit 18
106 D17 I/O (pd) Data bus bit 17
107 DGND Gnd Digital IO ground
108 VDDIO P
3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
109 D16 I/O (pd) Data bus bit 16
110 D15 I/O (pd) Data bus bit 15
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Pin Number Pin Name Type Pin Function
111 D14 I/O (pd) Data bus bit 14
112 D13 I/O (pd) Data bus bit 13
113 D12 I/O (pd) Data bus bit 12
114 D11 I/O (pd) Data bus bit 11
115 D10 I/O (pd) Data bus bit 10
116 D9 I/O (pd) Data bus bit 9
117 D8 I/O (pd) Data bus bit 8
118 D7 I/O (pd) Data bus bit 7
119 D6 I/O (pd) Data bus bit 6
120 D5 I/O (pd) Data bus bit 5
121 D4 I/O (pd) Data bus bit 4
122 D3 I/O (pd) Data bus bit 3
123 DGND Gnd Digital IO ground
124 DGND Gnd Digital core ground
125 VDDIO P 3.3V, 2.5V or 1.8V digital VDDIO input power supply for IO with well decoupling capacitors.
126 D2 I/O (pd) Data bus bit 2
127 D1 I/O (pd) Data bus bit 1
128 D0 I/O (pd) Data bus bit 0
Legend:
P = Power supply Gnd = Ground
I/O = Bi-directional I = Input O = Output.
Ipd = Input with interna l pul l-down (58K +/-30%).
Ipu = Input with interna l pull- up ( 58K +/-30%).
Opd = Output with internal pull-down (58K +/-30%).
Opu = Output with internal pull-up (58K +/-30%).
Ipu/O = Input with internal pull-up (58K +/-30%) during power-up/reset; output pin otherwise.
Ipd/O = Input with internal pull-down (58K +/-30%) during power-up/reset; output pin otherwise.
I/O (pd) = Input/Output with internal pull-down (58K ±30%).
Strapping Options
Pin Number Pin Name Type Pin Function
29 EESK Ipd/O Endian mode select:
Pull-up = Big Endian
Pull-down (default) = Little Endian
During power-up / reset, this pin value is latched into register CCR, bit 10.
When this pin is no connect or tied to GND, the bit 11 (Endian mode selection) in
RXFDPR register can be used to program either Little (bit11=0 default) Endian mode or
Big (bit11=1) Endian mode.
30 EEDI Ipd Bus mode select for KSZ8851M when EEEN pin is pull-down without EEPROM
Pull-up = 16-bit bus mode
Pull-down or No connect (default) = 8-bit bus mode
This pin is “don’t care” (no connect) for 32-bit bus mode when EEEN is pull-down
(without EEPROM).
During power-up / reset, this pin value is latched into register CCR bit 6/7.
Note: Ipu/O = Input with internal pull-up (58K +/-30%) during power-up/reset; output pin otherwise.
Ipd/O = Input with internal pull-down (58K +/-30%) during power-up/reset; output pin otherwise.
Pin strap-ins are latched during power-up or reset.
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Functional Description
The KSZ8851M is a single-chip Fast Ethernet MAC/PHY controller consisting of a 10/100 physical layer transceiver
(PHY), a MAC, and a Bus Interface Unit (BIU) that controls the KSZ8851M via an 8-bit, 16-bit or 32-bit host bus interface.
The KSZ8851M is fully compliant to IEEE802.3u standards.
Functional Overview
Power Management
The KSZ8851M supports enhanced power management feature in low power state with energ y detection to ensure low-
power dissipation during device idle periods. There are four operation modes under the power management function
which is controlled by two bits in PMECR (0xD4) register as shown below:
PMECR[1: 0] = 00 Norm al O per ation Mod e
PMECR[1:0] = 01 Energy Detect Mode
PMECR[1:0] = 10 Soft Power Down Mode
PMECR[1 :0] = 11 Po wer S aving Mo de
Table 1 indicates all internal function blocks status under four different power management operation modes.
Power Management Operation Modes
KSZ8851M
Function Blocks Normal mode Power saving mode Energy detect mode Soft power down mode
Internal PLL Clock Enabled Enabled Disabled Disabled
Tx/Rx PHY Enabled Rx unused block disabled Energy detect at Rx Disabled
MAC Enabled Enabled Disabled Disabled
Host Interface Enabled Enabled Disabled Disabled
Table 1. Internal Function Blocks Status
Normal Operation Mode
This is the default setting bit[1:0]=00 in PMECR register after the chip power-up or hardware reset (pin 67). When
KSZ8851M is in this normal operation mode, all PLL clocks are running, PHY and MAC are on and the host interface is
ready for CPU read or write.
During the normal operation mode, the host CPU can set the bit[1:0] in PMECR register to transit the current normal
operation mode to any one of the other three power management operation modes.
Energy Detect Mode
The energy detect mode provides a mechanism to save more power than in the normal operation mode when the
KSZ8851 M is not connecte d to an ac tive link partner . For ex ample, if cable is not present or it is connecte d to a p owered
down partner, the KSZ8851M can automatically enter to the low power state in energy detect mode. Once activity
resumes due to pl ugg ing a c able or attempting by the far en d to es ta bl is h link, the KSZ 8 851 M can automatic a lly power up
to normal power state in energy detect mode.
Energy detect mode consists of two states, normal power state and low power state. While in low power state, the
KSZ8851M reduces power consumption by disabling all circuitry except the energy detect circuitry of the receiver. The
energy detect mode is entered by setting bit[1:0]=01 in PMECR register. When the KSZ8851M is in this mode, it will
monitor the cable energy. If there is no energy on the cable for a time longer than pre-configured value at bit[7:0] Go-
Sleep tim e in GSW UTR register , KSZ8851M wil l go into a low power state. W hen KSZ8851 M is in low power s tate, it will
keep monitoring the cable energy. Once the energy is detected from the cable and is continuously presented for a time
longer than pre-configured value at bit[15:8] Wake-Up time in GSWUTR register, the KSZ8851M will enter either the
normal power state if the auto-wakeup enable bit[7] is set in PM ECR register or the norm al operation mode if both auto-
wakeup enable bit[7] and wakeup to normal operation mode bit[6] are set in PMECR register.
The KSZ8851M will also assert PME output pin if the corresponding enable bit[8] is set in PMECR (0xD4) register or
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generate in ter rupt to s ig na l an energy detect event occ urr ed if the c orr es pondin g e nab le bit [2] is s et in IER (0x90) regis ter .
Once the po wer management un it detects the PME o utput asserted or interrupt ac tive, it will power up th e host CPU and
issue a wakeup command which is a read cycle to read the Globe Reset Register (GRR at 0x26) to wake up the
KSZ8851M from the low power state to the normal power state in case the auto-wakeup enable bit[7] is disabled. When
KSZ8851M is at normal power state, it is able to transmit or receive packet from the cable.
Soft Power Do w n Mod e
The s oft power d own m ode is enter ed b y setting bit [1: 0]=10 in P MECR r egister . When KSZ8851M is in this m ode, all PLL
clocks are disabled, the PHY and the MAC are off, all internal registers value will not change, and the host interface is
only used to wake-up this device from current soft power down mode to normal operation mode.
In order to go back the normal operation mode from this soft power down mode, the only way to leave this mode is
through a host wake-up command which the CPU issues to read the Globe Reset Register (GRR at 0x26).
Power Saving Mode
The power saving mode is entered when auto-negotiation mode is enabled, cable is disconnected, and by setting
bit[1:0]=11 in PMECR register and bit [10 ]=1 in P1SC LMD register. W hen KSZ8851M is in this mode, all PLL clocks are
enabled, M AC is on, all internal r egisters value will not change, and host interface is read y for CPU r ead or write. I n this
mode, it mainly controls the PHY transceiver on or off based on line status to achieve power saving. The PHY remains
transm itting and on ly turns off the unused r eceiver b lock. Once activi ty resum es due to plugg ing a cab le or attempting by
the far end to establish link, the KSZ8851M can automatically enabled the PHY power up to normal power state from
power saving mode.
During this p ower savin g mode, the hos t CPU can pr ogram the bit[1:0] in PMECR r egister and s et bit[10]=0 in P1SCLMD
register to transit the current power saving mode to any one of the other three power management operation modes.
Power Down
There is a full chip power-down mode if PWRDN (pin 36) is tied to low. When this pin is pulled-down, the entire chip
powers down. Transitioning this pin from pull-down to pull-up results in a power up and chip reset. The reset will set all
registers to default values. The host CPU will need to re-program all register values again after release of the PWRDN.
Wake-on-LAN
Wake-up frame events are used to wake the system whenever meaningful data is presented to the system over the
network. Examples of meaningful data include the reception of a Magic Packet, a management request from a remote
adminis trator, or sim ply network tr affic dir ectly target ed to the loc al s ystem. In all o f thes e instanc es, the networ k device is
pre-programmed by the policy owner or other software with information on how to identify wake frames from other network
traff ic. The KSZ 8851M co ntroller can be pr ogramm ed to notif y the host of the wake- up fram e detection with the ass ertion
of the interrupt signal (INTRN) or assertion of the power management event signal (PME).
A wake-up event is a request for hardware and/or software external to the network device to put the system into a
powered state (working).
A wake-up signal is caused by:
1. Detection of energy signal over a pre-configured value (bit 2 in ISR register)
2. Detection of a linkup in the network link state (bit 3 in ISR register)
3. Receipt of a Magic Packet (bit 4 in ISR register)
4. Receipt of a network wake-up frame (bit 5 in ISR register)
There ar e als o oth er types of wak e- up e vents tha t ar e not lis te d her e as manuf ac ture rs m a y choose to implement thes e in
their own wa y.
Detection of Energy
The energy is detected from the cable and is continuously presented for a time longer than pre-configured value,
especially when this energy change may impact the level at which the system should re-enter to the normal power state.
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Detection of Linkup
Link status wake events are useful to indicate a linkup in the network’s connectivity status.
Wake-up Packet
Wake-up packets are certain types of packets with specific CRC values that a system recognizes as a ‘wake up’ frame.
The KSZ8851M supports up to four users defined wake-up frames as below:
1. Wake-up frame 0 is defined in wakeup fram e registers (0x30 – 0x3B) a nd is enabled by bit 0 in wak eup frame control
register (0x2A).
2. Wake-up frame 1 is defined in wakeup fram e registers (0x40 – 0x4B) a nd is enabled by bit 1 in wak eup frame control
register (0x2A).
3. Wake-up frame 2 is defined in wakeup fram e registers (0x50 – 0x5B) a nd is enabled by bit 2 in wak eup frame control
register (0x2A).
4. Wake-up frame 3 is defined in wakeup fram e registers (0x60 – 0x6B) a nd is enabled by bit 3 in wak eup frame control
register (0x2A).
Magic Packet
Magic Packet technology is used to remotely wake up a sleeping or powered off PC on a LAN. This is accom plished by
sending a specific pack et of inform ation, called a Magic Packet frame, to a node on the network . When a PC capable of
receivin g the specif ic fram e goes to sleep, it e na bles th e Ma gic Pac ket RX mode i n th e L AN c o ntro ller , an d when the LAN
controller receives a Magic Packet frame, it will alert the system to wake up.
Magic Packet is a standard feature integrated into the KSZ8851M. The controller implements multiple advanced power-
down modes including Magic Packet to conserve power and operate more efficiently.
Once the KSZ 8851M has been put i nto Magic Pack et Enabl e mode (W F CR[7]=1), it sc ans all incom ing f rames address ed
to the node for a specific data sequence, which indicates to the controller this is a Magic Packet (MP) frame.
A Magic Packet frame must also meet the basic requirements for the LAN technology chosen, such as Source Address
(SA), Destination Address (DA), which may be the receiving station’s IEEE address or a multicast or broadcast address
and CRC.
The specific sequence consists of 16 duplications of the IEEE addr ess of this node, with no breaks or interruptions. T his
sequence can be located anywhere within the packet, but must be preceded by a synchronization stream. The
synchron ization stream allows th e scanning s tate machin e to be muc h simpler. T he synchroniza tion stream is define d as
6 bytes of FFh. The device will a lso accept a broa dcast fram e, as long as the 16 duplicati ons of the IEEE a ddress match
the address of the machine to be awakened.
Example:
If the IEEE address for a particular node on a network is 11h 22h, 33h, 44h, 55h, 66h, the LAN controller would be
scanning for the data sequence (assuming an Ethernet frame):
DESTINAT ION SOURCE – MI SC - FF FF FF FF FF FF - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 -
11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 -
11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 - 11 22 33 44 55 66 -
11 22 33 44 55 66 - MISC - CRC.
There ar e no fur ther restric tions on a Magic Pack et fram e. For instance, the sequ ence could be in a TCP/IP pack et or an
IPX pack et. The fr am e may be br idged or route d across the network without af fecting its abilit y to wak e-up a node at the
frame’s destination.
If the LAN contr oll er sc ans a fr ame and does not find t he specif ic s equence s how n above, it disc ards the f ram e and tak es
no further action. If the KSZ8851M controller detects the data sequence, however, it then alerts the PC’s power
management circuitry (assert the PME pin) to wake up the system.
Physical Layer Transceiver (PHY)
100BASE-TX Transmit
The 100BASE-TX transmit function performs parallel-to-serial conversion, 4B/5B coding, scrambling, NRZ-to-NRZI
conversion, and MLT3 encoding and transmission.
The c ircuitry starts with a p arallel-t o-seria l conversi on, which c onverts the MII dat a from the MAC into a 1 25MHz seria l bit
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stream . The data and contr ol stream is then converted into 4 B/5B coding, f ollowed by a scr ambler. The ser ialized data is
further converted from NRZ-to-NRZI format, and then transmitted in MLT3 current output. An external 3.01kΩ (1%)
resistor for the 1:1 transformer ratio sets the output current.
The output signal has a typical rise/fall time of 4ns and complies with the ANSI TP-PMD standard regarding amplitude
balance, o vers ho ot, a nd t i ming jitter . T he wa ve-s ha p ed 10 BA S E-T output dri v er is als o i ncor por a ted into the 100 BA SE- T X
driver.
100BASE-TX Receive
The 100BASE-TX receiver function performs adaptive equalization, DC restoration, MLT3-to-NRZI conversion, data and
clock recovery, NRZI-to-NRZ conversion, de-scrambling, 4B/5B decoding, and serial-to-parallel conversion.
The rec eiving side starts with the equalizat ion filter to c ompens ate for inter-s ymbol int erference ( ISI) over the twisted p air
cable. Since the amplitude loss and phase distortion is a function of the cable length, the equalizer has to adjust its
characteristics to optimize performance. In this design, the variable equalizer makes an initial estimation based on
compar isons of i ncom ing signal s trength against som e known cab le charac teristic s, and th en tunes itself for optim ization.
This is an ongoing process and self-adjusts against environmental changes such as temperature variations.
Next, the equal ized s ignal goes t hroug h a DC restor ation and data con versi on bl ock . The DC res torati on c ircuit is use d to
compensate for the effect of baseline wander and to improve the dynamic range. The differential data conversion circuit
converts the MLT3 format back to NRZI. The slicing threshold is also adaptive.
The c lock recovery circuit e x trac ts the 125MH z cloc k from the edges of the NRZI sign al. This r ec overed c lock is then use d
to convert the NRZI signal into the NRZ format. This signal is sent through the de-scrambler followed by the 4B/5B
decoder. Finally, the NRZ serial data is converted to an MII format and provided as the input data to the MAC.
PLL Clock Synthesizer (Recovery)
The interna l PLL c lock synthesi zer can gen erate eith er 125MH z, 62.5MH z, 41.66 MH z, or 25MHz c lock s b y setting the on-
chip bus control register (0x20) for KSZ8851M system timing. These internal clocks are generated from an external
25MHz crystal or oscillator.
Scrambler/De-scrambler (100BASE-TX only)
The purpos e of the scram bler is to s pread th e power s pectrum of the s ignal to r educe e lectromagnet ic inter ference ( EMI)
and baselin e wander .
Transmitted data is scrambled through the use of an 11-bit wide linear feedback shift register (LFSR). The scrambler
generates a 2047-bit non- repetitive se quence. T hen the receiver d e-scrambles the incoming data s tream using th e same
sequence as at the transmitter.
10BASE-T Transmit
The 10BASE-T driver is incorporated with the 100BASE-TX driver to allow for transmission using the same magnetics.
The y are inter na ll y wav e-s haped and pr e-emphas i zed into ou tputs with typical 2.4 V amplitu de. T he har monic c ontents are
at least 27 dB below the fundamental frequency when driven by an all-ones Manchester-encoded signal.
10BASE-T Receive
On the receive side, input buffers and level detecting squelch circuits are employed. A differential input receiver circuit and
a phase-locked loop (PLL) perform the decoding function.
The Manchester-encoded data stream is separated into clock signal and N RZ data. A squelch circuit rejects signals with
levels less than 40 0mV or with sh ort pulse widths to preven t noise at the RX P1 or RXM1 in put from fals ely tr iggering the
decoder. When the input e x c eeds the sq ue lc h l imit, the P LL loc ks onto the i nc om ing s ign al and th e K SZ8 851M dec odes a
data frame. The receiver clock is maintained active during idle periods in between data reception.
MDI/MDI-X Auto Crossover
To eliminate the need for crossover cables between similar devices, the KSZ8851M supports HP-Auto MDI/MDI-X and
IEEE 802.3u standard MDI/MDI-X auto crossover. HP-Auto MDI/MDI-X is the default.
The auto-s ens e f unc tio n de tect s r em ote trans mit and rec ei ve pair s and cor rec tly ass igns the tr ansmit and r ec ei ve pa irs f or
the KSZ8851M device. This feature is extrem ely useful when end users are unaware of cable t ypes in addition to saving
on an additional uplink configuration connection. The auto-crossover feature can be disabled through the port control
registers. The IEEE 802.3u standard MDI and MDI-X definitions are as below:
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MDI MDI-X
RJ45 Pins Signals RJ45 Pins Signals
1 TD+ 1 RD+
2 TD- 2 RD-
3 RD+ 3 TD+
6 RD- 6 TD-
Table 2. MDI/MDI-X Pin Definitions
Straight Cable
A straig ht cable c onnec ts an MDI dev ice to a n MDI-X dev ice or an MDI-X dev ice to an MDI de vice. T he foll owing dia gram
shows a typical straight cable connection between a network interface card (NIC) and a switch, or hub (MDI-X).
Figure 4. Typical Straight Cable Connection
Crossover Cab le
A crossover cable connects an MDI device to another MDI device, or an MDI-X device to another MDI-X device. The
following diagram shows a typical crossover cable connection between two chips or hubs (two MDI-X devices).
Receive PairTransmit Pair
Receive Pair
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
Transmit Pair
Modular Connector
(RJ-45)
NIC
Straight
Cable
10/100 Ethernet
Media Dependent Interface 10/100 Ethernet
Media Dependent Interface
Modular Connector
(RJ-45)
HUB
(Repeater or Switch)
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Receive Pair Receive Pair
Transmit Pair
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
Transmit Pair
10/100 Ethernet
Media Dependent Interface 10/100 Ethernet
Media Dependent Interface
Modular Connector (RJ-45)
HUB
(Repeater or Switch)
Modular Connector (RJ-45)
HUB
(Repeater or Switch)
Crossover
Cable
Figure 5. Typical Crossover Cable Connection
Auto Negotiation
The KSZ8851M conforms to the auto negotiation protocol as described by the 802.3 committee to allow the port to
operate at either 10Base-T or 100Base-TX.
Auto negot iation a llows u nshielded twis ted pair ( UTP) li nk partners to sele ct the bes t comm on mode of oper ation. In a uto
negotiat ion, th e link partners advert ise capab ilit ies acr oss the link to eac h other . If auto negot iatio n is not su pporte d or the
link par tner to the KSZ 8 851 M is f or ced to b ypas s aut o nego tia tio n, the m ode is s et b y obs erv in g th e s ig na l at t he rec ei ver.
This is known as para llel mode because while the transmitter is send ing auto negotiation advertisem ents, the receiver is
listening for advertisements or a fixed signal protocol.
The link setup is shown in the following flow diagram (Figure 6).
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Force Link Setting
Listen for 10BASE-T L i n k
Pulse s
Listen for 100BASE-TX
Idles
A
ttempt Auto
Negotiation
Link Mode Set
B y p a s s
A
u t o N e g o t i a t i o n
and Set Link Mode
Link Mode Set ?
Parallel
Operation
Join Flow
NO
NO
YES
YES
Start Auto Negotiation
Figure 6. Auto Negotiation and Parallel Operation
LinkMD® Cable Diagnostics
The KSZ8851M LinkMD® uses time domain reflectometry (TDR) to analyze the cabling plant for common cabling
problems such as open circuits, short circuits, and impedance mismatches.
LinkMD® works by sending a pulse of known amplitude and duration down the MDI and MDI-X pairs and then analyzes
the shape of the reflected signal. Timing the pulse duration gives an indication of the distance to the cabling fault with a
maximum distance of 200m and an accurac y of +/–2m. Internal circuitry displays the TDR information in a user-readable
digital format in register P1SCLMD[8:0].
Note: cable diagnostics are only valid for copper connections – fiber-optic operation is not supported.
Access
LinkMD® is initiated by accessing register P1SCLMD, the PHY special control/status and LinkMD® register (0xF4).
Usage
LinkMD® can be run at any time by ensuring that Auto-MDIX has been disabled. To disable Auto-MDIX, write a ‘1’ to
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P1CR[10] to enable manual control over the pair used to transmit the LinkMD® pulse. The self-clearing cable diagnostic
test enable bit, P1SCLMD [12], is set to ‘1’ to start the test on this pair.
When bit P1SCLMD[12] returns to ‘0’, the test is complete. The test result is returned in bits P1SCLMD[14:13] and the
distance is returned in bits P1SCLMD[8:0]. The cable diagnostic test results are as follows:
00 = Valid test, normal condition
01 = Valid test, open circuit in cable
10 = Valid test, short circuit in cable
11 = Invalid test, LinkMD® failed
If P1SCLMD[14:13]=11, this indicates an invalid test, and occurs when the KSZ8851M is unable to shut down the link
partner. In t his ins tance, th e test is not r un, as it is not possible f or the KSZ88 51M to determine if the detec ted signa l is a
reflection of the signal generated or a signal from another source.
Cable distance can be approximated by the following formula:
P1SCLMD[8:0] x 0.4m for port 1 cable distance
This constant m ay be calibrated f or diff erent cabling c onditi ons, inclu ding cab les with a v elocity of propagati on that varies
significantly from the norm.
Media Access Control (MAC) Operation
The KSZ8851M strictly abides by IEEE 802.3 standards to maximize compatibility.
Inter Packet Gap (IPG)
If a frame is successfully transmitted, then the minimum 96-bit time for IPG is measured between two consecutive
packets. If the current pack et is experiencing collisions, the m inimum 96-bit t ime for IPG is m easured from carrier sense
(CRS) to the next transmit packet.
Back-Off Algorithm
The KSZ8 851M im plements the I EEE stand ard 802.3 binary expon ential bac k-off algorit hm in half -duplex mode. After 16
collis ions, the pac ket is dropped .
Late Collision
If a transmit packet experiences collisions after 512 bit times of the transmission, the packet is dropped.
Flow Control
The KSZ8851M supports standard 802.3x flow control frames on both transmit and receive sides.
On the receive side, if the KSZ8851M receives a pause control frame, the KSZ8851M will not transmit the next normal
frame until the tim er, specified in the pause control f rame, expires. If anot her pause frame is received before the current
timer expires, the timer will be updated with the new valu e in the second pause frame. During this period (while it is flow
controlled), only flow control packets from the KSZ8851M are transmitted.
On the tr ansm it side, the KSZ8851M has in telligent a nd eff icient wa ys to determ ine wh en to in voke flo w contr ol. The f low
control is based on availability of the system resources.
There are three programmable low watermark register FCLWR (0xB0), high watermark register FCHWR (0xB2) and
overrun watermark register FCOW R (0xB4) for flow control in RXQ FIFO. The KSZ8851M will send PAUSE frame when
the RXQ buffer hit the h igh waterm ark level (default 3 .072 KByte av ailable) and stop PAUSE f ram e when the RX Q buf fer
hit the low watermark level (default 5.12 KByte available). The KSZ8851M will drop packet when the RXQ buffer hit the
overrun watermark level (default 256-Byte available).
The KSZ8851M issues a flow control frame (Xoff, or transm itter off), containing the m aximum pause time defined in IEEE
standard 802.3x. Once the resource is freed up, the KSZ8851M sends out the another flow control frame (Xon, or
transmitter on) with zero pause tim e to turn off the flow control (turn on transmission to the port). A hysteresis feature is
provided to prevent the flow control mechanism from being constantly activated and deactivated.
Half-Duplex Backpressure
A half-duplex backpressure option (non-IEEE 802.3 standards) is also provided. The activation and deactivation
conditio ns are the sam e as in f ull-dupl ex mode. If backpr essure is r equired, the KSZ 8851M s ends pream bles to def er the
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other stations' transmission (carrier sense deference).
To avoid jabber and excessive deference (as defined in the 802.3 standard), after a certain time, the KSZ8851M
discontinues the carrier sense and then raises it again quickly. This short silent time (no carrier sense) prevents other
stations from sending out pack ets thus keepin g other statio ns in a carr ier sense def erred state. If the port has packets to
send during a backpressure situation, the carrier sense type backpressure is interrupted and those packets are
transmitted instead. If there are no additional packets to send, carrier sense type backpressure is reactivated again until
chip resources free up. If a collision occurs, the binary exponential back-off algorithm is skipped and carrier sense is
generated immediately, thus reducing the chance of further collision and carrier sense is maintained to prevent packet
reception.
Address Filtering Function
The KSZ8851M supports 11 different address filtering schemes as shown in the following Table 3. The Ethernet
destination address (DA) field inside the packet is the first 6-byte field which uses to compare with either the host MAC
address registers (0x10 – 0x15) or the MAC address hash table registers (0xA0 – 0xA7) for address filtering operation.
The f irst bit ( bit 40) of the des tinatio n addr ess ( DA) in the E thernet p ack et dec ides whether th is is a ph ysica l addr ess if bit
40 is “0” or a multicast address if bit 40 is “1”.
Receive Control Register (0x74 – 0x75): RXCR1
Item Address
Filtering Mode RX All
(Bit 4)
RX
Inverse
(Bit 1)
RX Physical
Address
(Bit 11)
RX Multicast
Address
(Bit 8)
Description
1 Perfect 0 0 1 1 All Rx frames are passed only if the DA exactly
matches the MAC address in MARL, MARM
and MARH registers.
2 Inverse perfect 0 1 1 1 All Rx frames are passed if the DA is not
matching the MAC address in MARL, MARM
and MARH registers.
3 Hash only 0 0 0 0 All Rx frames with either multicast or physical
destination address are filtering against the
MAC address hash table.
4 Inverse hash
only 0 1 0 0
All Rx frames with either multicast or physical
destination address are filtering not against the
MAC address hash table.
All Rx frames which are filtering out at item 3
(Hash only) only are passed in this mode.
5 Hash perfect
(Default) 0 0 1 0
All Rx frames are passed with Physical
address (DA) matching the MAC address and
to enable receive multicast frames that pass
the hash table when Multicast address is
matching the MAC address hash table.
6 Inverse hash
perfect 0 1 1 0
All Rx frames which are filtering out at item 5
(Hash perfect) only are passed in this mode.
7 Promiscuous 1 1 0 0
All Rx frames are passed without any
conditions.
8
Hash only with
Multicast
address
passed
1 0 0 0
All Rx frames are passed with Physical
address (DA) matching the MAC address hash
table and with Multicast address without any
conditions.
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9
Perfect with
Multicast
address
passed
1 0 1 1
All Rx frames are passed with Physical
address (DA) matching the MAC address and
with Multicas t address without an y conditions.
10
Hash only with
Physical
address
passed
1 0 1 0
All Rx frames are passed with Multicast
address matching the MAC address hash
table and with Physical address without any
conditions.
11
Perfect with
Physical
address
passed
1 0 0 1
All Rx frames are passed with Multicast
address matching the MAC address and with
Physical address without any conditions.
Notes:
1. Bit 0 (RX Enable), Bit 5 (RX Unicast Enable) and Bit 6 (RX Multicast Enable) must set to 1 in RXCR1 register.
2. The KSZ8851M will discard frame with SA same as the MAC address if bit[0] is set in RXCR2 register.
Table 3. Address Filtering Scheme
Clock Generator
The X 1 and X2 pins are connec ted to a 25 MHz c rystal. X1 c an also serve as the connector to a 3.3V, 25 MH z osc illator
(as descr ibed in the pin d esc r iptio n).
Bus Interface Unit (BIU)
The BIU host interface is a generic bus interface, designed to communicate with embedded processors. No glue logic is
required when it talks to various standard asynchronous buses and processors.
Supported Transfers
In terms of transfer type, the BIU can support asynchronous transfer or SRAM-like slave mode. To support the data
transfers, the BIU provides a group of signals:
Asynchronous or SRAM-like signals: Address/Data (A[7:1]/D[15:0]), Address Enable (AEN), Read (RDN), Write (WRN),
Byte Enable (BE[3:0]N), Async Ready (ARDY) and Interrupt (INTRN).
Physical Data Bus Size
The BIU supports an 8-bit, 16-bit or 32-bit host standard data bus. Depending on the size of the physical data bus, the
KSZ8851M can support 8-bit, 16-bit or 32-bit data transfers.
For example,
For a 32-bit system/host data bus, the KSZ8851-32MQL allows an 8-bit, 16-bit and 32-bit data transfer.
For a 16-bit system/host data bus, the KSZ8851-16MQL allows an 8-bit and 16-bit data transfer.
For an 8-bit system/host data bus, the KSZ8851-16MQL only allows an 8-bit data transfer.
The KSZ 8851M s upports i nternal dat a byte- swap and word-swap . This m eans that th e s ystem /host dat a bus HD[7:0] just
connect to D[7:0] for an 8-bit data bus interface. For a 16-bit data bus, the system/host data bus HD[15:8] and HD[7:0]
only need to connect to D[15:8] and D[7:0] respectively.
Table 4 describes the BIU signal grouping.
Signal Type Function
A[7:1] Input
Address Bus
D[15:0] I/O Data Bus, For both KSZ8851-32MQL and KSZ8851-16MQL devices.
D[31:16] I/O Data Bus , For KSZ8851-32MQL device only.
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Signal Type Function
AEN Input
Address Enable
Address Enable asserted indicates memory address on the bus for DMA access and since the
device is an I/O device, address decoding is only enabled when AEN is Low.
BE3N, BE2N,
BE1N, BE0N Input Byte Enable
BE0N BE1N BE2N BE3N Description
0 0 0 0 32-bit access
0 0 1 1 Lower 16-bit (D[15:0]) access
1 1 0 0 Higher 16-bit (D[31:16]) access
0 1 1 1 Byte 0 (D[7:0]) access
1 0 1 1 Byte 1 (D[15:8]) access
1 1 0 1 Byte 2 (D[23:16]) access
1 1 1 0 Byte 3 (D[31:24]) access
INTRN Output
Interrupt
RDN Input
Asynchronous Read
WRN Input
Asynchronous Write
ARDY Output
Asynchronous Ready, This signal is asserted (Low) to ask CPU inserting wait state.
Table 4. Bus Interface Unit Signal Grouping
Note: The LDEVN output signal will be asserted to indicate that the KSZ8851M is successfully targeted. The signal
LDEVN is a combinatorial decode of AEN and A[7:1].
Little and Big Endian Support
The KSZ8851M supports either Little- or Big-Endian microprocessor. The external strap pin 29 (EESK) is used to select
between t wo modes . The KSZ 88 51M op erates in L ittl e En di an whe n th is p in is pu l led-d o wn or in B ig En dia n when th is p in
is pulled-up.
When this pin 29 is no connect or tied to GND, the bit 11 (Endian mode selection) in RXFDPR register can be used to
program either Little (bit11=0) Endian mode or Big (bit11=1) Endian mode.
Asynchronous Inter face
For asynchronous transfers, the asynchronous interface uses RDN (read) and WRN (write) signal strobes for data
latching. If necessary, ARDY is de-asserted on the falling edge of the strobe.
All asynchronous transfers are either single-data or burst-data transfers. Byte, word, and double word data buses and
accesses (transfers) are supported. The BIU, however, provides flexible asynchronous interfacing to communicate with
various a pplicat ions and architectur es. No a dditional a ddress latc h is r equired. T he BIU dec odes A [7:1] and qualifies with
AEN (Address Enable) to determine if the KSZ8851M device is the intended target. The host utilizes the rising edge of
RDN to latch read data and the KSZ8851M will use falling edge of WRN to latch write data.
BIU Summation
Figure 7 shows the connection for different data bus sizes. Also refer to reference schematics in hardware design
package.
Note: For the 8-bit d ata bus m ode, the inter nal invert er is enab led and co nnected bet ween BE0N a nd BE1N, so a n even
address will enable the BE0N and an odd address will enable the BE1N.
Strapping Options:
EESK (pin 29, Ipd/O): Pull-down or no connect (default) selects Little Endian. Pull-up selects Big Endian.
EEDI (pin 30, Ipd): Pull-down or no connect (default) selects 8-bit bus mode. Pull-up selects 16-bit bus mode.
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Figure 7. KSZ8851M 8-Bit, 16-Bit, and 32-Bit Data Bus Connections
Queue Management Unit (QMU)
The Queue Man agem ent Unit (Q MU) m anages pack et traff ic between the MA C/PH Y interfac e and the s ystem hos t. It has
built-in pac ket m emory for rec eive and trans mit f unctions c alled TX Q (Transm it Queue) and RX Q (Recei ve Queue). Each
queue cont ains 12KB f or RXQ and 6 KB for TX Q of memor y with bac k-to-back , non-block ing frame tr ansfer perform ance.
It provides a gr o up of c ontr ol r e gis ters f or system c ont rol, f r ame s tatus r egis t ers f or c urr ent packet tr ansmit/rec ei ve s ta tus ,
and interrupts to inform the host of the real time TX/RX status.
Transmit Queue (TXQ) Frame Format
The fram e format for the tr ansmit queue is sho wn in the follo wing Table 5. T he first word cont ains the contr ol inform ation
for the frame to transmit. The second word is used to specify the total number of bytes of the frame. The packet data
follows. The packet data area holds the frame itself. It may or may not include the CRC checksum depending upon
whether hardware CRC checksum generation is enabled in TXCR (bit 1) register.
Multiple frames can be pipelined in both the transmit queue and receive queue as long as there is enough queue memory,
thus avoiding overrun. For each transmitted frame, the transmit status information for the frame is located in the TXSR
(0x72) register.
Packet Memory
Address Offset Bit 15 Bit 0
2nd Byte 1st Byte
0 Control Word (High byte and low byte need
to swap in Big-Endian mode)
2 Byte Count (High byte and low byte need to
swap in Big-Endian mode)
4 - up Transmit Packet Data
(maximum size is 2000)
Table 5. Frame Format for Transmit Queue
Since multiple packets can be pipelined into the TX packet m emory for transmit, the transm it status reflects the status of
the packet that is currently being transferred on the MAC interface, which may or may not be the last queued packet in the
TX queue.
The transmit control word is the first 16-bit word in the TX packet memory, followed by a 16-bit byte count. It must be word
aligned. Each control word corresponds to one TX packet. Table 6 gives the transmit control word bit fields.
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Bit Description
15 TXIC Transmit Interrupt on Completion
When this bit is set, the KSZ8851M sets the transmit interrupt after the present frame has been
transmitted.
14-6 Reserved.
5-0 TXFID Transmit Frame ID
This field specifies the frame ID that is used to identify the frame and its associated status information
in the transmit status register.
Table 6. Transmit Control Word Bit Fields
The transmit Byte Count specifies the total number of bytes to be transmitted from the TXQ. Its format is given in Table 7.
Bit Description
15-11 Reserved.
10-0 TXBC Transmit Byte Count
Transmit Byte Count. Hardware uses the byte count information to conserve the TX buffer memory for
better utilizatio n of the packet mem ory .
Note: The hardware behavior is unknown if an incorrect byte count information is written to this field.
Writing a 0 value to this field is not permitted.
Table 7. Transmit Byte Count Format
The data ar ea contains s ix b ytes of Des ti nat io n Addr ess ( DA) f oll o wed by six bytes of Sour c e Ad dr ess ( S A), f oll o we d by a
variable-length number of bytes. On transmit, all bytes are provided by the CPU, including the source address. The
KSZ8851 M does not insert its o wn SA. The 802. 3 Fram e Length word (Fram e Type in Ether net) is not interpr eted by the
KSZ8851M. It is treated transparently as data both for transmit operations.
Frame Transmitting Path Operation in TXQ
This sec tion des c ribes the t ypical r eg ist er s ett ings f or t rans mitting p ac k ets f r om host pr oces s or to KSZ8 85 1 M with ge ner ic
bus interface. User can use the default value for most of the transmit registers. The following Table 8 describes all
registers which need to be set and used for transmitting single or multiple frames.
Register Name
[bit](offset) Description
TXCR[3:0](0x70)
TXCR[8:5](0x70)
Set transmit control function as below:
Set bit 3 to enable transmitting flow control. Set bit 2 to enable transmitting padding.
Set bit 1 to enable transmitting CRC. Set bit 0 to enable transmitting block operation.
Set transmit checksum generation for ICMP, UDP, TCP and IP packet.
TXMIR[12:0](0x78) The amount of free transmit memory available is represented in units of byte. The TXQ memory (6 KByte) is
used for both frame payload and control word.
TXQCR[0](0x80) For single frame to transmit, set this bit 0 = 1(manual enqueue). the KSZ8851M will enable current TX frame
prepared in the TX buffer is queued for transmit, this is only transmit one frame at a time.
Note: This bit is self-clearing after the frame is finished transmitting. The software should wait for the bit to
be cleared before setting up another new TX frame.
TXQCR[1](0x80) W hen this bit is written as 1, the KSZ8851M will generate interrupt (bit 6 in ISR register) to CPU when TXQ
memory is available based upon the total amount of TXQ space requested by CPU at TXNTFSR (0x9E)
register.
Note: This bit is self-clearing after the frame is finished transmitting. The software should wait for the bit to
be cleared before set to 1 again
TXQCR[2](0x80) For multiple frames to transmit, set this bit 2 = 1 (auto-enqueue). the KSZ8851M will enable current all TX
frames prepared in the TX buffer are queued to transmit automatically.
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Register Name
[bit](offset) Description
RXQCR[3](0x82) Set bit 3 to start DMA access from host CPU either read (receive frame data) or write (transmit data frame)
TXFDPR[14](0x84) Set bit 14 to enable TXQ transmit frame data pointer register increments automatically on accesses to the
data register.
IER[14][6](0x90) Set bit 14 to enable transmit interrupt in Interrupt Enable Register
Set bit 6 to enable transmit space available interrupt in Interrupt Enable Register.
ISR[15:0](0x92) Write 1 (0xFFFF) to clear all interrupt status bits after interrupt occurred in Interrupt Status Register.
TXNTFSR[15:0](0x9E) The host CPU is used to program the total amount of TXQ buffer space which is required for next total
transmit frames siz e in doubl e- word count.
Table 8. Registers Setting for Transmit Function Block
Driver Routine for Transmit Packet from Host Processor to KSZ8851M
The transmit r outin e is c al le d b y the u pper layer to tra n smit a contig uous b lock of data thr oug h th e Et her ne t contr ol ler. It is
user’s choice to decide how the transmit routine is implemented. If the Ethernet controller encounters an error while
transm itting the frame, it’s the user’s choice to decide whether the driver should attempt to retransmit the same frame or
discard the data. T he following F igures 8 and 9 show s the step-b y-st ep for s ingle and m ultiple tr ansmit pac kets fr om host
processor to KSZ8851M.
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Figure 8. Host TX Single Frame in Manual Enqueue Flow Diagram
Host receives an Ethernet pkt from
upper layer and prepares transmit pkt
data (data, data_length, frame ID).
The transmit queue frame format is
shown in Table 5
Check if KSZ8851M TXQ
Memory size is available for this
transmit pkt ?
(Read TXMIR Reg)
Write an 1? to RXQCR[3] reg to enable
TXQ write access, then Host starts
write transmit data (con tro l word, byt e
count and pkt data) to TXQ memory.
This is moving transmit data from Host
to KSZ8851M TXQ memory until whole
pkt is finished
Write an 0?to RXQCR[3] reg to end
TXQ write access
Write an 1?to TXQCR[0] reg to issue a
transmit command (manual-enqueue)
to the TXQ. The TXQ wi ll tran s mit th is
pkt data to the PHY port
Option to Read ISR[14] reg, it indicates
that the TXQ has completed to transmit
at least one pkt to the PHY port, then
Write 1? to clear this bit
Yes
No
Write the total amount of TXQ buffer
space which is required for next
transmit frame size in double-word
count in TXNTFSR[15:0] register
Set bit 1=1 in TXQCR register to
enable the TXQ memory available
monitor
Wait for interrupt
and check if the bit 6=1
(memory space available)
in ISR register
?
Yes No
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Figure 9. Host TX Multiple Frames in Auto- Enqueue Flow Diagram
Host receives an multiple Ethernet pkt s
from upper layer and prepares transmit
pkts data (data, data_length, frame
ID). Each transmit queue frame format
is shown in Table 5
Write an 1?to TXQCR[2] reg
to issue a transmit command (auto-
enqueue) to the TXQ. The TXQ will
transmit all data to the PHY port
Check if KSZ8851M TXQ
Memory size is available for these
transmit pkts?
(Read TXMIR Reg)
Write an 1? to RXQCR[3] reg to enable
TXQ write access, then Host starts
write transmit data (con tro l word, byt e
count and pkt data) to TXQ memory.
This is moving transmit data from Host
to KSZ8851M TXQ memory until all
pkts are finished
Write an 0?to RXQCR[3] reg to end
TXQ write access
Option to read ISR[14] reg, it indicates
that the TXQ has completed to transmit
all pkts to the PHY port, then
Write 1? to clear this bit
Yes
No
Write the total amount of TXQ buffer
space which is required for next
transmit total frames size in double-
word count in TXNTFSR[15:0] regist er
Set bit 1=1 in TXQCR register to
enable the TXQ memory available
monitor
Wait for interrupt
and check if the bit 6=1
(memory space available)
in ISR register
?
Yes No
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Receive Queue (RXQ) Frame Format
The frame format for the receive queue is shown in Table 9. The first word contains the status inform ation for the frame
received. The second word is the total number of bytes of the RX frame. Following that is the packet data area. The
packet data area holds the frame itself. It includes the CRC checksum.
Packet Memory
Address Offset Bit 15 Bit 0
2nd Byte 1st Byte
0 Status Word (High byte and low byte need to swap in Big-
Endian mode. Also see description in RXFHSR register)
2 Byte Count (High byte and low byte need to swap in Big-
Endian mode. Also see description in RXFHBCR register)
4 - up Receive Packet Data
(maximum size is 2000)
Table 9. Frame Format for Receive Queue
Frame Receiving Path Operation in RXQ
This section describes the typical register settings for receiving packets from KSZ8851M to host processor with generic
bus interface. User can use the default value for most of the receive registers. The following Table 10 describes all
registers which need to be set and used for receiving single or multiple frames.
Register Name[bit](offset) Description
RXCR1(0x74)
RXCR2(0x76)
Set receive control function as below:
Set RXCR1[10] to enable receiving flow control. Set RXCR1[0] to enable receiving block operation.
Set receive checksum check for ICMP, UDP, TCP and IP packet.
Set receive address filtering scheme as shown in the Table 3.
RXFHSR[15:0](0x7C) This register (read only) indicates the current received frame header status information.
RXFHBCR[11:0](0x7E) This register (read only) indicates the current received frame header byte count information.
RXQCR[12:3](0x82) Set RXQ control function as below:
Set bit 3 to start DMA access from host CPU either read (receive frame data) or write (transmit data
frame). Set bit 4 to automatically enable RXQ frame buffer dequeue. Set bit 5 to enable RX frame count
threshold and read bit 10 for status. Set bit 6 to enable RX data byte count threshold and read bit 11 for
status. Set bit 7 to enable RX frame duration timer threshold and read bit 12 for status. Set bit 9 enable
RX IP header two-byte offset.
RXFDPR[14](0x86) Set bit 14 to enable RXQ address register increments automatically on accesses to the data register.
RXDTTR[15:0](0x8C) To program received frame duration timer value. When Rx frame duration in RXQ exceeds this
threshold in 1µS interval count and bit 7 of RXQCR register is set to 1, the KSZ8851M will generate RX
interrupt in ISR[13] and indicate the status in RXQCR[12].
RXDBCTR[15:0](0x8E) To program received data byte count value. When the number of received bytes in RXQ exceeds this
threshold in byte count and bit 6 of RXQCR register is set to 1, the KSZ8851M will generate RX
interrupt in ISR[13] and indicate the status in RXQCR[11].
IER[13](0x90) Set bit 13 to enable receive interrupt in Interrupt Enable Register.
ISR[15:0](0x92) Write 1 (0xFFFF) to clear all interrupt status bits after interrupt occurred in Interrupt Status Register.
RXFCTR[15:8](0x9C) Rx frame count read only. To indicate the total received frame in RXQ frame buffer when receive
interrupt (bit 13 in ISR) occurred.
RXFCTR[7:0](0x9C) To program received frame count value. When the number of received frames in RXQ exceeds this
threshold value and bit 5 of RXQCR register is set to 1, the KSZ8851M will generate RX interrupt in
ISR[13] and indicate the status in RXQCR[10].
Table 10. Registers Setting for Receive Function Block
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Driver Routine for Receive Packet from KSZ8851M to Host Processor
The software driver receives data packet frames from the KSZ8851M device either as a result of polling or an interrupt
based service. When an interrupt is received, the OS invokes the interrupt service routine that is in the interrupt vector
table.
If your system has OS support, to m inimize interrupt lock out time, the interrupt s ervice routine should handle at interrupt
level on ly those tasks that require m inimum execution time, such as error checking or device status change. The routine
should queue all the time-consuming work to transfer the packet from the KSZ8851M RXQ into system memory at task
level. The following Figure 10 shows the step-by-step for receive packets from KSZ8851M to host processor.
Note: Each D MA read operation f rom the hos t CPU to read RX Q fram e buffer, the first read data ( byte in 8-bit bus m ode,
word in 16-bit bus mode and double word in 32-bit bus mode) is dummy data and must be discarded by host CPU.
Afterward, host C PU must read each frame data to align with double word boundary at end. For exam ple, the host CPU
has to read up to 68 bytes if received frame size is 65 bytes.
Figure 10. Host RX Single or Multiple Frames in Auto-Dequeue Flow Diagram
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In order to read received frames from RXQ without error, the software driver must use following steps:
1. When receive interrupt occurred and software driver writes “1” to clear the RX interrupt in ISR register; the
KSZ8851 will update Receive Frame Counter (RXFCTR) Register for this interrupt.
2. When software driver reads back Receive Frame Count (RXFCTR) Register; the KSZ8851 will update both
Receive Frame Header Status and Byte Count Registers (RXFHSR/RXFHBCR).
3. When software driver reads back both Receive Frame Header Status and Byte Count Registers
(RXFHSR/RXFHBCR); the KSZ8851 will update next receive frame header status and byte count registers
(RXFHSR/RXFHBCR).
EEPROM Interface
It is opti ona l in the K SZ8851M to use an ex ternal EE P RO M. In the c ase that an E EPROM is not used, the E EEN pin mus t
be tied Low or floating .
An externa l ser ia l EEPROM with a st an dard mic rowir e bus interface is us ed f or non-v olati le s tor ag e of inf ormation suc h as
the host MAC address and default configuration setting for 8-bit or 16-bit bus width. The KSZ8851M can detect if the
EEPROM is a 1KB (93 C46) or 4KB (93C66) EEPRO M device (the 93C46 and the 93C66 are t ypical EEPROM devices).
The EEPROM must be organized as 16-bit mode.
If the EEEN p in is pul led high, then th e KSZ8851 M perf orms an autom atic read o f the external EEPROM words 0H to 6H
after the d e-ass ertio n of Re set. T he EEPRO M val ues are plac ed in cer tai n host-a cces sible reg isters . EE PROM r ead/wr ite
functions can also be performed by software read/writes to the EEPCR (0x22) registers.
The KSZ8851M EEPROM format is given in Table 11.
WORD 15 8 7 0
0H Reserved
1H Host MAC Address Byte 2 Host MAC Address Byte 1
2H Host MAC Address Byte 4 Host MAC Address Byte 3
3H Host MAC Address Byte 6 Host MAC Address Byte 5
4H – 5H Reserved
6H ConfigParam (see Table 12)
7H-3FH Not used for KSZ8851M (available for user to use)
Table 11. KSZ8851M EEPROM Format
The format for ConfigParam is shown in Table 12.
Bit Bit Name Description
15 - 1 Reserved Reserved
0 ASYN_8bit
Async 8-bit bus select
1= bus is configured for 16-bit width
0= bus is configured for 8-bit width
This bit is shown in either bit 7 or bit 6 of CCR register
The KSZ8851-32MQL 32-bit device does not care this bit setting
Table 12. ConfigParam Word in EEPROM Format
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Loopback Support
The KSZ8851M provides two loopback modes, one is Near-end (Remote) loopback to support for remote diagnostic of
failure at line side, and the other is Far-end (Local) loopback to support for local diagnostic of failure at host side. In
loopback mode, the speed at the PHY port will be set to 100BASE-TX full-duplex mode.
Near-end (Remote) Loopback
Near-end (Remote) loopback is conducted at PHY port 1 of the KSZ8851M. The loopback path starts at the PHY port’s
receive inputs (RXP1/RXM1), wraps around at the same PHY port’s PMD/PMA, and ends at the PHY port’s transmit
outputs (TXP1/TXM1).
Bit [9] of regis t er P1 SCL M D ( 0xF 4) is us ed to ena bl e near -en d loopbac k. The po r ts 1 near- en d lo opb ac k path is i llus tr a ted
in the following Figure 11.
Far-end (Local) Loopback
Far-end (Local) loopback is conducted at Host of the KSZ8851M. The loopback path starts at the host port’s transmit
inputs (Tx data), wraps around at the PHY port’s PMD/PMA, and ends at the host port’s receive outputs (Rx data)
Bit [14] of register P1MBCR (0xE4) is used to enable far-end loopback at host side. The host far-end loopback path is
illustrated in the following Figure 11.
Figure 11. PHY Port 1 Near-end (Remote) and Host Far-end (Local) Loopback Paths
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CPU Interface I/O Registers
The KSZ8851M provides an SRAM-like asynchronous bus interface for the CPU to access its internal I/O registers. I/O
registers serve as the address that the microprocessor uses when communicating with the device. This is used for
configuring operational settings, reading or writing control, status information, and transferring packets. The KSZ8851M
can be programmed to interface with either Big-Endian or Little-Endian processor.
I/O Registers
The following I/O Space Mapping Tables app ly to 8-, 16- or 32-bit bus interface. Depending upon the bus interface used
and byte enable signals (BE[3:0]N control byte access input pins), each I/O access can be performed the following
operations as an 8-bit for 256 address locations, 16-bit for 128 address locations or 32-bit for 64 address locations.
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Internal I/O Registers Space Mapping
I/O Register Offset Location
32-Bit 16-Bit 8-Bit
Register
Name Default
Value Description
0x00 - 0x01 0x00
0x01
0x00
to
0x03 0x02 - 0x03 0x02
0x03
Reserved Don’t care None
0x04 - 0x05 0x04
0x05 Reserved Don’t care
None
0x04
to
0x07 0x06 - 0x07 0x06
0x07 BESR 0x0000
Bus Error Status Register [7:0]
Bus Error Status Register [15:8]
0x08 - 0x09 0x08
0x09 CCR Read only
Chip Configuration Register [7:0]
Chip Configuration Register [15:8]
0x08
to
0x0B 0x0A - 0x0B 0x0A
0x0B Reserved Don’t care None
0x0C - 0x0D 0x0C
0x0D
0x0C
to
0x0F 0x0E - 0x0F 0x0E
0x0F
Reserved Don’t care None
0x10 - 0x11 0x10
0x11 MARL -
MAC Address Register Low [7:0]
MAC Address Register Low [15:8]
0x10
to
0x13 0x12 - 0x13 0x12
0x13 MARM -
MAC Address Register Middle [7:0]
MAC Address Register Middle [15:8]
0x14 - 0x15 0x14
0x15 MARH -
MAC Address Register High [7:0]
MAC Address Register High [15:8]
0x14
to
0x17 0x16 - 0x17 0x16
0x17 Reserved Don’t care None
0x18 - 0x19 0x18
0x19
0x18
to
0x1B 0x1A - 0x1B 0x1A
0x1B
Reserved Don’t care
None
0x1C - 0x1D 0x1C
0x1D
0x1C
to
0x1F 0x1E - 0x1F 0x1E
0x1F
Reserved Don’t care
None
0x20 - 0x21 0x20
0x21 OBCR 0x0000
On-Chip Bus Control Register [7:0]
On-Chip Bus Control Register [15:8]
0x20
to
0x23 0x22 - 0x23 0x22
0x23 EEPCR 0x0000
EEPROM Control Register [7:0]
EEPROM Control Register [15:8]
0x24 - 0x25 0x24
0x25 MBIR 0x1010
Memory BIST Info Register [7:0]
Memory BIST Info Register [15:8]
0x24
to
0x27 0x26 - 0x27 0x26
0x27 GRR 0x0000 Global Reset Register [7:0]
Global Reset Register [15:8]
0x28 - 0x29 0x28
0x29 Reserved Don’t care
None
0x28
to
0x2B 0x2A - 0x2B 0x2A
0x2B WFCR 0x0000
Wakeup Frame Control Register [7:0]
Wakeup Frame Control Register [15:8]
0x2C - 0x2D 0x2C
0x2D
0x2C
to
0x2F 0x2E - 0x2F 0x2E
0x2F
Reserved Don’t care
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I/O Register Offset Location
32-Bit 16-Bit 8-Bit
Register
Name Default
Value Description
0x30 - 0x31 0x30
0x31 WF0CRC0 0x0000
Wakeup Frame 0 CRC0 Register [7:0]
Wakeup Frame 0 CRC0 Register [15:8]
0x30
to
0x33 0x32 - 0x33 0x32
0x33 WF0CRC1 0x0000
Wakeup Frame 0 CRC1 Register [7:0]
Wakeup Frame 0 CRC1 Register [15:8]
0x34 - 0x35 0x34
0x35 WF0BM0 0x0000
Wakeup Frame 0 Byte Mask 0 Register [7:0]
Wakeup Frame 0 Byte Mask 0 Register [15:8]
0x34
to
0x37 0x36 - 0x37 0x36
0x37 WF0BM1 0x0000
Wakeup Frame 0 Byte Mask 1 Register [7:0]
Wakeup Frame 0 Byte Mask 1 Register [15:8]
0x38 - 0x39 0x38
0x39 WF0BM2 0x0000
Wakeup Frame 0 Byte Mask 2 Register [7:0]
Wakeup Frame 0 Byte Mask 2 Register [15:8]
0x38
to
0x3B 0x3A - 0x3B 0x3A
0x3B WF0BM3 0x0000
Wakeup Frame 0 Byte Mask 3 Register [7:0]
Wakeup Frame 0 Byte Mask 3 Register [15:8]
0x3C - 0x3D 0x3C
0x3D
0x3C
To
0x3F 0x3E - 0x3F 0x3E
0x3F
Reserved Don’t care None
0x40 - 0x41 0x40
0x41 WF1CRC0 0x0000
Wakeup Frame 1 CRC0 Register [7:0]
Wakeup Frame 1 CRC0 Register [15:8]
0x40
to
0x43 0x42 - 0x43 0x42
0x43 WF1CRC1 0x0000
Wakeup Frame 1 CRC1 Register [7:0]
Wakeup Frame 1 CRC1 Register [15:8]
0x44 - 0x45 0x44
0x45 WF1BM0 0x0000
Wakeup Frame 1 Byte Mask 0 Register [7:0]
Wakeup Frame 1 Byte Mask 0 Register [15:8]
0x44
to
0x47 0x46 - 0x47 0x46
0x47 WF1BM1 0x0000
Wakeup Frame 1 Byte Mask 1 Register [7:0]
Wakeup Frame 1 Byte Mask 1 Register [15:8]
0x48 - 0x49 0x48
0x49 WF1BM2 0x0000
Wakeup Frame 1 Byte Mask 2 Register [7:0]
Wakeup Frame 1 Byte Mask 2 Register [15:8]
0x48
to
0x4B 0x4A - 0x4B 0x4A
0x4B WF1BM3 0x0000
Wakeup Frame 1 Byte Mask 3 Register [7:0]
Wakeup Frame 1 Byte Mask 3 Register [15:8]
0x4C - 0x4D 0x4C
0x4D
0x4C
to
0x4F 0x4E - 0x4F 0x4E
0x4F
Reserved Don’t care None
0x50 - 0x51 0x50
0x51 WF2CRC0 0x0000
Wakeup Frame 2 CRC0 Register [7:0]
Wakeup Frame 2 CRC0 Register [15:8]
0x50
to
0x53 0x52 - 0x53 0x52
0x53 WF2CRC1 0x0000
Wakeup Frame 2 CRC1 Register [7:0]
Wakeup Frame 2 CRC1 Register [15:8]
0x54 - 0x55 0x54
0x55 WF2BM0 0x0000
Wakeup Frame 2 Byte Mask 0 Register [7:0]
Wakeup Frame 2 Byte Mask 0 Register [15:8]
0x54
to
0x57 0x56 - 0x57 0x56
0x57 WF2BM1 0x0000
Wakeup Frame 2 Byte Mask 1 Register [7:0]
Wakeup Frame 2 Byte Mask 1 Register [15:8]
0x58 - 0x59 0x58
0x59 WF2BM2 0x0000
Wakeup Frame 2 Byte Mask 2 Register [7:0]
Wakeup Frame 2 Byte Mask 2 Register [15:8]
0x58
to
0x5B 0x5A - 0x5B 0x5A
0x5B WF2BM3 0x0000 Wakeup Frame 2 Byte Mask 3 Register [7:0]
Wakeup Frame 2 Byte Mask 3 Register [15:8]
0x5C - 0x5D 0x5C
0x5D
0x5C
to
0x5F 0x5E - 0x5F 0x5E
0x5F
Reserved Don’t care None
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I/O Register Offset Location
32-Bit 16-Bit 8-Bit
Register
Name Default
Value Description
0x60 - 0x61 0x60
0x61 WF3CRC0 0x0000
Wakeup Frame 3 CRC0 Register [7:0]
Wakeup Frame 3 CRC0 Register [15:8]
0x60
to
0x63 0x62 - 0x63 0x62
0x63 WF3CRC1 0x0000
Wakeup Frame 3 CRC1 Register [7:0]
Wakeup Frame 3 CRC1 Register [15:8]
0x64 - 0x65 0x64
0x65 WF3BM0 0x0000
Wakeup Frame 3 Byte Mask 0 Register [7:0]
Wakeup Frame 3 Byte Mask 0 Register [15:8]
0x64
to
0x67 0x66 - 0x67 0x66
0x67 WF3BM1 0x0000
Wakeup Frame 3 Byte Mask 1 Register [7:0]
Wakeup Frame 3 Byte Mask 1 Register [15:8]
0x68 - 0x69 0x68
0x69 WF3BM2 0x0000
Wakeup Frame 3 Byte Mask 2 Register [7:0]
Wakeup Frame 3 Byte Mask 2 Register [15:8]
0x68
to
0x6B 0x6A - 0x6B 0x6A
0x6B WF3BM3 0x0000
Wakeup Frame 3 Byte Mask 3 Register [7:0]
Wakeup Frame 3 Byte Mask 3 Register [15:8]
0x6C - 0x6D 0x6C
0x6D
0x6C
to
0x6F 0x6E - 0x6F 0x6E
0x6F
Reserved Don’t care None
0x70 - 0x71 0x70
0x71 TXCR 0x0000
Transmit Control Register [7:0]
Transmit Control Register [15:8]
0x70
to
0x73 0x72 - 0x73 0x72
0x73 TXSR 0x0000
Transmit Status Register [7:0]
Transmit Status Register [15:8]
0x74 - 0x75 0x74
0x75 RXCR1 0x0800
Receive Control Register 1 [7:0]
Receive Control Register 1 [15:8]
0x74
to
0x77 0x76 - 0x77 0x76
0x77 RXCR2 0x0004
Receive Control Register 2 [7:0]
Receive Control Register 2 [15:8]
0x78 - 0x79 0x78
0x79 TXMIR 0x0000
TXQ Memory Information Register [7:0]
TXQ Memory Information Register [15:8]
0x78
to
0x7B 0x7A - 0x7B 0x7A
0x7B Reserved Don’t care
None
0x7C - 0x7D 0x7C
0x7D RXFHSR 0x0000
Receive Frame Header Status Register [7:0]
Receive Frame Header Status Register [15:8]
0x7C
to
0x7F 0x7E - 0x7F 0x7E
0x7F RXFHBCR 0x0000
Receive Frame Header Byte Count Register [7:0]
Receive Frame Header Byte Count Register [15:8]
0x80 - 0x81 0x80
0x81 TXQCR 0x0000
TXQ Command Register [7:0]
TXQ Command Register [15:8]
0x80
to
0x83 0x82 - 0x83 0x82
0x83 RXQCR 0x0000
RXQ Command Register [7:0]
RXQ Command Register [15:8]
0x84 - 0x85 0x84
0x85 TXFDPR 0x0000
TX Frame Data Pointer Register [7:0]
TX Frame Data Pointer Register [15:8]
0x84
to
0x87 0x86 - 0x87 0x86
0x87 RXFDPR 0x0000 RX Frame Data Pointer Register [7:0]
RX Frame Data Pointer Register [15:8]
0x88 - 0x89 0x88
0x89
0x88
to
0x8B 0x8A - 0x8B 0x8A
0x8B
Reserved Don’t care
None
0x8C - 0x8D 0x8C
0x8D RXDTTR 0x0000
RX Duration Timer Threshold Register [7:0]
RX Duration Timer Threshold Register [15:8]
0x8C
to
0x8F 0x8E - 0x8F 0x8E
0x8F RXDBCTR 0x0000
RX Data Byte Count Threshold Register [7:0]
RX Data Byte Count Threshold Register [15:8]
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I/O Register Offset Location
32-Bit 16-Bit 8-Bit
Register
Name Default
Value Description
0x90 - 0x91 0x90
0x91 IER 0x0000 Interrupt Enable Register [7:0]
Interrupt Enable Register [15:8]
0x90
to
0x93 0x92 - 0x93 0x92
0x93 ISR 0x0300
Interrupt Status Register [7:0]
Interrupt Status Register [15:8]
0x94 - 0x95 0x94
0x95
0x94
to
0x97 0x96 - 0x97 0x96
0x97
Reserved Don’t care None
0x98 - 0x99 0x98
0x99
0x98
to
0x9B 0x9A - 0x9B 0x9A
0x9B
Reserved Don’t care None
0x9C - 0x9D 0x9C
0x9D RXFCTR 0x0000
RX Frame Count & Threshold Register [7:0]
RX Frame Count & Threshold Register [15:8]
0x9C
to
0x9F 0x9E - 0x9F 0x9E
0x9F TXNTFSR 0x0000
TX Next Total Frames Size Register [7:0]
TX Next Total Frames Size Register [15:8]
0xA0 - 0xA1 0xA0
0xA1 MAHTR0 0x0000
MAC Address Hash Table Register 0 [7:0]
MAC Address Hash Table Register 0 [15:8]
0xA0
to
0xA3 0xA2 - 0xA3 0xA2
0xA3 MAHTR1 0x0000
MAC Address Hash Table Register 1 [7:0]
MAC Address Hash Table Register 1 [15:8]
0xA4 - 0xA5 0xA4
0xA5 MAHTR2 0x0000
MAC Address Hash Table Register 2 [7:0]
MAC Address Hash Table Register 2 [15:8]
0xA4
to
0xA7 0xA6 - 0xA7 0xA6
0xA7 MAHTR3 0x0000
MAC Address Hash Table Register 3 [7:0]
MAC Address Hash Table Register 3 [15:8]
0xA8 - 0xA9 0xA8
0xA9
0xA8
to
0xAB 0xAA - 0xAB 0xAA
0xAB
Reserved Don’t care
None
0xAC - 0xAD 0xAC
0xAD
0xAC
to
0xAF 0xAE - 0xAF 0xAE
0xAF
Reserved Don’t care None
0xB0 - 0xB1 0xB0
0xB1 FCLWR 0x0500
Flow Control Low Watermark Register [7:0]
Flow Control Low Watermark Register [15:8]
0xB0
to
0xB3 0xB2 - 0xB3 0xB2
0xB3 FCHWR 0x0300
Flow Control High Watermark Register [7:0]
Flow Control High Watermark Register [15:8]
0xB4 - 0xB5 0xB4
0xB5 FCOWR 0x0040
Flow Control Ov errun Watermark Register [7:0]
Flow Control Overrun Watermark Register [15:8]
0xB4
to
0xB7 0xB6 - 0xB7 0xB6
0xB7 Reserved Don’t care None
0xB8 - 0xB9 0xB8
0xB9
0xB8
to
0xBB 0xBA - 0xBB 0xBA
0xBB
Reserved Don’t care None
0xBC - 0xBD 0xBC
0xBD
0xBC
to
0xBF 0xBE - 0xBF 0xBE
0xBF
Reserved Don’t care None
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I/O Register Offset Location
32-Bit 16-Bit 8-Bit
Register
Name Default
Value Description
0xC0 - 0xC1 0xC0
0xC1 CIDER 0x8870
Chip ID and Enable Register [7:0]
Chip ID and Enable Register [15:8]
0xC0
to
0xC3 0xC2 - 0xC3 0xC2
0xC3 Reserved Don’t care None
0xC4 - 0xC5 0xC4
0xC5 Reserved Don’t care None
0xC4
to
0xC7 0xC6 - 0xC7 0xC6
0xC7 CGCR 0x0835
Chip Global Control Register [7:0]
Chip Global Control Register [15:8]
0xC8 - 0xC9 0xC8
0xC9 IACR 0x0000
Indirect Access Control Register [7:0]
Indirect Access Control Register [15:8]
0xC8
to
0xCB 0xCA - 0xCB 0xCA
0xCB Reserved Don’t care None
0xCC - 0xCD 0xCC
0xCD
0xCC
to
0xCF 0xCE - 0xCF 0xCE
0xCF
Reserved Don’t care None
0xD0 - 0xD1 0xD0
0xD1 IADLR 0x0000
Indirect Access Data Low Register [7:0]
Indirect Access Data Low Register [15:8]
0xD0
to
0xD3 0xD2 - 0xD3 0xD2
0xD3 IADHR 0x0000
Indirect Access Data High Register [7:0]
Indirect Access Data High Register [15:8]
0xD4 - 0xD5 0xD4
0xD5 PMECR 0x0080 Power Management Event Control Register [7:0]
Power Management Event C ontrol Register [15:8]
0xD4
to
0xD7 0xD6 - 0xD7 0xD6
0xD7 GSWUTR 0X080C
Go-Sleep & W ake-Up Time Register [7:0]
Go-Sleep & W ake-Up Time Register [15:8]
0xD8 - 0xD9 0xD8
0xD9 PHYRR 0x0000
PHY Reset Register [7:0]
PHY Reset Register [15:8]
0xD8
to
0xDB 0xDA - 0xDB 0xDA
0xDB Reserved Don’t care None
0xDC - 0xDD 0xDC
0xDD
0xDC
to
0xDF 0xDE - 0xDF 0xDE
0xDF
Reserved Don’t care None
0xE0 - 0xE1 0xE0
0xE1
0xE0
to
0xE3 0xE2 - 0xE3 0xE2
0xE3
Reserved Don’t care None
0xE4 - 0xE5 0xE4
0xE5 P1MBCR 0x3120
PHY 1 MII-Register Basic Control Register [7:0]
PHY 1 MII-Register Basic Control Register [15:8]
0xE4
to
0xE7 0xE6 - 0xE7 0xE6
0xE7 P1MBSR 0x7808
PHY 1 MII-Register Basic Status Register [7:0]
PHY 1 MII-Register Basic Status Register [15:8]
0xE8 - 0xE9 0xE8
0xE9 PHY1ILR 0x1430
PHY 1 PHY ID Low Register [7:0]
PHY 1 PHY ID Low Register [15:8]
0xE8
to
0xEB 0xEA - 0xEB 0xEA
0xEB PHY1IHR 0x0022
PHY 1 PHY ID High Register [7:0]
PHY 1 PHY ID High Register [15:8]
PHY 1 Aut o-Negotiation Adv ertisement R egister [7:0 ]
0xEC - 0xED 0xEC
0xED P1ANAR 0x05E1
PHY 1 Auto-Negotiation Advertisement
Regi ster [ 15: 8]
PHY 1 Auto-Negotiation Link Partner Ability Register [7:0]
0xEC
to
0xEF 0xEE - 0xEF 0xEE
0xEF P1ANLPR 0x0001
PHY 1 Auto-Negotiation Link Partner Ability Register [15:8]
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I/O Register Offset Location
32-Bit 16-Bit 8-Bit
Register
Name Default
Value Description
0xF0 - 0xF1 0xF0
0xF1
0xF0
to
0xF3 0xF2 - 0xF3 0xF2
0xF3
Reserved Don’t care None
0xF4 - 0xF5 0xF4
0xF5 P1SCLMD 0x0000 Port 1 PHY Special Control/Status, LinkM D® [7:0]
Port 1 PHY Special Control/Status, LinkMD® [15:8]
0xF4
to
0xF7 0xF6 - 0xF7 0xF6
0xF7 P1CR 0x00FF
Port 1 Control Register [7:0]
Port 1 Control Register [15:8]
0xF8 - 0xF9 0xF8
0xF9 P1SR 0x8080
Port 1 Status Register [7:0]
Port 1 Status Register [15:8]
0xF8
to
0xFB 0xFA - 0xFB 0xFA
0xFB Reserved Don’t care None
0xFC - 0xFD 0xFC
0xFD
0xFC
to
0xFF 0xFE - 0xFF 0xFE
0xFF
Reserved Don’t care None
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Register Map: MAC, PHY and QMU
Do not write to bit values or to registers defined as Reserved. Manipulating reserved bits or registers causes
unpredictable and often fatal results. If the user wants to write to these reserved bits, the user has to read back these
reserved bits (RO or RW) first, then “OR” with the read value of the reserved bits and write back to these reserved bits.
Bit Type Definition
RO = Read only.
WO = Write only.
RW = Read/Write.
W1C = Write 1 to Clear (writing an “1” to clear this bit).
0x00 – 0x05: Reserved
Bus Error Status Register (0x06 – 0x07): BESR
This register flags the different kinds of errors on the host bus.
Bit Default Value R/W Description
15 0 RO
(W1C) IBEC Illegal Byte Enable Combination
1: illegal byte enable combination occurs. The illegal combination value can be
found from bit 14 to bit 11.
0: legal byte enable combination.
Write 1 to clear this bit.
14-11 - RO IBECV Illegal Byte Enable Combination Value
Bit 14: byte enable 3.
Bit 13: byte enable 2.
Bit 12: byte enable 1.
Bit 11: byte enable 0.
This value is valid only when bit 15 is set to 1.
10-0 - RO Reserved.
Chip Configuration Register (0x08 – 0x09): CCR
This register indicates the chip configuration mode based on strapping and bonding options
Bit Default Value R/W Description
15-11 - RO Reserved.
10 - RO Bus Endian mode
The EESK (pin 29) value is latched into this bit druing power-up/reset.
0: Bus in Big Endian mode, 1: Bus in Little Endian mode.
9 - RO
EEPROM presence
The EEEN (pin 26) value is latched into this bit druing power-up/reset.
0: No external EEPROM, 1: Use external EEPROM.
8 0 RO
Reserved.
7 - RO
8-Bit data bus width
This bit value is loaded from either EEPROM or EEDI (pin 30, without EEPROM).
0: Not in 8-bit bus mode operation, 1: In 8-bit bus mode operation.
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Bit Default Value R/W Description
6 - RO
16-Bit data bus width
This bit value is loaded from either EEPROM or EEDI (pin 30, without EEPROM)
0: Not in 16-bit bus mode operation, 1: In 16-bit bus mode operation.
5 - RO
32-Bit data bus width
This bit is set when uses KSZ8851-32MQL device.
0: Not in 32-bit bus mode operation, 1: In 32-bit bus mode operation.
4 0 RO
Reserved.
3 - RO
128-Pin Chip Package
To indicate chip pack age is 12 8-pin.
0: No, 1: Yes.
2 0 RO
Reserved.
1 0 RO
Reserved.
0 0 RO
Reserved.
0x0A – 0x0F: Reserved
Host MAC Address Registers: MARL, MARM and MARH
These Host MAC address registers are loaded starting at word location 0x1 of the EEPROM upon hardware reset. The
software driver can read or write these registers value, but it will not modify the original Host MAC address value in the
EEPROM. These six bytes of Host MAC address in external EEPROM are loaded to these three registers as mapping
below:
MARL[15 :0] = EE PROM 0x 1( MAC Byte 2 and 1)
MARM[15 :0] = EE PROM 0x2( MAC Byte 4 and 3)
MARH[15: 0] = EEPRO M 0x3( MAC Byte 6 and 5)
The Host MAC address is used to define the individual destination address that the KSZ8851M responds to when
receiving frames. Network addresses are generally expressed in the form of 01:23:45:67:89:AB, where the bytes are
received from left to right, and the bits within each byte are received from right to left (LSB to MSB). For example, the
actual transmitted and received bits are on the order of 10000000 11000100 10100010 11100110 10010001 11010101.
These three registers value for Host MAC address 01:23:45:67:89:AB will be held as below:
MARL[15 :0] = 0x8 9A B
MARM[15:0] = 0x4567
MARH[15: 0] = 0x0123
Host MAC Address Register Low (0x10 – 0x11): MARL
The following table shows the register bit fields for Low word of Host MAC address.
Bit Default Value R/W Description
15-0 - RW MARL MAC Address Low
The least significant word of the MAC address.
Host MAC Address Register Middle (0x12 – 0x13): MARM
The following table shows the register bit fields for middle word of Host MAC address.
Bit Default Value R/W Description
15-0 - RW MARM MAC Address Middle
The middle word of the MAC address.
Host MAC Address Register High (0x14 – 0x15): MARH
The following table shows the register bit fields for high word of Host MAC address.
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Bit Default Value R/W Description
15-0 - RW MARH MAC Address High
The Most significant word of the MAC address.
0x16 – 0x1F: Reserved
On-Chip Bus Control Register (0x20 – 0x21): OBCR
This register controls the on-chip bus clock speed for the KSZ8851M. The default of the on-chip bus clock speed is
125MHz. W hen the external host CPU is running at a higher clock rate, the on-chip bus should be adjusted for the best
performance.
Bit Default Value R/W Description
15-7 - RW Reserved.
6 0 RW Output Pin Drive Strength
Bi-directional or output pad drive strength selection.
0: 8 mA
1: 16 mA
5-3 - RW Reserved.
2 0 RW On-Chip Bus Clock Selection
0: 125MHz (default setting is divided by 1, Bit[1:0]=00)
1: NA (reserved)
1-0 0x0 RW On-Chip Bus Clock Divider Selection
00: Divided by 1.
01: Divided by 2.
10: Divided by 3.
11: NA (reserved).
For example to contol the bus clock speed as below:
If Bit 2 = 0 and this value is set 00 to select 125MHz.
If Bit 2 = 0 and this value is set 01 to select 62.5MHz.
EEPROM Control Register (0x22 – 0x23): EEPCR
To support an external EEPROM, tie the EEPROM Enable (EEEN) pin to High; otherwise, tie it to Low. If an external
EEPROM is not used, the software programs the host MAC address. If an EEPROM is used in the design (EEPROM
Enable pin to High), the chip host MAC address is loaded from the EEPROM immediately after reset. The KSZ8851M
allows the software to access (read and write) the EEPROM directly; that is, the EEPROM access timing can be fully
controlled by the software if the EEPROM Software Access bit is set.
Bit Default Value R/W Description
15-5 - RO Reserved.
4 0 RW EESA EEPROM Software Access
1: enable software to access EEPROM through bit 3 to bit 0.
0: disable software to access EEPROM.
3 - RO EESB EEPROM Status Bit
Data Receive from EEPROM. This bit directly reads the EEDI pin.
2-0 0x0 RW EECB EEPROM Control Bits
Bit 2: Data Transmit to EEPROM. This bit directly controls the device’s EEDO pin.
Bit 1: Serial Clock. This bit directly controls the device’s EESK pin.
Bit 0: Chip Select for EEPROM. This bit directly controls the device’s EECS pin.
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Memory BIST Info Register (0x24 – 0x25): MBIR
This register indicates the build-in self test result for both TX and RX memories after power-up/reset.
Bit Default Value R/W Description
15-13 0x0 RO Reserved.
12 - RO TXMBF TX Memory BIST Test Finish
When set, it indicates the Memory Built In Self Test completion for the TX
Memory.
11 - RO TXMBFA TX Memory BIST Test Fail
When set, it indicates the TX Memory Built In Self Test has failed.
10-8 - RO TXMBFC TX Memory BIST Test Fail Count
To indicate the TX Memory Built In Self Test failed count
7-5 - RO Reserved.
4 - RO RXMBF RX Memory Bist Finish
When set, it indicates the Memory Built In Self Test completion for the RX
Memory.
3 - RO RXMBFA RX Memory Bist Fail
When set, it indicates the RX Memory Built In Self Test has failed.
2-0 - RO RXMBFC RX Memory BIST Test Fail Count
To indicate the RX Memory Built In Self Test failed count.
Global Reset Register (0x26 – 0x27): GRR
This register controls the global and QMU reset functions with information programmed by the CPU.
Bit Default Value R/W Description
15-2 0x0000 RO Reserved.
1 0 RW QMU Module Soft Reset
1: Software reset is active to clear both TXQ and RXQ memories.
0: Software reset is inactive.
QMU software reset will flush out all TX/RX packet data inside the TXQ and RXQ
memories and reset all QMU registers to default value.
0 0 RW Global Soft Reset
1: Software reset is active.
0: Software reset is inactive.
Global software reset will affect PHY, MAC, QMU, DMA, and the switch core, all
registers value are set to default value.
0x28 – 0x29: Reserved
Wakeup Frame Control Register (0x2A – 0x2B): WFCR
This register holds control information programmed by the CPU to control the wake up frame function.
Bit Default Value R/W Description
15-8 0x00 RO Reserved.
7 0 RW MPRXE
Magic Packet RX Enable
When set, it enables the magic packet pattern detection.
When reset, the magic packet pattern detection is disabled.
6-4 0x0 RO Reserved.
3 0 RW WF3E
Wake up Frame 3 Enable
When set, it enables the Wake up frame 3 pattern detection.
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Bit Default Value R/W Description
When reset, the Wake up frame 3 pattern detection is disabled.
2 0 RW WF2E
Wake up Frame 2 Enable
When set, it enables the Wake up frame 2 pattern detection.
When reset, the Wake up frame 2 pattern detection is disabled.
1 0 RW WF1E
Wake up Frame 1 Enable
When set, it enables the Wake up frame 1 pattern detection.
When reset, the Wake up frame 1 pattern detection is disabled.
0 0 RW WF0E
Wake up Frame 0 Enable
When set, it enables the Wake up frame 0 pattern detection.
When reset, the Wake up frame 0 pattern detection is disabled.
0x2C – 0x2F: Reserved
Wakeup Frame 0 CRC0 Register (0x30 – 0x31): WF0CRC0
This register contains the expected CRC values of the Wake up frame 0 pattern.
The value of the CRC calculated is based on the IEEE 802.3 Ethernet standard; it is taken over the bytes specified in
the wake up byte mask registers.
Bit Default Value R/W Description
15-0 0x0000 RW WF0CRC0
Wake up Frame 0 CRC (lower 16 bits)
The expected CRC value of a Wake up frame 0 pattern.
Wakeup Frame 0 CRC1 Register (0x32 – 0x33): WF0CRC1
This register contains the expected CRC values of the Wake up frame 0 pattern.
The value of the CRC calculated is based on the IEEE 802.3 Ethernet standard; it is taken over the bytes specified in
the wake up byte mask registers.
Bit Default Value R/W Description
15-0 0x0000 RW WF0CRC1
Wake up Frame 0 CRC (upper 16 bits).
The expected CRC value of a Wake up frame 0 pattern.
Wakeup Frame 0 Byte Mask 0 Register (0x34 – 0x35): WF0BM0
This register contains the first 16 bytes mask values of the Wake up frame 0 pattern. Setting bit 0 selects the first byte
of the Wake up frame 0, setting bit 15 selects the 16th byte of the Wake up frame 0.
Bit Default Value R/W Description
15-0 0x0000 RW WF0BM0
Wake up Frame 0 Byte Mask 0
The first 16 bytes mask of a Wake up frame 0 pattern.
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Wakeup Frame 0 Byte Mask 1 Register (0x36 – 0x37): WF0BM1
This register contains the next 16 bytes mask values of the Wake up frame 0 pattern. Setting bit 0 selects the 17th byte
of the Wake up frame 0. Setting bit 15 selects the 32nd byte of the Wake up frame 0.
Bit Default Value R/W Description
15-0 0x0000 RW WF0BM1
Wake up Frame 0 Byte Mask 1.
The next 16 bytes mask covering bytes 17 to 32 of a Wake up frame 0 pattern.
Wakeup Frame 0 Byte Mask 2 Register (0x38 – 0x39): WF0BM2
This register contains the n ext 16 bytes m ask values of the Wake up frame 0 pattern. Setting bit 0 se lects the 33rd byte
of the Wake up frame 0. Setting bit 15 selects the 48th byte of the Wake up frame 0.
Bit Default Value R/W Description
15-0 0x0000 RW WF0BM2
Wake-up Frame 0 Byte Mask 2.
The next 16 bytes mask covering bytes 33 to 48 of a Wake-up frame 0 pattern.
Wakeup Frame 0 Byte Mask 3 Register (0x3A – 0x3B): WF0BM3
This register contains the last 16 bytes mask values of the Wake up frame 0 pattern. Setting bit 0 selects the 49th byte
of the Wake up frame 0. Setting bit 15 selects the 64th byte of the Wake up frame 0.
Bit Default Value R/W Description
15-0 0x0000 RW WF0BM3
Wake-up Frame 0 Byte Mask 3.
The last 16 bytes mask covering bytes 49 to 64 of a Wake-up frame 0 pattern.
0x3C – 0x3F: Reserved
Wakeup Frame 1 CRC0 Register (0x40 – 0x41): WF1CRC0
This register contains the expected CRC values of the Wake up frame 1 pattern.
The value of the CRC calculated is based on the IEEE 802.3 Ethernet standard; it is taken over the bytes specified in
the wake up byte mask registers.
Bit Default Value R/W Description
15-0 0x0000 RW WF1CRC0
Wake-up frame 1 CRC (lower 16 bits).
The expected CRC value of a Wake-up frame 1 pattern.
Wakeup Frame 1 CRC1 Register (0x42 – 0x43): WF1CRC1
This register contains the expected CRC values of the Wake up frame 1 pattern.
The value of the CRC calculated is based on the IEEE 802.3 Ethernet standard, it is taken over the bytes specified in
the wake up byte mask registers.
Bit Default Value R/W Description
15-0 0x0000 RW WF1CRC1
Wake-up frame 1 CRC (upper 16 bits).
The expected CRC value of a Wake-up frame 1 pattern.
Wakeup Frame 1 Byte Mask 0 Register (0x44 – 0x45): WF1BM0
This register contains the first 16 bytes mask values of the Wake up frame 1 pattern. Setting bit 0 selects the first byte
of the Wake up frame 1, setting bit 15 selects the 16th byte of the Wake up frame 1.
Bit Default Value R/W Description
15-0 0x0000 RW
WF1BM0
Wake-up frame 1 Byte Mask 0.
The first 16 bytes mask of a Wake-up frame 1 pattern.
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Wakeup Frame 1 Byte Mask 1 Register (0x46 – 0x47): WF1BM1
This register contains the next 16 bytes mask values of the Wake up frame 1 pattern. Setting bit 0 selects the 17th byte
of the Wake up frame 1. Setting bit 15 selects the 32nd byte of the Wake up frame 1.
Bit Default Value R/W Description
15-0 0x0000 RW
WF1BM1
Wake-up frame 1 Byte Mask 1.
The next 16 bytes mask covering bytes 17 to 32 of a Wake-up frame 1 pattern.
Wakeup Frame 1 Byte Mask 2 Register (0x48 – 0x49): WF1BM2
This register contains the n ext 16 bytes m ask values of the Wake up frame 1 pattern. Setting bit 0 se lects the 33rd byte
of the Wake up frame 1. Setting bit 15 selects the 48th byte of the Wake up frame 1.
Bit Default Value R/W Description
15-0 0x0000 RW
WF1BM2
Wake-up frame 1 Byte Mask 2.
The next 16 bytes mask covering bytes 33 to 48 of a Wake-up frame 1 pattern.
Wakeup Frame 1 Byte Mask 3 Register (0x4A – 0x4B): WF1BM3
This register contains the last 16 bytes mask values of the Wake up frame 1 pattern. Setting bit 0 selects the 49th byte
of the Wake up frame 1. Setting bit 15 selects the 64th byte of the Wake up frame 1.
Bit Default Value R/W Description
15-0 0x0000 RW
WF1BM3
Wake-up frame 1 Byte Mask 3.
The last 16 bytes mask covering bytes 49 to 64 of a Wake-up frame 1 pattern.
0x4C – 0x4F: Reserved
Wakeup Frame 2 CRC0 Register (0x50 – 0x51): WF2CRC0
This register contains the expected CRC values of the Wake up frame 2 pattern.
The value of the CRC calculated is based on the IEEE 802.3 Ethernet standard, it is taken over the bytes specified in
the wake up byte mask registers.
Bit Default Value R/W Description
15-0 0x0000 RW
WF2CRC0
Wake-up frame 2 CRC (lower 16 bits). The expected CRC value of a Wake-up frame 2
pattern.
Wakeup Frame 2 CRC1 Register (0x52 – 0x53): WF2CRC1
This register contains the expected CRC values of the wake-up frame 2 pattern.
The value of the CRC calculated is based on the IEEE 802.3 Ethernet standard, it is taken over the bytes specified in
the wake up byte mask registers.
Bit Default Value R/W Description
15-0 0x0000 RW
WF2CRC1
Wake-up frame 2 CRC (upper 16 bits). The expected CRC value of a Wake-up frame 2
pattern.
Wakeup Frame 2 Byte Mask 0 Register (0x54 – 0x55): WF2BM0
This register contains the first 16 bytes mask values of the Wake up frame 2 pattern. Setting bit 0 selects the first byte
of the Wake up frame 2, setting bit 15 selects the 16th byte of the Wake up frame 2.
Bit Default Value R/W Description
15-0 0x0000 RW
WF2BM0
Wake-up frame 2 Byte Mask 0. The first 16 bytes mask of a Wake-up frame 2 pattern.
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Wakeup Frame 2 Byte Mask 1 Register (0x56 – 0x57): WF2BM1
This register contains the next 16 bytes mask values of the Wake up frame 2 pattern. Setting bit 0 selects the 17th byte
of the Wake up frame 2. Setting bit 15 selects the 32nd byte of the Wake up frame 2.
Bit Default Value R/W Description
15-0 0x0000 RW
WF2BM1
Wake-up frame 2 Byte Mask 1. The next 16 bytes mask covering bytes 17 to 32 of a
Wake-up frame 2 pattern.
Wakeup Frame 2 Byte Mask 2 Register (0x58 – 0x59): WF2BM2
This register contains the n ext 16 bytes m ask values of the Wake up frame 2 pattern. Setting bit 0 se lects the 33rd byte
of the Wake up frame 2. Setting bit 15 selects the 48th byte of the Wake up frame 2.
Bit Default Value R/W Description
15-0 0 RW
WF2BM2
Wake-up frame 2 Byte Mask 2. The next 16 bytes mask covering bytes 33 to 48 of a
Wake-up frame 2 pattern.
Wakeup Frame 2 Byte Mask 3 Register (0x5A – 0x5B): WF2BM3
This register contains the last 16 bytes mask values of the Wake up frame 2 pattern. Setting bit 0 selects the 49th byte
of the Wake up frame 2. Setting bit 15 selects the 64th byte of the Wake up frame 2.
Bit Default Value R/W Description
15-0 0 RW
WF2BM3
Wake-up frame 2 Byte Mask 3. The last 16 bytes mask covering bytes 49 to 64 of a
Wake-up frame 2 pattern.
0x5C – 0x5F: Reserved
Wakeup Frame 3 CRC0 Register (0x60 – 0x61): WF3CRC0
This register contains the expected CRC values of the Wake up frame 3 pattern. The value of the CRC calculated is
based on the IEEE 802.3 Ethernet standard, it is taken over the bytes specified in the wake-up byte mask registers.
Bit Default Value R/W Description
15-0 0 RW
WF3CRC0
Wake-up frame 3 CRC (lower 16 bits). The expected CRC value of a Wake up frame 3
pattern.
Wakeup Frame 3 CRC1 Register (0x62 – 0x63): WF3CRC1
This register contains the expected CRC values of the Wake up frame 3 pattern. The value of the CRC calculated is
based on the IEEE 802.3 Ethernet standard, it is taken over the bytes specified in the wake-up byte mask registers.
Bit Default Value R/W Description
15-0 0 RW
WF3CRC1
Wake-up frame 3 CRC (upper 16 bits). The expected CRC value of a W ake u p frame 3
pattern.
Wakeup Frame 3 Byte Mask 0 Register (0x64 – 0x65): WF3BM0
This register contains the first 16 bytes mask values of the Wake up frame 3 pattern. Setting bit 0 selects the first byte
of the Wake up frame 3, setting bit 15 selects the 16th byte of the Wake up frame 3.
Bit Default Value R/W Description
15-0 0 RW
WF3BM0
Wake up Frame 3 Byte Mask 0. The first 16 byte mask of a Wake up frame 3 pattern.
Wakeup Frame 3 Byte Mask 1 Register (0x66 – 0x67): WF3BM1
This register contains the next 16 bytes mask values of the Wake up frame 3 pattern. Setting bit 0 selects the 17th byte
of the Wake up frame 3. Setting bit 15 selects the 32nd byte of the Wake up frame 3.
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Bit Default Value R/W Description
15-0 0 RW
WF3BM1
Wake up Frame 3 Byte Mask 1. The next 16 bytes mask covering bytes 17 to 32 of a
Wake up frame 3 pattern.
Wakeup Frame 3 Byte Mask 2 Register (0x68 – 0x69): WF3BM2
This register contains the n ext 16 bytes m ask values of the Wake up frame 3 pattern. Setting bit 0 se lects the 33rd byte
of the Wake up frame 3. Setting bit 15 selects the 48th byte of the Wake up frame 3.
Bit Default Value R/W Description
15-0 0 RW
WF3BM2
Wake up Frame 3 Byte Mask 2. The next 16 bytes mask covering bytes 33 to 48 of a
Wake up frame 3 pattern.
Wakeup Frame 3 Byte Mask 3 Register (0x6A – 0x6B): WF3BM3
This register contains the last 16 bytes mask values of the Wake up frame 3 pattern. Setting bit 0 selects the 49th byte
of the Wake up frame 3. Setting bit 15 selects the 64th byte of the Wake up frame 3.
Bit Default Value R/W Description
15-0 0 RW
WF3BM3
Wake up Frame 3 Byte Mask 3. The last 16 bytes mask covering bytes 49 to 64 of a
Wake up frame 3 pattern.
0x6C – 0x6F: Reserved
Transmit Control Register (0x70 – 0x71): TXCR
This register holds control information programmed by the CPU to control the QMU transmit module function.
Bit Default Value R/W Description
15-9 - RO
Reserved.
8 0x0 RW
TCGICMP Transmit Checksum Generation for ICMP
When this bit is set, The KSZ8851M is enabled to transmit ICMP frame (only for non-
fragment frame) checksum generation.
7 0x0 RO
Reserved.
6 0x0 RW
TCGTCP Transmit Checksum Generation for TCP
When this bit is set, The KSZ8851M is enabled to transmit TCP frame checksum
generation.
5 0x0 RW
TCGIP Transmit Checksum Generation for IP
When this bit is set, The KSZ8851M is enabled to transmit IP header checksum
generation.
4 0x0 RW
FTXQ Flush Transmit Queue
When this bit is set, The transmit queue memory is cleared and TX frame pointer is reset.
Note: Disable the TXE transmit enable bit[0] first before set this bit, then clear this bit to
normal operation.
3 0x0 RW
TXFCE Transmit Flow Control Enable
When this bit is set and the KSZ8851M is in full-duplex mode, flow control is enabled. The
KSZ8851M transmits a PAUSE frame when the Receive Buffer capacity reaches a
threshold level that will cause the buffer to overflow.
When this bit is set and the KSZ8851M is in half-duplex mode, back-pressure flow control
is enabled. When this bit is cleared, no transmit flow control is enabled.
2 0x0 RW
TXPE Transmit Padding Enable
When this bit is set, the KSZ8851M automatically adds a padding field to a packet shorter
than 64 bytes.
Note: Setting this bit requires enabling the add CRC feature (bit1=1) to avoid CRC errors
for the transmit packet.
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Bit Default Value R/W Description
1 0x0 RW
TXCE Transmit CRC Enable
When this bit is set, the KSZ8851M automatically adds a 32-bit CRC checksum field to
the end of a transmit frame.
0 0x0 RW
TXE Transmit Enable
When this bit is set, the transmit module is enabled and placed in a running state. When
reset, the transmit process is placed in the stopped state after the transmission of the
current frame is completed.
Transmit Status Register (0x72 – 0x73): TXSR
This register keeps the status of the last transmitted frame.
Bit Default Value R/W Description
15-14 0x0 RO Reserved.
13 0x0 RO
TXLC Transmit Late Collision
This bit is set when a transmit Late Collision occurs.
12 0x0 RO
TXMC Transmit Maximum Collision
This bit is set when a transmit Maximum Collision is reached.
11-6 - RO
Reserved.
5-0 - RO
TXFID Transmit Frame ID
This field identifies the transmitted frame. All of the transmit status information in this
register belongs to the frame with this ID.
Receive Control Register 1 (0x74 – 0x75): RXCR1
This register holds control information programmed by the CPU to control the receive function.
Bit Default Value R/W Description
15 0x0 RW
FRXQ Flush Receive Queue
When this bit is set, The receive queue memory is cleared and RX frame pointer is reset.
Note: Disable the RXE receive enable bit[0] first before set this bit, then clear this bit to
normal operation.
14 0x0 RW
RXUDPFCC Receive UDP Frame Checksum Check Enable
When this bit is set, the KSZ8851 will check for correct UDP checksum for incoming UDP
frames. Any received UDP frames with incorrect checksum will be discarded.
13 0x0 RW
RXTCPFCC Receive TCP Frame Checksum Check Enable
When this bit is set, the KSZ8851 will check for correct TCP checksum for incoming TCP
frames. Any received TCP frames with incorrect checksum will be discarded.
12 0x0 RW
RXIPFCC Receive IP Frame Checksum Check Enable
When this bit is set, the KSZ8851 will check for correct IP header checksum for incoming
IP frames. Any received IP header with incorrect checksum will be discarded.
11 0x1 RW
RXPAFMA Receive Physical Address Filtering with MAC Address Enable
When this bit is set, this bit enables the RX function to receive physical address that pass
the MAC address filtering mechanism (see Address Filtering Scheme in Table 3 for
detail).
10 0x0 RW
RXFCE Receive Flow Control Enable
When this bit is set and the KSZ8851M is in full-duplex mode, flow control is enabled, and
the KSZ8851M will acknowledge a PAUSE frame from the receive interface; i.e., the
outgoing packets are pending in the transmit buffer until the PAUSE frame control timer
expires. This field has no meaning in half-duplex mode and should be programmed to 0.
When this bit is cleared, flow control is not enabled.
9 0x0 RW
RXEFE Receive Error Frame Enable
W hen this bit is set, CRC error frames are allowed to be received into the RX queue.
When this bit is cleared, all CRC error frames are discarded.
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Bit Default Value R/W Description
8 0x0 RW
RXMAFMA Receive Multicast Address Filtering with MAC Address Enable
When this bit is set, this bit enables the RX function to receive multicast address that pass
the MAC address filtering mechanism (see Address Filtering Scheme in Table 3 for
detail).
7 0x0 RW
RXBE Receive Broadcast Enable
When this bit is set, the RX module receives all the broadcast frames.
6 0x0 RW
RXME Receive Multicast Enable
When this bit is set, the RX module receives all the multicast frames (including broadcast
frames).
5 0x0 RW
RXUE Receive Unicast Enable
When this bit is set, the RX module receives unicast frames that match the 48-bit Station
MAC address of the module.
4 0x0 RW
RXAE Receive All Enable
When this bit is set, the KSZ8851M receives all incoming frames, regardless of the
frame’s destination address (see Address Filtering Scheme in Table 3 for detail).
3-2 0x0 RW
Reserved
1 0x0 RW
RXINVF Receive Inverse Filtering
When this bit is set, the KSZ8851M receives function with address check operation in
inverse filtering mode (see Address Filtering Scheme in Table 3 for detail).
0 0x0 RW
RXE Receive Enable
When this bit is set, the RX block is enabled and placed in a running state.
When this bit is cleared, the receive process is placed in the stopped state upon
completing reception of the current frame.
Receive Control Register 2 (0x76 – 0x77): RXCR2
This register holds control information programmed by the CPU to control the receive function.
Bit Default Value R/W Description
15-5 - RO
Reserved.
4 0x0 RW
IUFFP IPV4/IPV6/UDP Fragment Frame Pass
When this bit is set, the KSZ8851M will pass the checksum check at receive side for
IPv4/IPv6 UDP frame with fragment extension header.
When this bit is cleared, the KSZ8851M will perform checksum operation based on
configuration and doesn’t care whether it’s a fragment frame or not.
3 0x0 RW
RXIUFCEZ Receive IPV4/IPV6/UDP Frame Checksum Equal Zero
When this bit is set, the KSZ8851M will pass the filtering for Ipv4/Ipv6 UDP frame with
UDP checksum equal to zero.
When this bit is cleared, the KSZ8851M will drop Ipv4/Ipv6 UDP packet with UDP
checksum equal to zero.
2 0x1 RW
UDPLFE UDP Lite Frame Enable
When this bit is set, the KSZ8851M will check the checksum at receive side and generate
the checksum at transmit side for UDP Lite frame.
When this bit is cleared, the KSZ8851M will pass the checksum check at receive side and
skip the checksum generation at transmit side for UDP Lite frame.
1 0x0 RW
RXICMPFCC Receive ICMP Frame Checksum Check Enable
When this bit is set, the KSZ8851 will check for correct ICMP checksum for incoming
ICMP frames (only for non-fragment frame). Any received ICMP frames with incorrect
checksum will be discarded.
0 0x0 RW
RXSAF Receive Source Address Filtering
When this bit is set, the KSZ8851M will drop the frame if the source address is same as
MAC address in MARL, MARM, MARH registers.
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TXQ Memory Information Register (0x78 – 0x79): TXMIR
This register indicates the amount of free memory available in the TXQ of the QMU module.
Bit Default Value R/W Description
15-13 - RO Reserved.
12-0 - RO
TXMA Transmit Memory Available
The amount of memory available is represented in units of byte. The TXQ memory is
used for both frame payload, control word.
Note: Software must be written to ensure that there is enough memory for the next
transmit frame including control information before transmit data is written to the TXQ.
0x7A – 0x7B: Reserved
Receive Frame Header Status Register (0x7C – 0x7D): RXFHSR
This register indicates the received frame header status information, the received frames are reported in RXFCTR
register. T his register contains the stat us information for the frame received and the CPU can read so many times same
as the frame count value in the RXFCTR.
Bit Default Value R/W Description
15 - RO
RXFV Receive Frame Valid
When this bit is set, it indicates that the present frame in the receive packet memory is
valid. The status information currently in this location is also valid.
When clear, it indicates that there is either no pending receive frame or that the current
frame is still in the proce ss of receiv i ng.
14 - RO
Reserved
13 - RO
RXICMPFCS Receive ICMP Frame Checksum Status
When this bit is set, the KSZ8851 received ICMP frame checksum field is incorrect.
12 - RO
RXIPFCS Receive IP Frame Checksum Status
When this bit is set, the KSZ8851 received IP header checksum field is incorrect.
11 - RO
RXTCPFCS Receive TCP Frame Checksum Status
When this bit is set, the KSZ8851 received TCP frame checksum field is incorrect.
10 - RO
RXUDPFCS Receive UDP Frame Checksum Status
When this bit is set, the KSZ8851 received UDP frame checksum field is incorrect.
9-8 - RO
Reserved
7 - RO
RXBF Receive Broadcast Frame
When this bit is set, it indicates that this frame has a broadcast address.
6 - RO
RXMF Receive Multicast Frame
When this bit is set, it indicates that this frame has a multicast address (including the
broadcast address).
5 - RO
RXUF Receive Unicast Frame
When this bit is set, it indicates that this frame has a unicast address.
4 - RO
RXMR Receive MII Error
When set, it indicates that there is an MII symbol error on the received frame.
3 - RO
RXFT Receive Frame Type
When this bit is set, it indicates that the frame is an Ethernet-type frame (frame length is
greater than 1500 bytes). When clear, it indicates that the frame is an IEEE 802.3 frame.
This bit is not valid for runt frames.
2 - RO
RXFTL Receive Frame Too Long
When this bit is set, it indicates that the frame length exceeds the maximum size of 2000
bytes. Frames that are too long are passed to the host only if the pass bad frame bit is
set.
Note: Frame too long is only a frame length indication and does not cause any frame
truncation.
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Bit Default Value R/W Description
1 - RO
RXRF Receive Runt Frame
When this bit is set, it indicates that a frame was damaged by a collision or had a
premature termination before the collision window passed.
Runt frames are passed to the host only if the pass bad frame bit is set.
0 - RO
RXCE Receive CRC Error
W hen this bit is set, it indicates that a CRC error has occurred on the current received
frame.
CRC error frames are passed to the host only if the pass bad frame bit is set.
Receive Frame Header Byte Count Register (0x7E – 0x7F): RXFHBCR
This register indicates the received frame header byte count information, the received frames are reported in RXFCTR
register. This register contains the total number of bytes information for the frame received and the CPU can read so
many times same as the frame count value in the RXFCTR.
Bit Default Value R/W Description
15-12 - RO Reserved.
11-0 - RO
RXBC Receive Byte Count
This field indicates the present received frame byte size.
TXQ Command Register (0x80 – 0x81): TXQCR
This register is programmed by the Host CPU to issue a transmit command to the TXQ. The present transmit frame in
the TXQ memory is queued for transmit.
Bit Default Value R/W Description
15-3 - RW
Reserved
2 0x0 RW
AETFE Auto-Enqueue TXQ Frame Enable
When this bit is written as 1, the KSZ8851M will enable current all TX frames prepared in
the TX buffer are queued to transmit automatically.
The bit 0 METFE has to be set 0 when this bit is set to 1 in this register.
1 0x0 RW
TXQMAM TXQ Memory Available Monitor
When this bit is written as 1, the KSZ8851M will generate interrupt (bit 6 in ISR register) to
CPU when TXQ memory is available based upon the total amount of TXQ space
requested by CPU at TXNTFSR (0x9E) register.
Note: This bit is self-clearing after the frame is finished transmitting. The software should
wait for the bit to be cleared before set to 1 again.
0 0x0 RW
METFE Manual Enqueue TXQ Frame Enable
When this bit is written as 1, the KSZ8851M will enable current TX frame prepared in the
TX buffer is queued for transmit, this is only transmit one frame at a time.
Note: This bit is self-clearing after the frame is finished transmitting. The software should
wait for the bit to be cleared before setting up another new TX frame.
RXQ Command Register (0x82 – 0x83): RXQCR
This register is programmed by the Host CPU to issue DMA read or write command to the RXQ and TXQ. This register
also is used to control all RX thresholds enable and status.
Bit Default Value R/W Description
15-13 - RW Reserved.
12 - RO
RXDTTS RX Duration Timer Threshold Status
When this bit is set, it indicates that RX interrupt is due to the time start at first received
frame in RXQ buffer exceeds the threshold set in RX Duration Timer Threshold Register
(0x8C, RXDTT).
This bit will be updated when write 1 to bit 13 in ISR register.
11 - RO
RXDBCTS RX Data Byte Count Threshold Status
When this bit is set, it indicates that RX interrupt is due to the number of received bytes in
RXQ buffer exceeds the threshold set in RX Data Byte Count Threshold Register (0x8E,
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RXDBCT).
This bit will be updated when write 1 to bit 13 in ISR register.
10 - RO
RXFCTS RX Frame Count Threshold Status
When this bit is set, it indicates that RX interrupt is due to the number of received frames
in RXQ buffer exceeds the threshold set in RX Frame Count Threshold Register (0x9C,
RXFCT).
This bit will be updated when write 1 to bit 13 in ISR register.
9 0x0 RW
RXIPHTOE RX IP Header Two-Byte Offset Enable
When this bit is written as 1, the KSZ8851M will enable to add two bytes before frame
header in order for IP header inside the frame contents to be aligned with double word
boundary to speed up software operation.
8 - RW
Reserved.
7 0x0 RW
RXDTTE RX Duration Timer Threshold Enable
When this bit is written as 1, the KSZ8851M will enable RX interrupt (bit 13 in ISR) when
the time start at first received frame in RXQ buffer exceeds the threshold set in RX
Duration Timer Threshold Register (0x8C, RXDTT).
6 0x0 RW
RXDBCTE RX Data Byte Count Threshold Enable
When this bit is written as 1, the KSZ8851M will enable RX interrupt (bit 13 in ISR) when
the number of received bytes in RXQ buffer exceeds the threshold set in RX Data Byte
Count Threshold Register (0x8E, RXDBCT).
5 0x0 RW
RXFCTE RX Frame Count Threshold Enable
When this bit is written as 1, the KSZ8851M will enable RX interrupt (bit 13 in ISR) when
the number of received frames in RXQ buffer exceeds the threshold set in RX Frame
Count Threshold Register (0x9C, RXFCT).
4 0x0 RW
ADRFE Auto-Dequeue RXQ Frame Enable
When this bit is written as 1, the KSZ8851M will automatically enable RXQ frame buffer
dequeue. The read pointer in RXQ frame buffer will be automatically adjusted to next
received frame location after current frame is completely read by the host.
3 0x0 WO
SDA Start DMA Access
When this bit is written as 1, the KSZ8851M allows a DMA operation from the host CPU
to access either read RXQ frame buffer or write TXQ frame buffer with AEN, RDN or
WRN signals regardless of the address and byte enable signals. All registers access are
disabled except this register during this DMA operation.
This bit must be set to 0 when DMA operation is finished in order to access the rest of
registers.
2-1 - RW
Reserved.
0 0x0 RW
RRXEF Release RX Error Frame
When this bit is written as 1, the current RX error frame buffer is released.
Note: This bit is self-clearing after the frame memory is released. The software should
wait for the bit to be cleared before processing new RX frame.
TX Frame Data Pointer Register (0x84 – 0x85): TXFDPR
The val ue of this re gis ter d etermines the addr ess t o be acc ess ed with in the T X Q fram e buff er . When the AUT O incr em ent
is set, It will automatically increment the pointer value on write accesses to the data register.
The counter is incremented by one for every byte access, by two for every word access, and by four for every double
word access.
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Bit Default Value R/W Description
15 - RO
Reserved.
14 0x0 RW
TXFPAI TX Frame Data Pointer Auto Increment
When this bit is set, the TX Frame data pointer register increments automatically on
accesses to the data register. The increment is by one for every byte access, by two for
every word access, and by four for every doubleword access.
When this bit is reset, the TX frame data pointer is manually controlled by user to access
the TX frame location.
13-11 - RO Reserved.
10-0 0x000 RO
TXFP TX Frame Pointer
TX Frame Pointer index to the Frame Data register for access.
This field reset to next available TX frame location when the TX Frame Data has been
enqueued through the TXQ command register.
RX Frame Data Pointer Register (0x86 – 0x87): RXFDPR
The valu e of this register determines the address to be ac cessed within the RXQ fram e buffer. W hen the Auto Increm ent
is set, it will automatically increment the RXQ Pointer on read accesses to the data register.
The counter is incremented is by one for every byte access, by two for every word access, and by four for every double
word access.
Bit Default Value R/W Description
15 - RO
Reserved.
14 0x0 RW
RXFPAI RX Frame Pointer Auto Increment
When this bit is set, the RXQ Address register increments automatically on accesses to
the data register. The increment is by one for every byte access, by two for every word
access, and by four for every double word access.
When this bit is reset, the RX frame data pointer is manually controlled by user to access
the RX frame location.
13 - RO
Reserved.
12 0x0 RW
WST Write Sample Time
This bit is used to select the WRN active to write data valid time as shown in Figure 12.
0: WRN active to write data valid sample time is range of 8nS(min) to 16nS(max).
1: WRN active to write data valid sample time is 4nS(max).
11 0x0 WO
(Read
back
is “0”)
EMS Endian Mode Selection
This bit is used to select either Big or Little Endian mode when Endian mode select
strapping pin (29) is NC or tied to GND.
0: is set to Little Endian Mode
1: is set to Big Endian Mode
10-0 0x000 WO
RXFP RX Frame Pointer
RX Frame data pointer index to the Data register for access.
This pointer value must reset to 0x000 before each DMA operation from the host CPU to
read RXQ frame buffer.
0x88 – 0x8B: Reserved
RX Duration Timer Threshold Register (0x8C – 0x8D): RXDTTR
This register is used to program the received frame duration timer threshold.
Bit Default Value R/W Description
15-0 0x0000 RW
RXDTT Receive Duration Timer Threshold
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To program received frame duration timer threshold value in 1us interval. The maximum
value is 0xCFFF.
When bit 7 set to 1 in RXQCR register, the KSZ8851M will set RX interrupt (bit 13 in ISR)
after the time starts at first received frame in RXQ buffer and exceeds the threshold set in
this register.
RX Data Byte Count Threshold Register (0x8E – 0x8F): RXDBCTR
This register is used to program the received data byte count threshold.
Bit Default Value R/W Description
15-0 0x0000 RW
RXDBCT Receive Data Byte Count Threshold
To program received data byte threshold value in byte count.
When bit 6 set to 1 in RXQCR register, the KSZ8851M will set RX interrupt (bit 13 in ISR)
when the number of received bytes in RXQ buffer exceeds the threshold set in this
register.
Interrupt Enable Register (0x90 – 0x91): IER
This register enables the interrupts from the QMU and other sources.
Bit Default Value R/W Description
15 0x0 RW
LCIE Link Change Interrupt Enable
When this bit is set, the link change interrupt is enabled.
When this bit is reset, the link change interrupt is disabled.
14 0x0 RW
TXIE Transmit Interrupt Enable
When this bit is set, the transmit interrupt is enabled.
When this bit is reset, the transmit interrupt is disabled.
13 0x0 RW
RXIE Receive Interrupt Enable
When this bit is set, the receive interrupt is enabled.
When this bit is reset, the receive interrupt is disabled.
12 0x0 RW
Reserved
11 0x0 RW
RXOIE Receive Overrun Interrupt Enable
When this bit is set, the Receive Overrun interrupt is enabled.
When this bit is reset, the Receive Overrun interrupt is disabled.
10 0x0 RW
Reserved
9 0x0 RW
TXPSIE Transmit Process Stopped Interrupt Enable
When this bit is set, the Transmit Process Stopped interrupt is enabled.
When this bit is reset, the Transmit Process Stopped interrupt is disabled.
8 0x0 RW
RXPSIE Receive Process Stopped Interrupt Enable
When this bit is set, the Receive Process Stopped interrupt is enabled.
When this bit is reset, the Receive Process Stopped interrupt is disabled.
7 0x0 RW
Reserved
6 0x0 RW
TXSAIE Transmit Space Available Interrupt Enable
When this bit is set, the Transmit memory space available interrupt is enabled.
When this bit is reset, the Transmit memory space available interrupt is disabled.
5 0x0 RW
RXWFDIE Receive Wake-up Frame Detect Interrupt Enable
When this bit is set, the Receive wakeup frame detect interrupt is enabled.
When this bit is reset, the Receive wakeup frame detect interrupt is disabled.
4 0x0 RW
RXMPDIE Receive Magic Packet Detect Interrupt Enable
When this bit is set, the Receive magic packet detect interrupt is enabled.
When this bit is reset, the Receive magic packet detect interrupt is disabled.
3 0x0 RW
LDIE Linkup Detect Interrupt Enable
When this bit is set, the wake-up from linkup detect interrupt is enabled.
When this bit is reset, the linkup detect interrupt is disabled.
2 0x0 RW
EDIE Energy Detect Interrupt Enable
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Bit Default Value R/W Description
When this bit is set, the wake-up from energy detect interrupt is enabled.
When this bit is reset, the energy detect interrupt is disabled.
1 0x0 RO
Reserved
0 0x0 RW
DEDIE Delay Energy Detect Interrupt Enable
When this bit is set, the delay energy detect interrupt is enabled.
When this bit is reset, the delay energy detect interrupt is disabled.
Note: the delay energy detect interrupt till device is ready for host access.
Interrupt Status Register (0x92 – 0x93): ISR
This register contains the status bits for all QMU and other interrupt sources.
When the corresponding enable bit is set, it causes the interrupt pin to be asserted.
This register is usually read by the host CPU and device drivers during interrupt service routine or polling. The register
bits are not cleared when read. The user has to write “1” to clear.
Bit Default Value R/W Description
15 0x0 RO
(W1C) LCIS Link Change Interrupt Status
When this bit is set, it indicates that the link status has changed from link up to link down,
or link down to link up.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
14 0x0 RO
(W1C) TXIS Transmit Interrupt Status
When this bit is set, it indicates that the TXQ MAC has transmitted at least a frame on the
MAC interface and the QMU TXQ is ready for new frames from the host.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
13 0x0 RO
(W1C) RXIS Receive Interrupt Status
When this bit is set, it indicates that the QMU RXQ has received at least a frame from the
MAC interface and the frame is ready for the host CPU to process.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
12 0x0 RO
Reserved
11 0x0 RO
(W1C) RXOIS Receive Overrun Interrupt Status
When this bit is set, it indicates that the Receive Overrun status has occurred.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
10 0x0 RO
Reserved
9 0x1 RO
(W1C) TXPSIS Transmit Process Stopped Interrupt Status
When this bit is set, it indicates that the Transmit Process has stopped.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
8 0x1 RO
(W1C) RXPSIS Receive Process Stopped Interrupt Status
When this bit is set, it indicates that the Receive Process has stopped.
This edge-triggered interrupt status is cleared by writing 1 to this bit.
7 0x0 RO
Reserved
6 0x0 RO
(W1C) TXSAIS Transmit Space Available Interrupt Status
When this bit is set, it indicates that Transmit memory space available status has
occurred.
When this bit is reset, the Transmit memory space available interrupt is disabled.
5 0x0 RO
RXWFDIS Receive Wakeup Frame Detect Interrupt Status
When this bit is set, it indicates that Receive wakeup frame detect status has occurred.
Write “1000” to PMECR[5:2] to clear this bit
4 0x0 RO
RXMPDIS Receive Magic Packet Detect Interrupt Status
When this bit is set, it indicates that Receive magic packet detect status has occurred.
Write “0100” to PMECR[5:2] to clear this bit.
3 0x0 RO
LDIS Linkup Detect Interrupt Status
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Bit Default Value R/W Description
When this bit is set, it indicates that wake-up from linkup detect status has occurred.
Write “0010” to PMECR[5:2] to clear this bit.
2 0x0 RO
EDIS Energy Detect Interrupt Status
When this bit is set and bit 2=1, bit 0=0 in IER register, it indicates that wake-up from
energy detect status has occurred. When this bit is set and bit 2, 0=1 in IER register, it
indicates that wake-up from delay energy detect status has occurred.
Write “0001” to PMECR[5:2] to clear this bit.
1 0x0 RO
Reserved
0 0x0 RO
Reserved
0x94 – 0x9B: Reserved
RX Frame Count & Threshold Register (0x9C – 0x9D): RXFCTR
This register indicat es the curr ent total amount of received fr ame count in RXQ fram e buffer and also is us ed to program
the received frame count threshold.
Bit Default Value R/W Description
15-8 0x00 RO
RXFC RX Frame Count
To indicate the total received frames in RXQ frame buffer when receive interrupt (bit13=1
in ISR) occurred and write “1” to clear this bit 13 in ISR. The host CPU can start to read
the updated receive frame header information in RXFHSR/RXFHBCR registers after read
this RX frame count register.
7-0 0x00 RW
RXFCT Receive Frame Count Threshold
To program received frame count threshold value.
When bit 5 set to 1 in RXQCR register, the KSZ8851M will set RX interrupt (bit 13 in ISR)
when the number of received frames in RXQ buffer exceeds the threshold set in this
register.
TX Next Total Frames Size Register (0x9E – 0x9F): TXNTFSR
This register is used by the host CPU to program the total amount of TXQ buffer space requested for the next transmit.
Bit Default Value R/W Description
15-0 0x0000 RW
TXNTFS TX Next Total Fram es Size
The host CPU is used to program the total amount of TXQ buffer space which is required
for next total transmit frames size in double-word count.
When bit 1 (TXQ memory available monitor) is set to 1 in TXQCR register, the KSZ8851M
will generate interrupt (bit 6 in ISR register) to CPU when TXQ memory is available based
upon the total amount of TXQ space requested by CPU at this register.
MAC Address Hash Table Register 0 (0xA0 – 0xA1): MAHTR0
The 64-bit MAC addr ess table is us e d f or group addr e s s f ilterin g and it is ena bl ed b y select ing item 5 “ Has h perf ect ” m ode
in Table 3 (Address Filtering Scheme).
This value is def ined as the s ix mos t significant b its fr om CRC c ircuit calc ulatio n result th at is base d on 48- bit of DA input .
The two most significant bits select one of the four registers to be used, while the others determine which bit within the
register.
Multicast table register 0.
Bit Default Value R/W Description
15-0 0x0 RW
HT0 Hash Table 0
W hen the appropriate bit is set, if the packet received with DA matches the CRC, the
hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
MAC Address Hash Table Register 1 (0xA2 – 0xA3): MAHTR1
Multicast table register 1.
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Bit Default Value R/W Description
15-0 0x0 RW
HT1 Hash Table 1
W hen the appropriate bit is set, if the packet received with DA matches the CRC, the
hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXAE) or receive multicast (RXME) bit is set in the RXCR1,
all multicast addresses are received regardless of the multicast table value.
MAC Address Hash Table Register 2 (0xA4 – 0xA5): MAHTR2
Multicast table register 2.
Bit Default Value R/W Description
15-0 0x0 RW
HT2 Hash Table 2
W hen the appropriate bit is set, if the packet received with DA matches the CRC, the
hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXAE) or receive multicast (RXME) bit is set in the RXCR1,
all multicast addresses are received regardless of the multicast table value.
MAC Address Hash Table Register 3 (0xA6 – 0xA7): MAHTR3
Multicast table register 3.
Bit Default Value R/W Description
15-0 0x0 RW
HT3 Hash Table 3
W hen the appropriate bit is set, if the packet received with DA matches the CRC, the
hashing function is received without being filtered.
When the appropriate bit is cleared, the packet will drop.
Note: When the receive all (RXAE) or receive multicast (RXME) bit is set in the RXCR1,
all multicast addresses are received regardless of the multicast table value.
0xA8 – 0xAF: Reserved
Flow Control Low Watermark Register (0xB0 – 0xB1): FCLWR
This register is used to control the flow control for low watermark in QMU RX queue.
Bit Default Value R/W Description
15-12 - RW Reserved
11-0 0x0500 RW
FCLWC Flow Control Low Watermark Configuration
These bits are used to define the QMU RX queue low watermark configuration. It is in
double words count and default is 5.12 KByte available buffer space out of 12 KByte.
Flow Control High Watermark Register (0xB2 – 0xB3): FCHWR
This register is used to control the flow control for high watermark in QMU RX queue.
Bit Default Value R/W Description
15-12 - RW Reserved
11-0 0x0300 RW
FCHWC Flow Control High Watermark Configuration
These bits are used to define the QMU RX queue high watermark configuration. It is in
double words count and default is 3.072 KByte available buffer space out of 12 KByte.
Flow Control Overrun Watermark Register (0xB4 – 0xB5): FCOWR
This register is used to control the flow control for overrun watermark in QMU RX queue
Bit Default Value R/W Description
15-12 - RW Reserved
11-0 0x0040 RW
FCLWC Flow Control Overrun Watermark Configuration
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These bits are used to define the QMU RX queue overrun watermark configuration. It is in
double words count and default is 256 Bytes available buffer space out of 12 Kbyte.
0xB6 – 0xBF: Reserved
Chip ID and Enable Register (0xC0 – 0xC1): CIDER
This register contains the chip ID and the chip enable bit.
Bit Default R/W Description
15-8 0x88 RO
Family ID
Chip family ID
7-4 0x7 RO
Chip ID
0x7 is assigned to KSZ8851-16/32MQL
3-1 0x1 RO
Revision ID
0 0x0 RW
Reserved
0xC2 – 0xC5: Reserved
Chip Global Control Register (0xC6 – 0xC7): CGCR
This register contains the global control for the chip function.
Bit Default R/W Description
15 0x0 RW LEDSEL1
See description for bit 9.
14-12 0x0 RW Reserved.
11-10 0x2 RW Reserved.
9 0x0 RW LEDSEL0
This bit sets the LEDSEL0 selection and bit 15 sets the LEDSEL1 selection.
PHY port LED indicators, defined as below:
[LEDSEL1 (bit15), LEDSEL0 (bit9)]
[0, 0] [0, 1]
P1LED3 ------ ------
P1LED2 LINK/ACT 100LINK/ACT
P1LED1 FULL_DPX/COL 10LINK/ACT
P1LED0 SPEED FULL_DPX
[LEDSEL1, LEDSEL0]
[1, 0] [1, 1]
P1LED3 ACT NA
P1LED2 LINK NA
P1LED1 FULL_DPX/COL NA
P1LED0 SPEED NA
8 0x0 R/W
Reserved.
7-0 0x35 RW Reserved.
Indirect Access Control Register (0xC8 – 0xC9): IACR
This register contains the indirect control for the MIB counter (Write IACR triggers a command. Read access is
determ ined b y bit 12).
Bit Default R/W Description
15-13 0x0 RW Reserved.
12 0x0 RW Read Enable.
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1 = Read cycle is enabled (MIB counter will clear after read).
0 = No operation.
11-10 0x0 RW Table Select
00 = reserved.
01 = reserved.
10 = reserved.
11 = MIB counter selected.
9-5 - RW Reserved.
4-0 0x00 RW Indirect Address
Bit 4-0 of indirect address for 32 MIB counter locations.
0xCA – 0xCF: Reserved
Indirect Access Data Low Register (0xD0 – 0xD1): IADLR
This register contains the indirect data (low word) for MIB counter.
Bit Default R/W Description
15-0 0x0000 RW Indirect Low Word Data
Bit 15-0 of indirect data.
Indirect Access Data High Register (0xD2 – 0xD3): IADHR
This register contains the indirect data (high word) for MIB counter.
Bit Default R/W Description
15-0 0x0000 RW Indirect High Word Data
Bit 31-16 of indirect data.
Power Management Event Control Register (0xD4 – 0xD5): PMECR
This register is used to control the KSZ8851M power management event, capabilities and status.
Bit Default R/W Description
15 - RO Reserved.
14 0 RW PME Delay Enable
This bit is used to enable the delay of PME output pin assertion.
When this bit is set to 1, the device will not assert the PME output till the device’s all
clocks are running and ready for host access.
When this bit is set to 0, the device will assert the PME output without delay.
This bit is only valid when Auto Wake-Up Enable (bit7) is set to 1 in this register.
13 0 RW Reserved
12 0 RW PME Output Polarity
This bit is used to control the PME output pin polarity.
When this bit is set to 1, the PME output pin is active high.
When this bit is set to 0, the PME output pin is active low.
11-8 0x0 RW Wake-on-LAN to PME Output Enable
These four bits are used to enable the PME output pin asserted when one of these wake-
on-LAN events is detected:
Bit 11: is corresponding to receive wake-up frame.
Bit 10: is corresponding to receive magic packet.
Bit 9: is corresponding to link change from down to up.
Bit 8: is corresponding to signal energy detected.
When the bit is set to 1, the PME pin will be asserted when a corresponding wake-on-
LAN event is occurred.
When this bit is set to 0, the PME pin will be not asserted when a corresponding wake-
on-LAN event is occurred.
7 0 RW Auto Wake-Up Enable
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Bit Default R/W Description
This bit is used to enable automatically wake-up from low power state to normal power
state in energy detect mode if carrier (signal energy) is present more than wake-up time in
GSWUTR register. During the normal power state, the device can receive and transmit
packets.
When this bit is set to 1, the auto wake-up is enabled in energy detect mode.
When this bit is set to 0, the auto wake-up is disabled in energy detect mode.
6 0 RW Wake-Up to Normal Operation Mode
This bit is used to control the device wake-up from low power state in energy detect mode
to normal operation mode if signal energy is detected longer than the programmed wake-
up time in GSWUTR register.
When this bit is set to 1, the device will automatically go to the normal operation mode
from energy detect mode.
When this bit is set to 0, the device will not automatically go to the normal mode from
energy detect mode.
This bit is only valid when Auto Wake-Up Enable (bit7) is set to 1.
5-2 0x0 RO
(W1C) Wake-Up Event Indication
These four bits are used to indicate the KSZ8851M wake-up event status as below:
0000: No wake-up event.
0001: Wake-up from energy event detected. (Bit 2 also set to 1 in ISR register)
0010: Wake-up from link up event detected. (Bit 3 also set to 1 in ISR register)
0100: Wake-up from magic packet event detected.
1000: Wake-up from wakeup frame event detected.
If Wake-on-LAN to PME Output Enable bit[11:8] are set, the KSZ8851M also asserts the
PME pin. These bits are cleared on power up reset or by write 1. It is not modified by
either hardware or software reset. When these bits are cleared, the KSZ8851M deasserts
the PME pin.
1-0 0x0 RW Power Management Mode
These two bits are used to control the KSZ8851M power management mode as below:
00: Normal Operation Mode.
01: Energy Detect Mode. (two states in this mode either low power or normal power)
10: Soft Power Down Mode.
11: Power Saving Mode.
In energy detect mode under low power state, it can wake-up to normal operation mode
either from line or host wake-up (host CPU issues a read cycle to GRR register).
In soft power down mode, it can wake-up to normal operation mode only from host wake-
up (host CPU issues a read cycle to GRR register).
Go-Sleep & Wake-Up Time Register (0xD6 – 0xD7): GSWUTR
This register contains the value which is used to control minimum Go-Sleep time period when the device from normal
power state to low power state or to control minimum Wake-Up time period when the device from low power state to
normal power state in energy detect mode.
Bit Default R/W Description
15-8 0x08 RW Wake-up Time
This value is used to control the minimum period that the energy has to be detected
consecutively before the device is waked-up from the low power state. The unit is 16 ms +/-
80%, the default wake-up time is 128 ms (16ms x 8). Zero time (0x00) is not allowed.
7-0 0x0C RW Go-sleep Time
This value is used to control the minimum period that the no energy event has to be
detected consecutively before the device enters the low power state when the energy detect
mode is on. The unit is 1 sec +/-80%, the default go-sleep time is 12 sec (1s x 12). Zero
time (0x00) is not allowed.
PHY Reset Register (0xD8 – 0xD9): PHYRR
This register contains a control bit to reset PHY block when write an “1”.
Bit Default R/W Description
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15-1 - RW Reserved.
0 0 WO
(Self clear) PHY Reset Bit
This bit is write only and self clear after write an “1”, it is used to reset PHY block circuitry.
0xDA – 0xDF: Reserved
0xE0 – 0xE3: Reserved
PHY 1 MII-Register Basic Control Register (0xE4 – 0xE5): P1MBCR
This register contains Media Independent Interface (MII) register for port 1 as defined in the IEEE 802.3 specification.
Bit Default R/W Description Bit is same as:
15 0 RO Reserved
14 0 RW Local (far-end) loopback (llb)
1 = perform local loopback at host
(host Tx -> PHY -> host Rx, see Figure 11)
0 = normal operation
13 1 RW Force 100
1 = force 100Mbps if AN is disabled (bit 12)
0 = force 10Mbps if AN is disabled (bit 12)
Bit 6 in P1CR
12 1 RW AN Enable
1 = auto-negotiation enabled.
0 = auto-negotiation disabled.
Bit 7 in P1CR
11-10 0 RW Reserved
9 0 RW Restart AN
1 = restart auto-negotiation.
0 = normal operation.
Bit 13 in P1CR
8 1 RW Force Full Duplex
1 = force full duplex
0 = force half duplex.
if AN is disabled (bit 12) or AN is enabled but failed.
Bit 5 in P1CR
7-6 0 RO Reserved
5 1 R/W HP_mdix
1 = HP Auto MDI-X mode.
0 = Micrel Auto MDI-X mode.
Bit 15 in P1SR
4 0 RW Force MDI-X
1 = force MDI-X.
0 = normal operation.
Bit 9 in P1CR
3 0 RW Disable MDI-X
1 = disable auto MDI-X.
0 = normal operation.
Bit 10 in P1CR
2 0 RW Reserved.
1 0 RW Disable Transmit
1 = disable transmit.
0 = normal operation.
Bit 14 in P1CR
0 0 RW Disable LED
1 = disable all LEDs.
0 = normal operation.
Bit 15 in P1CR
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PHY 1 MII-Register Basic Status Register (0xE6 – 0xE7): P1MBSR
This register contains the MII register status for the chip function.
Bit Default R/W Description Bit is same as:
15 0 RO T4 Capable
1 = 100 BASE-T4 capable.
0 = not 100 BASE-T4 capable.
14 1 RO 100 Full Capable
1 = 100BASE-TX full-duplex capable.
0 = not 100BASE-TX full duplex.capable.
13 1 RO 100 Half Capable
1= 100BASE-TX half-duplex capable.
0= not 100BASE-TX half-duplex capable.
12 1 RO 10 Full Capable
1 = 10BASE-T full-duplex capable.
0 = not 10BASE-T full-duplex capable.
11 1 RO 10 Half Capable
1 = 10BASE-T half-duplex capable.
0 = not 10BASE-T half-duplex capable.
10-7 0x0 RO Reserved.
6 0 RO Preamble suppre ssed
Not supported.
5 0 RO AN Complete
1 = auto-negotiation complete.
0 = auto-negotiation not completed.
Bit 6 in P1SR
4 0 RO Reserved
3 1 RO AN Capable
1 = auto-negotiation capable.
0 = not auto-negotiation capable.
2 0 RO Link Status
1 = link is up.
0 = link is down.
Bit 5 in P1SR
1 0 RO Jabber Test
Not supported.
0 0 RO Extended Capable
1 = extended register capable.
0 = not extended register capable.
PHY 1 PHY ID Low Register (0xE8 – 0xE9): PHY1ILR
This register contains the PHY ID (low) for the chip.
Bit Default R/W Description
15-0 0x1430 RO PHYID Low
Low order PHYID bits.
PHY 1 PHY ID High Register (0xEA – 0xEB): PHY1IHR
This register contains the PHY ID (high) for the chip.
Bit Default R/W Description
15-0 0x0022 RO PHYID High
High order PHYID bits.
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PHY 1 Auto-Negotiation Advertisement Register (0xEC – 0xED): P1ANAR
This register contains the auto-negotiation advertisement for the PHY function.
Bit Default R/W Description Bit is same as:
15 0 RO Next page
Not supported.
14 0 RO Reserved
13 0 RO Remote fault
Not supported.
12-11 0x0 RO Reserved
10 1 RW Pause (flow control capability)
1 = advertise pause capability.
0 = do not advertise pause capability.
Bit 4 in P1CR
9 0 RW
Reserved.
8 1 RW
Adv 100 Full
1 = advertise 100 full-duplex capability.
0 = do not advertise 100 full-duplex capability
Bit 3 in P1CR
7 1 RW
Adv 100 Half
1= advertise 100 half-dup lex capability.
0 = do not advertise 100 half-duplex capability.
Bit 2 in P1CR
6 1 RW
Adv 10 Full
1 = advertise 10 full-duplex capability.
0 = do not advertise 10 full-duplex capability.
Bit 1 in P1CR
5 1 RW
Adv 10 Half
1 = advertise 10 half-duplex capability.
0 = do not advertise 10 half-duplex capability.
Bit 0 in P1CR
4-0 0x01 RO Selector Field
802.3
PHY 1 Auto-Negotiation Link Partner Ability Register (0xEE – 0xEF): P1ANLPR
This register contains the auto-negotiation link partner ability for the chip function.
Bit Default R/W Description Bit is same as:
15 0 RO Next page
Not supported.
14 0 RO LP ACK
Not supported.
13 0 RO Remote fault
Not supported.
12-11 0x0 RO Reserved
10 0 RO Pause
Link partner pause capability. Bit 4 in P1SR
9 0 RO
Reserved.
8 0 RO
Adv 100 Full
Link partner 100 full capability. Bit 3 in P1SR
7 0 RO
Adv 100 Half
Link partner 100 half capability. Bit 2 in P1SR
6 0 RO
Adv 10 Full
Link partner 10 full capability. Bit 1 in P1SR
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Bit Default R/W Description Bit is same as:
5 0 RO
Adv 10 Half
Link partner 10 half capability. Bit 0 in P1SR
4-0 0x01 RO Reserved.
0xF0 – 0xF3: Reserved
Port 1 PHY Special Control/Status, LinkMD® (0xF4 – 0xF5): P1SCLMD
This register contains the special control, status and LinkMD® information of PHY1.
Bit Default R/W Description Bit is same as:
15 0 RO Reserved
14-13 0x0 RO Vct_result
VCT result.
[00] = normal conditi on.
[01] = open condition has been detected in cable.
[10] = short condition has been detected in cable.
[11] = cable diagnostic test is failed.
12 0 RW
(Self-Clear) Vct_en
Vct enable.
1 = the cable diagnostic test is enabled. It is self-
cleared after the VCT test is done.
0 = it indicates the cable diagn ostic test is completed
and the status information is valid for read.
11 0 RW Force_lnk
Force link.
1 = force link pass.
0 = normal operation.
10 0 RO Reserved
9 0 RW Remote (Near-end) loopback (rlb)
1 = perform remote loopback at PHY
(RXP1/RXM1 -> TXP1/TXM1, see Figure 11)
0 = normal operation
8-0 0x000 RO Vct_fault_count
VCT fault count.
Distance to the fault. It’s approximately
0.4m*vct_fault_count.
Port 1 Control Register (0xF6 – 0xF7): P1CR
This register contains the global per port control for the chip function.
Bit Default R/W Description Bit is same as:
15 0 RW LED Off
1 = Turn off all of the port 1 LEDs (P1LED3, P1LED2,
P1LED1, P1LED0). These pins are driven high if this bit
is set to one.
0 = normal operation.
Bit 0 in P1MBCR
14 0 RW Txids
1 = disable the port’s transmitter.
0 = normal operation.
Bit 1 in P1MBCR
13 0 RW Restart AN Bit 9 in P1MBCR
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Bit Default R/W Description Bit is same as:
1 = restart auto-negotiation.
0 = normal operation.
12 0 RW Reserved
11 0 RW Reserved
10 0 RW Disable auto MD I/MDI-X
1 = disable auto MDI/MDI-X function.
0 = enable auto MDI/MDI-X function.
Bit 3 in P1MBCR
9 0 RW Force MDI-X
1= if auto MDI/MDI-X is disabled, force PHY into MDI-X
mode.
0 = do not force PHY into MDI-X mode.
Bit 4 in P1MBCR
8 0 RW Reserved
7 1 RW Auto Negotiation Enable
1 = auto negotiation is enabled.
0 = disable auto negotiation , speed, and dup lex are
decided by bits 6 and 5 of the same register.
Bit 12 in P1MBCR
6 1 RW Force Speed
1 = force 100BT if AN is disabled (bit 7).
0 = force 10BT if AN is disabled (bit 7).
Bit 13 in P1MBCR
5 1
RW Force Duplex
1 = force full duplex if (1) AN is disabled or (2) AN is
enabled but failed.
0 = force half duplex if (1) AN is disabled or (2) AN is
enabled but failed.
Bit 8 in P1MBCR
4 1 RW Advertised flow control capability.
1 = advertise flow control (pause) capability.
0 = suppress flow control (pause) capability from
transmission to link partner.
Bit 10 in P1ANAR
3 1 RW Advertised 100BT full-duplex capability.
1 = advertise 100BT full-duplex capability.
0 = suppress 100BT full-duplex capability from
transmission to link partner.
Bit 8 in P1ANAR
2 1 RW Advertised 100BT half-duplex capability.
1 = advertise 100BT half-duplex capability.
0 = suppress 100BT half-duplex capability from
transmission to link partner.
Bit 7 in P1ANAR
1 1 RW Advertised 10BT full-duplex capability.
1 = advertise 10BT full-duplex capability.
0 = suppress 10BT full-duplex capability from
transmission to link partner.
Bit 6 in P1ANAR
0 1 RW Advertised 10BT half-duplex capability.
1 = advertise 10BT half-duplex capability.
0 = suppress 10BT half-duplex capability from
transmission to link partner.
Bit 5 in P1ANAR
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Port 1 Status Register (0xF8 – 0xF9): P1SR
This register contains the PHY port status for the chip function.
Bit Default R/W Description Bit is same as:
15 1 RW HP_mdix
1 = HP Auto MDI-X mode.
0 = Micrel Auto MDI-X mode.
Bit 5 in P1MBCR
14 0 RO Reserved
13 0 RO Polarity Reverse
1 = polarity is reversed.
0 = polarity is not reversed.
12-11 0 RO Reserved
10 0 RO Operation Speed
1 = link speed is 100Mbps.
0 = link speed is 10Mbps.
9 0 RO Operation Duplex
1 = link duplex is full.
0 = link duplex is half.
8 0 RO Reserved
7 1 RO MDI-X status
1 = MDI.
0 = MDI-X.
6 0 RO AN Done
1 = AN done.
0 = AN not done.
Bit 5 in P1MBSR
5 0 RO Link Good
1= link good.
0 = link not good.
Bit 2 in P1MBSR
4 0 RO Partner flow control capability.
1 = link partner flow control (pause) capable.
0 = link partner not flow control (pause) capable.
Bit 10 in P1ANLPR
3 0 RO Partner 100BT full-duplex capability.
1 = link partner 100BT full-duplex capable.
0 = link partner not 100BT full-duplex capable.
Bit 8 in P1ANLPR
2 0 RO Partner 100BT half-duplex capability.
1 = link partner 100BT half-duplex capable.
0= link partner not 100BT half-duplex capable.
Bit 7 in P1ANLPR
1 0 RO Partner 10BT full-duplex capability.
1= link partner 10BT full-duplex capable.
0 = link partner not 10BT full-duplex capable.
Bit 6 in P1ANLPR
0 0 RO Partner 10BT half-duplex capability.
1 = link partner 10BT half-duplex capable.
0 = link partner not 10BT half-duplex capable.
Bit 5 in P1ANLPR
0xFA – 0xFF: Reserved
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MIB (Management Information Base) Counters
The KSZ8851M provides 32 MIB counters to monitor the port activity for network management. The MIB counters are
formatted as shown below:
Bit Name R/W Description Default
31-0 Counter values RO Counter value (read clear) 0x00000000
Table 13. Format of MIB Counters
Ethernet port MIB counters are read using indirect memory access. The address offset range is 0x00 to 0x1F.
Offset Counter Name Description
0x0 RxByte Rx octet count including bad packets
0x1 Reserved Reserved.
0x2 RxUndersizePkt Rx undersize packets w/ good CRC
0x3 RxFragments Rx fragment packets w/ bad CRC, symbol errors or alignment errors
0x4 RxOversize Rx oversize packets w/ good CRC (max: 1536 bytes)
0x5 RxJabbers Rx packets longer than 1536 bytes w/ either CRC errors, alignment errors, or symbol errors
0x6 RxSymbolError Rx packets w/ invalid data symbol and legal packet size.
0x7 RxCRCError Rx packets within (64,2000) bytes w/ an integral number of bytes and a bad CRC
0x8 RxAlignmentError Rx packets within (64,2000) bytes w/ a non-integral number of bytes and a bad CRC
0x9 RxControl8808Pkts Number of MAC control frames received by a port with 88-08h in EtherType field
0xA RxPausePkts Number of PAUSE frames received by a port. PAUSE frame is qualified with EtherType (88-
08h), DA, control opcode (00-01), data length (64B min), and a valid CRC
0xB RxBroadcast Rx good broadcast packets (not including error broadcast packets or valid multicast packets)
0xC RxMulticast Rx good multicast packets (not including MAC control frames, error multicast packets or valid
broadcast packets)
0xD RxUnicast Rx good unicast packets
0xE Rx64Octets Total Rx packets (bad packets included) that were 64 octets in length
0xF Rx65to127Octets Total Rx packets (bad packets included) that are between 65 and 127 octets in length
0x10 Rx128to255Octets Total Rx packets (bad packets included) that are between 128 and 255 octets in length
0x11 Rx256to511Octets Total Rx packets (bad packets included) that are between 256 and 511 octets in length
0x12 Rx512to1023Octets Total Rx packets (bad packets included) that are between 512 and 1023 octets in length
0x13 Rx1024to1521Octets Total Rx packets (bad packets included) that are between 1024 and 1521 octets in length
0x14 Rx1522to2000Octets Total Rx packets (bad packets included) that are between 1522 and 2000 octets in length
0x15 TxByte Tx good octet count, including PAUSE packets
0x16 TxLateCollision The number of times a collision is detected later than 512 bit-times into the Tx of a packet
0x17 TxPausePkts Number of PAUSE frames transmitted by a port
0x18 TxBroadcastPkts Tx good broadcast packets (not including error broadcast or valid multica st packet s)
0x19 TxMulticastPkts Tx good multicast packets (not including error multicast packets or valid broadcast packets)
0x1A TxUnicastPkts Tx good unicast packets
0x1B TxDeferred Tx packets by a port for which the 1st Tx attempt is delayed due to the busy medium
0x1C TxTotalCollision Tx total collision, half duplex only
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Offset Counter Name Description
0x1D TxExcessiveCollision A count of frames for which Tx fails due to excessive collisions
0x1E TxSingleCollision Successfully Tx frames on a port for which Tx is inhibited by exactly one collision
0x1F TxMultipleCollision Successfully Tx frames on a port for which Tx is inhibited by more than one collision
Table 14. Port 1 MIB Counters Indirect Memory Offsets
Example:
1. MIB Counter Read (read port 1 “Rx64Octets” counter at indirect address offset 0x0E)
Write to reg. IACR (0xC8) with 0x1C0E (set indirect address and trigger a read MIB counters operation)
Then
Read reg. IADHR (MIB counter value 31-16)
Read reg. IADLR (MIB counter value 15-0)
A dditional MIB Information
In the heaviest c ondition, t he byte counter will overflo w in 2 minutes. It is rec omm ended that the softwar e read all
the counters at least every 30 seconds.
MIB counters are designed as “read clear”. That is, these counters will be cleared after they are read.
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Absolute Maximum Ratings(1)
Supply Voltage (VDDATX, VDDARX, VDDIO) ... 0.5V to +4.0V
Input Voltage (All Inputs)..............................–0.5V to +4.0V
Output Voltage (All Outputs)........................ –0.5V to +4.0V
Lead Temperature (soldering, 20sec.).......................260°C
Storage Temperature (Ts).........................–65°C to +150°C
Maximum Junction Temperature (TJ).......................+125°C
HBM ESD Rating .......................................................... 6K V
Operating Ratings(2)
Suppl y Voltag e
VDDATX, VDDARX............................+3.1V to +3.5V
VDDIO (3.3V) .....................................+3.1V to +3.5V
VDDIO (2.5V) .................................+2.35V to +2.65V
VDDIO (1.8V) .....................................+1.7V to +1.9V
Ambient Operating Temperature (TA)
Commercial (MQL)…………….…………......0°C to +70°C
Industrial (MQLI)……………….…………...-40°C to +85°C
Thermal Resistance(3)
Junction-to-Ambient (θJA)....................42.91°C/W
Junction-to-Case (θJC)...........................19.6°C/W
Electrical Characteristics(4, 5)
Symbol Parameter Condition Min Typ Max Units
Supply Current for 100BASE-TX Operation (Single Port@100% Utilization)
VDDATX, VDDARX, VDDIO = 3.3V;
Chip only (no transformer) 85 mA
VDDATX/VDDARX = 3.3V, VDDIO = 2.5V;
Chip only (no transformer) 85 mA
Idd1 100BASE-TX
(analog core + PLL + digital
core + transceiver + digital I/O)
VDDATX/VDDARX = 3.3V, VDDIO = 1.8V;
Chip only (no transformer) 85 mA
Supply Current for 10BASE-T Operation (Single Port@100% Utilization)
VDDATX, VDDARX, VDDIO = 3.3V;
Chip only (no transformer) 75 mA
VDDATX/VDDARX = 3.3V, VDDIO = 2.5V;
Chip only (no transformer) 75 mA
Idd2 10BASE-T
(analog core + PLL + digital
core + transceiver + digital I/O)
VDDATX/VDDARX = 3.3V, VDDIO = 1.8V;
Chip only (no transformer) 75 mA
Power Management Mode
Idd3 Power Saving Mode(6) Ethernet cable disconnected & Auto-Neg 70 mA
Idd4 Soft Power Down Mode Set Bit [1:0] = 10 in PMECR register 2 mA
Idd5 Energy Detect Mode At low power state 2 mA
Idd6 Hardware Power Down Mode PWRDN (pin36) is tied to low 0.5 mA
TTL Inputs (VDDIO = 3.3V/2.5V/1.8V)
VIH Input High Voltage 2.0/2.0
/1.3 V
VIL Input Low Voltage 0.8/0.6
/0.3 V
IIN Input Current VIN = GND ~ VDDIO -10 10 µA
TTL Outputs (VDDIO = 3.3V/2.5V/1.8V)
VOH Output High Voltage IOH = -8mA 2.4/1.9
/1.5 V
VOL Output Low Voltage IOL = 8mA 0.4/0.4
/0.2 V
|IOZ| Output Tri-state Leakage 10 µA
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed t o functi on outside its operating rating. Unused inputs must always be tied to a appropriate lo gic voltage l evel (Ground
to VDDIO).
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Electrical Characteristics(4, 5)
Symbol Parameter Condition Min Typ Max Units
100BaseTX Transmit (measured differentially after 1:1 transformer)
VO Peak Differential Output Voltage 100Ω termina tion on the diff. output ±0.95 ±1.05 V
Vimb Output Voltage Imbalance 100Ω termination on the diff. output 2 %
tr, / tf Rise/Fall Time 3 5 ns
Rise/Fall Time Imbalance 0 0.5 ns
Duty Cycle Distortion ±0.25 ns
Overshoot 5 %
VSET Reference Voltage of ISET 0.5 V
Output Jitter Peak-to-peak 0.7 1.4 ns
10BaseT Receive
Vsq Squelch Threshold 5MHz square wave 400 mV
10BaseT Transmit (measured differentially after 1:1 transformer)
Vp Peak Differential Output Voltage 100Ω termination on the differential output 2.2 2.5 2.8 V
Jitter Added 100Ω termina tion on the differ ential output
(Peak-to-peak) 1.8 3.5 ns
Table 15. Electrical Characteristics
Notes:
3. No (HS) heat spreader in this package. The θJC/θJA is under air velocity 0m/s.
4. TA = 25°C. Specification f or packaged product onl y.
5. Single Port ’s transf orm er cons um es an additional 45mA @3.3V for 100BASE-TX and 70mA @3.3V for 10BASE-T.
6. Single Port’s transformer consumes less than 1mA during the Power Saving Mode.
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Timing Specifications
Asynchronous Read and Write Timing
Figure 12. Asynchronous Cycle
Symbol Parameter Min Typ Max Unit
t1 A1-A7, AEN, BExN[3:0] vali d to RDN, WRN active 0 ns
t2 A1-A7, AEN, BExN[3:0] hold after RDN, WRN inactive 0 ns
t3 Read data valid to ARDY rising 0.5 ns
t4 RDN inac tive to Read data invalid 1 2 ns
WRN active to write data valid (bit12=0 in RXFDPR) 8 16 ns
t5 WRN active to write data valid (bit12=1 in RXFDPR) 4 ns
t6 Read or write active to ARDY Low 8 ns
t7 ARDY low (wait time) 24 ns
Read active time (low) 40 ns t8 Write active time (low) 40 ns
Read inactive time (high) 10 ns t9 Write inactive time (high) 10 ns
Table 16. Asynchronous Cycle Timing Parameters
t5
t1
t4
t3
t2
valid
valid
valid
Addr, AEN, BExN
Read D ata
RDN, WRN
Write Data
t6
ARDY t7
t9
t8
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Address Latching Timing for All Modes
Figure 13. Address Latching Cycle for All Modes
Symbol Parameter Min Typ Max Unit
t1 A1-A7, AEN to LDEVN delay 5 ns
Table 17. Address Latching Timing Parameters
t1
A
ddress, AEN, BExN
LDEVN
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Auto Negotiation Timing
Figure 14. Auto Negotiation Timing
Timing Parameter Description Min Typ Max Unit
tBTB FLP burst to FLP burst 8 16 24 ms
tFLPW FLP burst width 2 ms
tPW Clock/Data pulse width 100 ns
tCTD Clock pulse to data pulse 55.5 64 69.5 µs
tCTC Clock pulse to clock pul se 111 128 139 µs
Number of Clock /Data pul se s per burst 17 33
Table 18. Auto Negotiation Timing Parameters
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Reset Timing
As long as the stable supply voltages to reset High timing (minimum of 10ms) are met, there is no power-sequencing
requirement for the KSZ8851M supply voltages (3.3V).
The reset timing requirement is summarized in the Figure 15 and Table 19.
Figure 15. Reset Timing
Symbol Parameter Min Max Unit
tsr Stable supply voltages to r e set High 10 ms
Table 19. Reset Timing Parameters
Supply
Voltage
RSTN
tsr
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EEPROM Timing
EESK
EECS
EEDI
EEDO
High-Z D15 D14 D13 D1 D0
An A0011
1
*1
*1 Start bit
tcyc
ts
th
Figure 16. EEPROM Read Cycle Timing Diagram
Timing Parameter Description Min Typ Max Unit
tcyc Clock cycle 0.8 (OBCR[1:0]=00 on-chip
bus speed @ 125 MHz) μs
ts Setup time 20 ns
th Hold time 20 ns
Table 20. EEPROM Timing Parameters
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Selection of Isolation Transformers
A 1:1 isolation transform er is required at the line interface. An isolation transformer with integrated comm on-mode choke
is recommended for exceeding FCC requirements.
Table 21 gives recommended transformer characteristics.
Parameter Value Test Condition
Turns ratio 1 CT : 1 CT
Open-circuit inductance (min) 350μH 100mV, 100kHz, 8mA
Leakage induct anc e (max) 0.4μH 1MHz (min)
Inter-winding capacitance (max) 12pF
D.C. resistance (max) 0.9Ω
Insertion loss (max) 1.0dB 0MHz – 65MHz
HIPOT (min) 1500Vrms
Table 21. Transformer Selection Criteria
Magnetic Manufacturer Part Number Auto MDI-X Number of Port
Pulse H1102 Yes 1
Pulse (low cost) H1260 Yes 1
Transpower HB726 Yes 1
Bel Fuse S558-5999-U 7 Yes 1
Delta LF8505 Yes 1
LanKom LF-H41S Yes 1
TDK (Mag Jack) TLA-6T718 Yes 1
Table 22. Qualified Single Port Magnetics
Selection of Reference Crystal
Chacteristics Value Units
Frequency 25 MHz
Frequency tolerance (max) ±50 ppm
Load capacitan ce (max) 20 pF
Series resistance 40 Ω
Table 23. Typical Reference Crystal Characteristics
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Package Information
Figure 17. 128-Pin PQFP Package
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Acronyms and Glossary
BIU Bus Interface Unit The host interface function that performs code conversion, buffering,
and the like required for communications to and from a network.
BPDU Bridge Protocol Data Unit A packet containing ports, addresses, etc. to make sure data being
passed through a bridged network arrives at its proper destination.
CMOS Complementary Metal Oxide Semiconductor A common semiconductor manufacturing technique in which positive
and negative types of transistors are combined to form a current gate
that in turn forms an effective means of controlling electrical current
through a chip.
CRC Cyclic Redundancy Check A common technique for detecting data transmission errors. CRC for
Ethernet is 32 bits long.
Cut-through switch A sw itch typically processes received packets by reading in the full
packet (storing), then processing the packet to determine where it
needs to go, then forwarding it. A cut-through switch simply reads in
the first bit of an incoming packet and forwards the packet. Cut-
through switch es do not store t he pack et.
DA Destination Address The address to send packets.
DMA Direct Memory Access A design in which memory on a chip is controlled independently of
the CPU.
EEPROM Electronically Erasable Programmable Read-only Memory A design in which memory on a chip can be erased by exposing it to
an electrical charge.
EISA Extended Industry Standard Architecture A bus architecture designed for PCs using 80x86 processors, or an
Intel 80386, 80486 or Pentium microprocessor. EISA b u ses are 32
bits wide and support mu ltipr o ces sin g.
EMI Electro-Magnetic Interference A naturally occurring phenomena when the electromagnetic field of
one device disrupts, impedes or degrades the electromagnetic field of
another device by coming into proximity with it. In computer
technology, computer devices are susceptible to EMI because
electromagnetic fields are a byproduct of passing electricity through a
wire. Data lines that have not been properly shielded are susceptible
to data corruption by EMI.
FCS Frame Check Sequence See CRC.
FID Frame or Filter ID Specifies the frame identifier. Alternately is the filter identifier.
IGMP Internet Group Management Protocol The protocol defined by RFC 1112 for IP multicast transmissions.
IPG Inter-Packet Gap A time delay between successive data packets mandated by the
network standard for protocol reasons. In Ethernet, the medium has
to be "silent" (i.e., no data transfer) for a short period of time before a
node can consider the network idle and start to transmit. IPG is used
to correct timing differences between a transmitter and receiver.
During the IPG, no data is transferred, and information in the gap can
be discarded or additions inserted without impact on data integrity.
ISI Inter-Symbol Interference The disruption of transmitted code caused by adjacent pulses
affecting or interfering with each other.
ISA Industry Standard Architecture A bus architecture used in the IBM PC/XT and PC/AT.
Jumbo Packet A packet larger than the standard Ethernet packet (1500 bytes).
Large packet sizes allow for more efficient use of bandwidth, lower
overhead, less processing, etc.
MDI Medium Dependent Interface An Ethernet port connection that allows network hubs or switches to
connect to other hubs or switches without a null-modem, or
crossover, cable. MDI provides the standard interface to a particular
media (copper or fiber) and is therefore 'media dependent.'
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MDI-X Medium Dependent Interface Crossover An Ethernet port connection that allow s networked end stations (i.e.,
PCs or workstations) to connect to each other using a null-modem, or
crossover, cable. For 10/100 full-duplex netwo rks, an end point (such
as a computer) and a switch are wired so that each transmitter
connects to the far end receiver. When connecting two computers
together, a cable that crosses the TX and RX is required to do this.
With auto MDI-X, the PHY senses the correct TX and RX roles,
eliminating any cable confusion.
MIB Management Information Base The MIB comprises the management portion of network devices. This
can include things like monitoring traffic levels and faults (statistical),
and can also change operating parameters in network nodes (static
forwarding addresses).
MII Media Independent Interface The MII accesses PHY registers as defined in the IEEE 802.3
specification.
NIC Network Interface Card An expansion board inserted into a computer to allow it to be
connected to a network. Most NICs are designed for a particular type
of network, protocol, and media, although some can serve multiple
networks.
NPVID Non Port VLAN ID The Port VLAN ID value is used as a VLAN reference.
PLL Phase-Locked Loop An electronic cir cuit that c ontrols an oscillator so that it maintains a
constant phase angle (i.e., lock) on the frequency of an input, or
reference, signal. A PLL ensures that a communication signal is
locked on a specific frequency and can also be used to generate,
modulate, and demodulate a signal and divide a frequency.
PME Power Management Event An occurrence that affects the directing of power to different
components of a system.
QMU Queue Management Unit Manages packet traffic between MAC/PHY interface and the system
host. The QMU has built-in packet memories for receive and transmit
functions called TXQ (Transmit Queue) and RXQ (Receive Queue).
SA Source Address The address from which information has been sent.
TDR Time Domain Reflectometry TDR is used to pinpoint flaws and problems in underground and aerial
wire, cabl ing, and fiber optics. They send a signal down the c onductor
and measure the time it takes for the signal -- or part of the signal -- to
return.
UTP Unshielded Twisted Pair Commonly a cable containing 4 twisted pairs of wires. The wires are
twisted in such a manner as to cancel electrical interference
generated in each wire, theref ore shielding is not required.
VLAN Virtual Local Area Network A configuration of co mputers that acts as if all computers are
connected by the sa me phys ical network but which may be located
virtually anywhere.
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The information furnished by Micrel in this data sheet is believed to be accurate and relia ble. However, no responsibility is ass um ed by Micrel fo r its use.
Micrel reserves the right to change circuit ry and specifi cations at any time without notificat i on to the custom er.
Micrel Products are not designed or authorized f or use as components in life support appliances, devic es or sys t ems where malfu nction of a product can
reasonably be expected t o resul t in personal i njury. Li fe support devices or systems are devic es or systems that (a) are intend ed f or surgical impl ant into
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