KSZ8895MQX/RQX/FQX/ML
Integrated 5-Port 10/100 Managed Ethernet
Switch with MII/RMII Interface
Revision 1.1
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
April 28, 2014
Revision-1.1
General Description
The KSZ8895MQX/RQX/FQX/ML is a highly-integrated,
Layer 2 managed, five-port switch with numerous features
designed to reduce system cost. Intended for cost-
sensitive 10/100Mbps five-port switch systems with low
power consumption, on-chip termination, and internal core
power controllers, it supports high-performance memory
bandwidth and shared memory-based switch fabric with
non-blocking configuration. Its extensive feature set
includes power management, programmable rate limit and
priority ratio, tag/port-based VLAN, packets filtering, four-
queue QoS prioritization, management interfaces, and MIB
counters. The KSZ8895 family provides multiple CPU data
interfaces to effectively address both current and emerging
fast Ethernet applications when port 5 is configured to
separate MAC5 with SW5-MII/RMII and PHY5 with P5-
MII/RMII interfaces.
The KSZ8895 family offers three configurations, providing
the flexibility to meet different requirements:
KSZ8895MQX/ML: 5 10/100Base-T/TX transceivers,
1 SW5-MII and 1 P5-MII interface
KSZ8895RQX: 5 10/100Base-T/TX transceivers, 1
SW5-RMII and 1 P5-RMII interface
KSZ8895FQX: 4 10/100Base-T/TX transceivers on
Ports 1, 2, 3 and 5 (port 3 can be set to the fiber
mode). 1 100Base-FX transceivers on Port 4. 1 SW5-
MII and 1 P5-MII interface
All registers of MACs and PHYs units can be managed by
the SPI or the SMI interface. MIIM registers can be
accessed through the MDC/MDIO interface. EEPROM can
set all control registers for the unmanaged mode.
KSZ8895MQX/RQX/FQX are 128-pin PQFP package.
KSZ8895ML is 128-pin LQFP package.
Datasheets and support documentation are available on
Micrel’s web site at: www.micrel.com.
Functional Diagram
Note: SW5 indicates the MAC5 of the switch side, P5 indicates the PHY5 of the Port 5.
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
2
Revision-1.1
Features
Advanced Switch Features
IEEE 802.1q VLAN support for up to 128 active VLAN
groups (full-range 4096 of VLAN IDs).
Static MAC table supports up to 32 entries.
VLAN ID tag/untag options, per port basis
IEEE 802.1p/q tag insertion or removal on a per port
basis based on ingress port (egress).
Programmable rate limiting at the ingress and egress
on a per port basis.
Jitter-free per packet based rate limiting support.
Broadcast storm protection with percentage control
(global and per port basis).
IEEE 802.1d rapid spanning tree protocol RSTP
support.
Tail tag mode (1 byte added before FCS) support at
Port 5 to inform the processor which ingress port
receives the packet.
1.4Gbps high-performance memory bandwidth and
shared memory-based switch fabric with fully non-
blocking configuration.
Dual MII with MAC5 and PHY5 on port 5, SW5-
MII/RMII for MAC 5 and P5-MII/RMII for PHY 5.
Enable/Disable option for huge frame size up to 2000
Bytes per frame.
IGMP v1/v2 snooping (Ipv4) support for multicast
packet filtering.
IPv4/IPv6 QoS support.
Support unknown unicast/multicast address and
unknown VID packet filtering.
Self-address filtering.
Comprehensive Configuration Register Access
Serial management interface (MDC/MDIO) to all PHYs
registers and SMI interface (MDC/MDIO) to all registers.
High speed SPI (up to 25MHz) and I2C master
Interface to all internal registers.
I/0 pins strapping and EEPROM to program selective
registers in unmanaged switch mode.
Control registers configurable on the fly (port-priority,
802.1p/d/q, AN and so on).
QoS/CoS Packet Prioritization Support
Per port, 802.1p and DiffServ-based.
1/2/4-queue QoS prioritization selection.
Programmable weighted fair queuing for ratio control.
Re-mapping of 802.1p priority field per port basis.
Integrated Five-Port 10/100 Ethernet Switch
New generation switch with five MACs and five PHYs
with fully compliant with IEEE 802.3u standard.
PHYs designed with patented enhanced mixed-signal
technology.
Non-blocking switch fabric assures fast packet delivery
by utilizing a 1K MAC address lookup table and a store-
and-forward architecture.
On-chip 64Kbyte memory for frame buffering (not
shared with 1K unicast address table).
Full duplex IEEE 802.3x flow control (PAUSE) with
force mode option.
Half-duplex back pressure flow control.
HP Auto MDI/MDI-X and IEEE Auto crossover support.
SW-MII interface supports both MAC mode and PHY
mode.
7-wire serial network interface (SNI) support for legacy
MAC.
Per port LED Indicators for link, activity, and 10/100
speed.
Register port status support for link, activity, full/half
duplex and 10/100 speed.
Micrel LinkMD® cable diagnostic capabilities.
On-chip terminations and internal biasing technology
for cost down and lowest power consumption.
Switch Monitoring Features
Port mirroring/monitoring/sniffing: ingress and/or egress
traffic to any port or MII.
MIB counters for fully compliant statistics gathering 34
MIB counters per port.
Loop-back support for MAC, PHY and remote
diagnostic of failure.
Interrupt for the link change on any ports.
Low Power Dissipation
Full-chip hardware power-down.
Full-chip software power-down and per port software
power down.
Energy-detect mode support < 100mW full chip-power
consumption when all ports have no activity.
Very low full chip power consumption (<0.5W) in
standalone 5-port, without extra power consumption on
transformers.
Dynamic clock tree shutdown feature.
Voltages: Single 3.3V supply with 3.3V VDDIO and
Internal 1.2V LDO controller enabled, or external 1.2V
LDO solution.
– Analog VDDAT 3.3V only.
– VDDIO support 3.3V, 2.5V and 1.8V.
– Low 1.2V core power .
0.11µm CMOS technology.
Commercial temperature range: 0°C to +70°C.
Industrial Temperature Range: -40°C to +85°C.
128-pin PQFP and 128-pin LQFP, lead-free package.
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
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Revision-1.1
Applications
Typical
VOIP phone
Set-top/game box
Automotive
Industrial control
IPTV POF
SOHO residential gateway
Broadband gateway/firewall/VPN
Integrated DSL/cable modem
Wireless LAN access point + gateway
Standalone 10/100 5-port switch
Ordering Information
Part Number
Temperature Range
Package
Lead Finish/Grade
KSZ8895MQXCA
0°C to 70°C
128-Pin PQFP
Pb-Free/Commercial
KSZ8895MQXIA
-40°C to +85°C
128-Pin PQFP
Pb-Free/Industrial
KSZ8895RQXCA
0°C to 70°C
128-Pin PQFP
Pb-Free/Commercial
KSZ8895RQXIA
-40°C to +85°C
128-Pin PQFP
Pb-Free/Industrial
KSZ8895FQXCA
0°C to 70°C
128-Pin PQFP
Pb-Free/Commercial
KSZ8895FQXIA
-40°C to +85°C
128-Pin PQFP
Pb-Free/Industrial
KSZ8895ML
0°C to 70°C
128-Pin LQFP
Pb-Free/Commercial
KSZ8895MLI(1)
-40°C to +85°C
128-Pin LQFP
Pb-Free/Industrial
KSZ8895MQX-EVAL
Evaluation Board for KSZ8895MQX
KSZ8895RQX-EVAL
Evaluation Board for KSZ8895RQX
KSZ8895FQX-EVAL
Evaluation Board for KSZ8895FQX
KSZ8895ML-EVAL
Evaluation Board for KSZ8895ML
Note:
1. Please consult sales regarding availability.
Revision History
Revision
Date
Description
1.0
O2/21/14
Initial document created
1.1
04/28/14
Update description for Register 1 bits [7:4], update the descriptions
in the section of the internal 1.2V LDO controller. Update the pin
125/pin126 descriptions. Add evaluation boards in ordering
information.
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April 28, 2014
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Revision-1.1
Contents
General Description......................................................................................................................................................... 1
Functional Diagram ......................................................................................................................................................... 1
Applications ..................................................................................................................................................................... 3
Ordering Information ....................................................................................................................................................... 3
Revision History .............................................................................................................................................................. 3
System Level Application .............................................................................................................................................. 15
Pin Configuration ........................................................................................................................................................... 17
Pin Description .............................................................................................................................................................. 19
Pin for Strap-in Options ................................................................................................................................................. 27
Introduction .................................................................................................................................................................... 31
Functional Overview: Physical Layer Transceiver ........................................................................................................ 31
100BASE-TX Transmit .............................................................................................................................................. 31
100BASE-TX Receive ............................................................................................................................................... 31
PLL Clock Synthesizer............................................................................................................................................... 32
Scrambler/Descrambler (100BASE-TX only) ............................................................................................................ 32
100BASE-FX Operation ............................................................................................................................................ 32
100BASE-FX Signal Detection .................................................................................................................................. 32
100BASE-FX Far End Fault ...................................................................................................................................... 32
10BASE-T Transmit ................................................................................................................................................... 32
10BASE-T Receive .................................................................................................................................................... 32
MDI/MDI-X Auto Crossover ....................................................................................................................................... 32
Straight Cable ........................................................................................................................................................ 33
Crossover Cable .................................................................................................................................................... 34
Auto-Negotiation ........................................................................................................................................................ 34
LinkMD® Cable Diagnostics ....................................................................................................................................... 36
Access .................................................................................................................................................................... 36
Usage ..................................................................................................................................................................... 36
A LinkMD example ................................................................................................................................................. 37
On-chip Termination Resistors .................................................................................................................................. 37
Internal 1.2V LDO Controller ..................................................................................................................................... 37
Functional Overview: Power ......................................................................................................................................... 38
Using Internal 1.2V LDO Controller ........................................................................................................................... 38
Using External 1.2V LDO Regulator .......................................................................................................................... 39
Functional Overview: Power Management ................................................................................................................... 40
Normal Operation Mode ............................................................................................................................................ 40
Energy Detect Mode .................................................................................................................................................. 40
Soft Power Down Mode ............................................................................................................................................. 41
Power Saving Mode................................................................................................................................................... 41
Port-based Power Down Mode .................................................................................................................................. 41
Functional Overview: Switch Core ................................................................................................................................ 41
Address Look-Up ....................................................................................................................................................... 41
Learning ..................................................................................................................................................................... 41
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Revision-1.1
Migration .................................................................................................................................................................... 41
Aging .......................................................................................................................................................................... 42
Forwarding ................................................................................................................................................................. 42
KSZ8895MQX/RQX/FQX/ML will not forward the following packets: .................................................................... 42
Switching Engine ....................................................................................................................................................... 42
Media Access Controller (MAC) Operation ............................................................................................................... 42
Inter-Packet Gap (IPG) .......................................................................................................................................... 42
Backoff Algorithm ................................................................................................................................................... 42
Late Collision .......................................................................................................................................................... 42
Illegal Frames ......................................................................................................................................................... 42
Flow Control ........................................................................................................................................................... 42
Half-Duplex Back Pressure .................................................................................................................................... 44
Broadcast Storm Protection ................................................................................................................................... 45
MII Interface Operation .............................................................................................................................................. 46
Port 5 PHY 5 P5-MII/RMII Interface .......................................................................................................................... 46
Port 5 MAC 5 Switch SW5-RMII Interface for the KSZ8895RQX ............................................................................. 48
SNI Interface Operation ............................................................................................................................................. 50
Advanced Functionality ................................................................................................................................................. 51
QoS Priority Support .................................................................................................................................................. 51
Port-Based Priority ................................................................................................................................................. 51
802.1p-Based Priority ............................................................................................................................................ 51
DiffServ-Based Priority ........................................................................................................................................... 52
Spanning Tree Support ............................................................................................................................................. 52
Rapid Spanning Tree Support ................................................................................................................................... 53
Tail Tagging Mode ..................................................................................................................................................... 54
IGMP Support ............................................................................................................................................................ 55
IGMP Snooping ...................................................................................................................................................... 55
IGMP Send Back to the Subscribed Port ............................................................................................................... 55
Port Mirroring Support ............................................................................................................................................... 55
“Receive Only” mirror on a port .............................................................................................................................. 55
“Transmit Only” mirror on a port ............................................................................................................................. 55
“Receive and Transmit” mirror on two ports .......................................................................................................... 55
VLAN Support ............................................................................................................................................................ 55
Rate Limiting Support ................................................................................................................................................ 56
Ingress Rate Limit .................................................................................................................................................. 56
Egress Rate Limit ................................................................................................................................................... 57
Transmit Queue Ratio Programming ..................................................................................................................... 57
Filtering for Self-Address, Unknown Unicast/Multicast Address and Unknown VID Packet/IP Multicast ................. 57
Configuration Interface .................................................................................................................................................. 57
I2C Master Serial Bus Configuration .......................................................................................................................... 57
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SPI Slave Serial Bus Configuration ....................................................................................................................... 58
MII Management Interface (MIIM).......................................................................................................................... 61
Serial Management Interface (SMI) ....................................................................................................................... 61
Register Description ...................................................................................................................................................... 63
Global Registers ........................................................................................................................................................ 65
Register 0 (0x00): Chip ID0 ................................................................................................................................... 65
Register 1 (0x01): Chip ID1 / Start Switch ............................................................................................................. 65
Register 2 (0x02): Global Control 0 ....................................................................................................................... 65
Register 3 (0x03): Global Control 1 ....................................................................................................................... 66
Register 4 (0x04): Global Control 2 ....................................................................................................................... 67
Register 5 (0x05): Global Control 3 ....................................................................................................................... 68
Register 6 (0x06): Global Control 4 ....................................................................................................................... 69
Register 7 (0x07): Global Control 5 ....................................................................................................................... 70
Register 8 (0x08): Global Control 6 ....................................................................................................................... 70
Register 9 (0x09): Global Control 7 ....................................................................................................................... 70
Register 10 (0x0A): Global Control 8 ..................................................................................................................... 71
Register 11 (0x0B): Global Control 9 ..................................................................................................................... 71
Register 12 (0x0C): Global Control 10 ................................................................................................................... 72
Register 13 (0x0D): Global Control 11 ................................................................................................................... 72
Register 14 (0x0E): Power Down Management Control 1 ..................................................................................... 72
Register 15 (0x0F): Power Down Management Control 2 ..................................................................................... 73
Port Registers ............................................................................................................................................................ 74
Register 16 (0x10): Port 1 Control 0 ...................................................................................................................... 74
Register 32 (0x20): Port 2 Control 0 ...................................................................................................................... 74
Register 48 (0x30): Port 3 Control 0 ...................................................................................................................... 74
Register 64 (0x40): Port 4 Control 0 ...................................................................................................................... 74
Register 80 (0x50): Port 5 Control 0 ...................................................................................................................... 74
Register 17 (0x11): Port 1 Control 1 ...................................................................................................................... 75
Register 33 (0x21): Port 2 Control 1 ...................................................................................................................... 75
Register 49 (0x31): Port 3 Control 1 ...................................................................................................................... 75
Register 65 (0x41): Port 4 Control 1 ...................................................................................................................... 75
Register 81 (0x51): Port 5 Control 1 ...................................................................................................................... 75
Register 18 (0x12): Port 1 Control 2 ...................................................................................................................... 76
Register 34 (0x22): Port 2 Control 2 ...................................................................................................................... 76
Register 50 (0x32): Port 3 Control 2 ...................................................................................................................... 76
Register 66 (0x42): Port 4 Control 2 ...................................................................................................................... 76
Register 82 (0x52): Port 5 Control 2 ...................................................................................................................... 76
Register 19 (0x13): Port 1 Control 3 ...................................................................................................................... 77
Register 35 (0x23): Port 2 Control 3 ...................................................................................................................... 77
Register 51 (0x33): Port 3 Control 3 ...................................................................................................................... 77
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
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Revision-1.1
Register 67 (0x43): Port 4 Control 3 ...................................................................................................................... 77
Register 83 (0x53): Port 5 Control 3 ...................................................................................................................... 77
Register 20 (0x14): Port 1 Control 4 ...................................................................................................................... 77
Register 36 (0x24): Port 2 Control 4 ...................................................................................................................... 77
Register 52 (0x34): Port 3 Control 4 ...................................................................................................................... 77
Register 68 (0x44): Port 4 Control 4 ...................................................................................................................... 77
Register 84 (0x54): Port 5 Control 4 ...................................................................................................................... 77
Register 87 (0x57): RMII Management Control Register ...................................................................................... 77
Register 25 (0x19): Port 1 Status 0........................................................................................................................ 78
Register 41 (0x29): Port 2 Status 0........................................................................................................................ 78
Register 57 (0x39): Port 3 Status 0........................................................................................................................ 78
Register 73 (0x49): Port 4 Status 0........................................................................................................................ 78
Register 89 (0x59): Port 5 Status 0........................................................................................................................ 78
Register 26 (0x1A): Port 1 PHY Special Control/Status ........................................................................................ 78
Register 42 (0x2A): Port 2 PHY Special Control/Status ........................................................................................ 78
Register 58 (0x3A): Port 3 PHY Special Control/Status ........................................................................................ 78
Register 74 (0x4A): Port 4 PHY Special Control/Status ........................................................................................ 78
Register 90 (0x5A): Port 5 PHY Special Control/Status ........................................................................................ 78
Register 27 (0x1B): Port 1 LinkMD result .............................................................................................................. 79
Register 43 (0x2B): Port 2 LinkMD result .............................................................................................................. 79
Register 59 (0x3B): Port 3 LinkMD result .............................................................................................................. 79
Register 75 (0x4B): Port 4 LinkMD result .............................................................................................................. 79
Register 91 (0x5B): Port 5 LinkMD result .............................................................................................................. 79
Register 28 (0x1C): Port 1 Control 5...................................................................................................................... 79
Register 44 (0x2C): Port 2 Control 5...................................................................................................................... 79
Register 60 (0x3C): Port 3 Control 5...................................................................................................................... 79
Register 76 (0x4C): Port 4 Control 5...................................................................................................................... 79
Register 92 (0x5C): Port 5 Control 5...................................................................................................................... 79
Register 29 (0x1D): Port 1 Control 6...................................................................................................................... 81
Register 45 (0x2D): Port 2 Control 6...................................................................................................................... 81
Register 61 (0x3D): Port 3 Control 6...................................................................................................................... 81
Register 77 (0x4D): Port 4 Control 6...................................................................................................................... 81
Register 93 (0x5D): Port 5 Control 6...................................................................................................................... 81
Register 30 (0x1E): Port 1 Status 1 ....................................................................................................................... 82
Register 46 (0x2E): Port 2 Status 1 ....................................................................................................................... 82
Register 62 (0x3E): Port 3 Status 1 ....................................................................................................................... 82
Register 78 (0x4E): Port 4 Status 1 ....................................................................................................................... 82
Register 94 (0x5E): Port 5 Status 1 ....................................................................................................................... 82
Register 31 (0x1F): Port 1 Control 7 and Status 2 ................................................................................................. 82
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
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Revision-1.1
Register 47 (0x2F): Port 2 Control 7 and Status 2 ................................................................................................. 82
Register 63 (0x3F): Port 3 Control 7 and Status 2 ................................................................................................. 82
Register 79 (0x4F): Port 4 Control 7 and Status 2 ................................................................................................. 82
Register 95 (0x5F): Port 5 Control 7 and Status 2 ................................................................................................. 82
Advanced Control Registers ...................................................................................................................................... 83
Register 104 (0x68): MAC Address Register 0 ...................................................................................................... 83
Register 105 (0x69): MAC Address Register 1 ...................................................................................................... 83
Register 106 (0x6A): MAC Address Register 2 ..................................................................................................... 83
Register 107 (0x6B): MAC Address Register 3 ..................................................................................................... 83
Register 108 (0x6C): MAC Address Register 4 ..................................................................................................... 83
Register 109 (0X6D): MAC Address Register 5 .................................................................................................... 83
Register 110 (0x6E): Indirect Access Control 0 ..................................................................................................... 84
Register 111 (0x6F): Indirect Access Control 1 ..................................................................................................... 84
Register 112 (0x70): Indirect Data Register 8 ....................................................................................................... 84
Register 113 (0x71): Indirect Data Register 7 ....................................................................................................... 84
Register 114 (0x72): Indirect Data Register 6 ....................................................................................................... 84
Register 115 (0x73): Indirect Data Register 5 ....................................................................................................... 84
Register 116 (0x74): Indirect Data Register 4 ....................................................................................................... 84
Register 117 (0x75): Indirect Data Register 3 ....................................................................................................... 84
Register 118 (0x76): Indirect Data Register 2 ....................................................................................................... 84
Register 119 (0x77): Indirect Data Register 1 ....................................................................................................... 84
Register 120 (0x78): Indirect Data Register 0 ....................................................................................................... 84
Register 124 (0x7C): Interrupt Status Register ...................................................................................................... 85
Register 125 (0x7D): Interrupt Mask Register ....................................................................................................... 85
Register 128 (0x80): Global Control 12 ................................................................................................................. 86
Register 129 (0x81): Global Control 13 ................................................................................................................. 86
Register 130 (0x82): Global Control 14 ................................................................................................................. 86
Register 131 (0x83): Global Control 15 ................................................................................................................. 88
Register 132 (0x84): Global Control 16 ................................................................................................................. 88
Register 133(0x85): Global Control 17 .................................................................................................................. 88
Register 134 (0x86): Global Control 18 ................................................................................................................. 89
Register 135 (0x87): Global Control 19 ................................................................................................................. 89
Register 144 (0x90): TOS Priority Control Register 0............................................................................................ 90
Register 145 (0x91): TOS Priority Control Register 1............................................................................................ 90
Register 146 (0x92): TOS Priority Control Register 2............................................................................................ 90
Register 147 (0x93): TOS Priority Control Register 3............................................................................................ 90
Register 148 (0x94): TOS Priority Control Register 4............................................................................................ 90
Register 149 (0x95): TOS Priority Control Register 5............................................................................................ 91
Register 150 (0x96): TOS Priority Control Register 6............................................................................................ 91
Micrel, Inc.
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Revision-1.1
Register 151 (0x97): TOS Priority Control Register 7............................................................................................ 91
Register 152 (0x98): TOS Priority Control Register 8............................................................................................ 91
Register 153 (0x99): TOS Priority Control Register 9............................................................................................ 91
Register 154 (0x9A): TOS Priority Control Register 10 ......................................................................................... 91
Register 155 (0x9B): TOS Priority Control Register 11 ......................................................................................... 91
Register 156 (0x9C): TOS Priority Control Register 12 ......................................................................................... 92
Register 157 (0x9D): TOS Priority Control Register 13 ......................................................................................... 92
Register 158 (0x9E): TOS Priority Control Register 14 ......................................................................................... 92
Register 159 (0x9F): TOS Priority Control Register 15 ......................................................................................... 92
Register 165 (0xA5): Reserved .............................................................................................................................. 92
Register 176 (0xB0): Port 1 Control 8 .................................................................................................................... 92
Register 192 (0xC0): Port 2 Control 8.................................................................................................................... 92
Register 208 (0xD0): Port 3 Control 8.................................................................................................................... 92
Register 224 (0xE0): Port 4 Control 8 .................................................................................................................... 92
Register 240 (0xF0): Port 5 Control 8 .................................................................................................................... 92
Register 177 (0xB1): Port 1 Control 9 .................................................................................................................... 93
Register 193 (0xC1): Port 2 Control 9.................................................................................................................... 93
Register 209 (0xD1): Port 3 Control 9.................................................................................................................... 93
Register 225 (0xE1): Port 4 Control 9 .................................................................................................................... 93
Register 241 (0xF1): Port 5 Control 9 .................................................................................................................... 93
Register 178 (0xB2): Port 1 Control 10 .................................................................................................................. 94
Register 194 (0xC2): Port 2 Control 10 ................................................................................................................. 94
Register 210 (0xD2): Port 3 Control 10 ................................................................................................................. 94
Register 226 (0xE2): Port 4 Control 10 .................................................................................................................. 94
Register 242 (0xF2): Port 5 Control 10 .................................................................................................................. 94
Register 179 (0xB3): Port 1 Control 11 .................................................................................................................. 94
Register 195 (0xC3): Port 2 Control 11 ................................................................................................................. 94
Register 211 (0xD3): Port 3 Control 11 ................................................................................................................. 94
Register 227 (0xE3): Port 4 Control 11 .................................................................................................................. 94
Register 243 (0xF3): Port 5 Control 11 .................................................................................................................. 94
Register 180 (0xB4): Port 1 Control 12 .................................................................................................................. 94
Register 196 (0xC4): Port 2 Control 12 ................................................................................................................. 94
Register 212 (0xD4): Port 3 Control 12 ................................................................................................................. 94
Register 228 (0xE4): Port 4 Control 12 .................................................................................................................. 94
Register 244 (0xF4): Port 5 Control 12 .................................................................................................................. 94
Register 181 (0xB5): Port 1 Control 13 .................................................................................................................. 95
Register 197 (0xC5): Port 2 Control 13 ................................................................................................................. 95
Register 213 (0xD5): Port 3 Control 13 ................................................................................................................. 95
Register 229 (0xE5): Port 4 Control 13 .................................................................................................................. 95
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
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Revision-1.1
Register 245 (0xF5): Port 5 Control 13 .................................................................................................................. 95
Register 182 (0xB6): Port 1 Rate Limit Control ..................................................................................................... 95
Register 198 (0xC6): Port 2 Rate Limit Control ..................................................................................................... 95
Register 214 (0xD6): Port 3 Rate Limit Control ..................................................................................................... 95
Register 230 (0xE6): Port 4 Rate Limit Control ..................................................................................................... 95
Register 246 (0xF6): Port 5 Rate Limit Control ...................................................................................................... 95
Register 183 (0xB7): Port 1 Priority 0 Ingress Limit Control 1 ............................................................................... 96
Register 199 (0xC7): Port 2 Priority 0 Ingress Limit Control 1 ............................................................................... 96
Register 215 (0xD7): Port 3 Priority 0 Ingress Limit Control 1 ............................................................................... 96
Register 231 (0xE7): Port 4 Priority 0 Ingress Limit Control 1 ............................................................................... 96
Register 247 (0xF7): Port 5 Priority 0 Ingress Limit Control 1 ............................................................................... 96
Register 184 (0xB8): Port 1 Priority 1 Ingress Limit Control 2 ............................................................................... 96
Register 200 (0xC8): Port 2 Priority 1 Ingress Limit Control 2 ............................................................................... 96
Register 216 (0xD8): Port 3 Priority 1 Ingress Limit Control 2 ............................................................................... 96
Register 232 (0xE8): Port 4 Priority 1 Ingress Limit Control 2 ............................................................................... 96
Register 248 (0xF8): Port 5 Priority 1 Ingress Limit Control 2 ............................................................................... 96
Register 185 (0xB9): Port 1 Priority 2 Ingress Limit Control 3 ............................................................................... 96
Register 201 (0xC9): Port 2 Priority 2 Ingress Limit Control 3 ............................................................................... 96
Register 217 (0xD9): Port 3 Priority 2 Ingress Limit Control 3 ............................................................................... 96
Register 233 (0xE9): Port 4 Priority 2 Ingress Limit Control 3 ............................................................................... 96
Register 249 (0xF9): Port 5 Priority 2 Ingress Limit Control 3 ............................................................................... 96
Register 186 (0xBA): Port 1 Priority 3 Ingress Limit Control 4 .............................................................................. 97
Register 202 (0xCA): Port 2 Priority 3 Ingress Limit Control 4 .............................................................................. 97
Register 218 (0xDA): Port 3 Priority 3 Ingress Limit Control 4 .............................................................................. 97
Register 234 (0xEA): Port 4 Priority 3 Ingress Limit Control 4 .............................................................................. 97
Register 250 (0xFA): Port 5 Priority 3 Ingress Limit Control 4 ............................................................................... 97
Register 187 (0xBB): Port 1 Queue 0 Egress Limit Control 1 ............................................................................... 97
Register 203 (0xCB): Port 2 Queue 0 Egress Limit Control 1 ............................................................................... 97
Register 219 (0xDB): Port 3 Queue 0 Egress Limit Control 1 ............................................................................... 97
Register 235 (0xEB): Port 4 Queue 0 Egress Limit Control 1 ............................................................................... 97
Register 251 (0xFB): Port 5 Queue 0 Egress Limit Control 1 ................................................................................ 97
Register 188 (0xBC) : Port 1 Queue 1 Egress Limit Control 2 .............................................................................. 97
Register 204 (0xCC) : Port 2 Queue 1 Egress Limit Control 2 .............................................................................. 97
Register 220 (0xDC) : Port 3 Queue 1 Egress Limit Control 2 .............................................................................. 97
Register 236 (0xEC) : Port 4 Queue 1 Egress Limit Control 2 .............................................................................. 97
Register 252 (0xFC) : Port 5 Queue 1 Egress Limit Control 2 .............................................................................. 97
Register 189 (0xBD): Port 1 Queue 2 Egress Limit Control 3 ............................................................................... 98
Register 205 (0xCD): Port 2 Queue 2 Egress Limit Control 3 ............................................................................... 98
Register 221 (0xDD): Port 3 Queue 2 Egress Limit Control 3 ............................................................................... 98
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
11
Revision-1.1
Register 237 (0xED): Port 4 Queue 2 Egress Limit Control 3 ............................................................................... 98
Register 253 (0xFD): Port 5 Queue 2 Egress Limit Control 3 ............................................................................... 98
Data Rate Limit Selection Limit Table ....................................................................................................................... 99
Register 191(0xBF): Testing Register 1 ................................................................................................................ 99
Register 207(0xCF): Reserved Control Register .................................................................................................. 99
Register 223(0xDF): Testing Register 2 ................................................................................................................ 99
Register 239(0xEF): Port 3 Copper or Fiber Control ............................................................................................. 99
Register 255(0xFF): Testing Register 3 ................................................................................................................. 99
Static MAC Address Table .......................................................................................................................................... 100
Format of Static MAC Table for Reads (32 entries) ................................................................................................ 100
Format of Static MAC Table for Writes (32 entries) ................................................................................................ 100
Dynamic MAC Address Table ..................................................................................................................................... 104
Format of Dynamic MAC Address Table (1K entries) ............................................................................................. 104
MIB (Management Information Base) Counters ......................................................................................................... 106
For Port 1 ............................................................................................................................................................. 106
For port 2, the base is 0x20, same offset definition (0x20-0x3f) .......................................................................... 107
For port 3, the base is 0x40, same offset definition (0x40-0x5f) .......................................................................... 107
For port 4, the base is 0x60, same offset definition (0x60-0x7f) .......................................................................... 107
For port 5, the base is 0x80, same offset definition (0x80-0x9f) .......................................................................... 107
Format of Per Port MIB Counters (16 entries) ......................................................................................................... 107
Format of All Port Dropped Packet MIB Counters ................................................................................................... 107
MIIM Registers ............................................................................................................................................................ 109
Register 0h: MII Control ........................................................................................................................................... 109
Register 1h: MII Status ............................................................................................................................................ 110
Register 2h: PHYID HIGH ....................................................................................................................................... 110
Register 3h: PHYID LOW ........................................................................................................................................ 110
Register 4h: Advertisement Ability ........................................................................................................................... 110
Register 5h: Link Partner Ability .............................................................................................................................. 111
Register 1dh: LinkMD Control/Status ..................................................................................................................... 111
Register 1fh: PHY Special Control/Status ............................................................................................................... 112
Absolute Maximum Ratings(1) ...................................................................................................................................... 113
Operating Ratings(2) .................................................................................................................................................... 113
Electrical Characteristics(4,5) ........................................................................................................................................ 113
Timing Diagrams ......................................................................................................................................................... 115
EEPROM Timing ..................................................................................................................................................... 115
SNI Timing ............................................................................................................................................................... 116
MII Timing ................................................................................................................................................................ 117
SPI Timing ............................................................................................................................................................... 120
Auto-Negotiation Timing .......................................................................................................................................... 122
MDC/MDIO Timing .................................................................................................................................................. 123
Reset Timing ............................................................................................................................................................ 124
Reset Circuit Diagram.............................................................................................................................................. 125
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
12
Revision-1.1
Selection of Isolation Transformer(1)............................................................................................................................ 126
Selection of Reference Crystal .................................................................................................................................... 126
..................................................................................................................................................................................... 128
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
13
Revision-1.1
List of Figures
Figure 1. Broadband Gateway ..................................................................................................................................... 15
Figure 2. Integrated Broadband Router ....................................................................................................................... 15
Figure 3. Standalone Switch ........................................................................................................................................ 16
Figure 4. Using KSZ8895FQX for Dual Media Converter ............................................................................................. 16
Figure 5. Typical Straight Cable Connection ................................................................................................................ 33
Figure 6. Typical Crossover Cable Connection ............................................................................................................ 34
Figure 7. Auto-Negotiation ............................................................................................................................................ 35
Figure 8. Recommended 1.2V Power Connection using Internal 1.2V LDO Controller .............................................. 38
Figure 9. Recommended 1.2V Power Connection Using the External 1.2V Regulator ............................................... 39
Figure 10. Destination Address Lookup Flow Chart, Stage 1 ....................................................................................... 43
Figure 11. Destination Address Resolution Flow Chart, Stage 2 .................................................................................. 44
Figure 12. 802.1p Priority Field Format........................................................................................................................ 51
Figure 13. Tail Tag Frame Format ................................................................................................................................ 54
Figure 14. KSZ8895MQX/RQX/FQX/ML EEPROM Configuration Timing Diagram .................................................... 58
Figure 15. SPI Write Data Cycle .................................................................................................................................. 59
Figure 16. SPI Read Data Cycle .................................................................................................................................. 59
Figure 17. SPI Multiple Write ....................................................................................................................................... 60
Figure 18. SPI Multiple Read ....................................................................................................................................... 60
Figure 19. EEPROM Interface Input Receive Timing Diagram ................................................................................... 115
Figure 20. EEPROM Interface Output Transmit Timing Diagram .............................................................................. 115
Figure 21. SNI Input Timing ........................................................................................................................................ 116
Figure 22. SNI Output Timing ..................................................................................................................................... 116
Figure 23. MAC Mode MII Timing – Data Received from MII ..................................................................................... 117
Figure 24. MAC Mode MII Timing – Data Transmitted from MII ................................................................................. 117
Figure 25. PHY Mode MII Timing – Data Received from MII ...................................................................................... 118
Figure 26. PHY Mode MII Timing – Data Transmitted from MII .................................................................................. 118
Figure 27. RMII Timing – Data Received from RMII ................................................................................................... 119
Figure 28. RMII Timing – Data Transmitted to RMII ................................................................................................... 119
Figure 29. SPI Input Timing ........................................................................................................................................ 120
Figure 30. SPI Output Timing ...................................................................................................................................... 121
Figure 31: Auto-Negotiation Timing ............................................................................................................................ 122
Figure 32. MDC/MDIO Timing ..................................................................................................................................... 123
Figure 33. Reset Timing .............................................................................................................................................. 124
Figure 34. Recommended Reset Circuit ..................................................................................................................... 125
Figure 35. Recommended Circuit for Interfacing with CPU/FPGA Reset ................................................................... 125
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
14
Revision-1.1
List of Tables
Table 1. MDI/MDI-X Pin Definitions .......................................................................................................................... 33
Table 2. Voltages and Power Pins ........................................................................................................................... 38
Table 3. Internal Function Block Status ..................................................................................................................... 40
Table 4. Port 5 PHY P5-MII/RMII Signals ................................................................................................................. 46
Table 5. Switch MAC5 MII Signals ............................................................................................................................ 47
Table 6. Port 5 MAC5 SW5-RMII Connection ........................................................................................................... 49
Table 7. SNI Signals ................................................................................................................................................. 50
Table 8. Tail Tag Rules ............................................................................................................................................ 54
Table 9. FID+DA Look-Up in the VLAN Mode .......................................................................................................... 56
Table 10. FID+SA Look-Up in the VLAN Mode ........................................................................................................ 56
Table 11. SPI Connections ....................................................................................................................................... 59
Table 12. MII Management Interface Frame Format ................................................................................................ 61
Table 13. Serial Management Interface (SMI) Frame Format ................................................................................. 61
Table 14. 10/100BT Rate Selection for the Rate limit ............................................................................................... 99
Table 15. Static MAC Address Table ...................................................................................................................... 100
Table 16. VLAN Table ............................................................................................................................................. 102
Table 17. VLAN ID and Indirect Registers .............................................................................................................. 103
Table 18. Dynamic MAC Address Table ................................................................................................................. 104
Table 19. Port1 MIB Counter Indirect Memory Offerts ........................................................................................... 106
Table 20. Format of “Per Port” MIB Counter .......................................................................................................... 107
Table 21. All Port Dropped Packet MIB Counters .................................................................................................. 107
Table 22. Format of “All Dropped Packet” MIB Counter......................................................................................... 107
Table 23. EEPROM Timing Parameters................................................................................................................. 115
Table 24. SNI Timing Parameters ........................................................................................................................... 116
Table 25. MAC Mode MII Timing Parameters ......................................................................................................... 117
Table 26. PHY Mode MII Timing Parameters .......................................................................................................... 118
Table 27. RMII Timing Parameters .......................................................................................................................... 119
Table 28. SPI Input Timing Parameters .................................................................................................................. 120
Table 29. SPI Output Timing Parameters................................................................................................................ 121
Table 30. Auto-Negotiation Timing Parameters ...................................................................................................... 122
Table 31. MDC/MDIO Typical Timing Parameters .................................................................................................. 123
Table 32. Reset Timing Parameters ....................................................................................................................... 124
Table 33. Transformer Selection Criteria................................................................................................................. 126
Table 34. Qualified Magnetic Vendors ................................................................................................................... 126
Table 35. Typical Reference Crystal Characteristics ............................................................................................. 126
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
15
Revision-1.1
System Level Application
Figure 1. Broadband Gateway
Figure 2. Integrated Broadband Router
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
16
Revision-1.1
Figure 3. Standalone Switch
Figure 4. Using KSZ8895FQX for Dual Media Converter
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
17
Revision-1.1
Pin Configuration
TXM5
VDDAT
FXSD3
TXP5
33
34
35
36
37
38
KSZ8895MQX/RQX/FQX
(Top View) NC
PMRXDV/PMCRSDV
NC
NC
NC
NC
NC
NC
PWRDN_N
INTR_N
GNDD
VDDC
PMTXEN
PMTXD3
PMTXD2
PMTXD1
PMTXD0
PMTXER
PMTXC/PMREFCLK
GNDD
PMRXD1
VDDIO
PMRXC
PMRXD3
PMRXD263
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
64
FXSD4
LED3-1
LED4-0
LED3-2
SCONF1
SCOL
SMRXD2
VDDIO
SMTXC/SMREFCLK
SMTXD0
SMTXD2
SMTXEN
PCOL
PCRS
PMRXER
LED4-1
LED4-2
LED5-1
LED5-2
VDDC
GNDD
SCONF0
SCRS
SMRXD0
SMRXD1
SMRXD3
SMRXDV/SMCRSDV
SMRXC
GNDD
SMTXER
SMTXD1
SMTXD3
PMRXD0
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
LED2-1
LED2-2
VDDIO
GNDD
LED3-0
101
100
99
98
97
LED2-0
102
103
GNDA
LED1-0
MDIXDIS
TEST2
GNDA
IN_PWR_SEL
LDO_O
NC
X2
X1
NC
SCANEN
TESTEN
VDDC
GNDD
RST_N
PS0
PS1
SPIS_N
SPID/SDA
SPIC/SCL
SPIQ
MDIO
MDC
LED1-1
LED1-2 104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
VDDAR
RXP1
RXM1
GNDA
TXP1
TXM1
VDDAT
RXP2
RXM2
RXM3
TXP3
RXP4
TXM4
VDDAR
RXM5
GNDA
GNDA
TXP2
TXM2
VDDAR
GNDA
ISET
VDDAT
RXP3
GNDA
TXM3
VDDAT
RXM4
GNDA
TXP4
GNDA
RXP5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
NC
LED5-0
128-Pin PQFP Pin Configuration
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
18
Revision-1.1
TXM5
VDDAT
NC
TXP5
33
34
35
36
37
38
KSZ8895ML
(Top View) NC
PMRXDV
NC
NC
NC
NC
NC
NC
PWRDN_N
INTR_N
GNDD
VDDC
PMTXEN
PMTXD3
PMTXD2
PMTXD1
PMTXD0
PMTXER
PMTXC
GNDD
PMRXD1
VDDIO
PMRXC
PMRXD3
PMRXD263
62
61
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
40
39
64
NC
LED3-1
LED4-0
LED3-2
SCONF1
SCOL
SMRXD2
VDDIO
SMTXC
SMTXD0
SMTXD2
SMTXEN
PCOL
PCRS
PMRXER
LED4-1
LED4-2
LED5-1
LED5-2
VDDC
GNDD
SCONF0
SCRS
SMRXD0
SMRXD1
SMRXD3
SMRXDV
SMRXC
GNDD
SMTXER
SMTXD1
SMTXD3
PMRXD0
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
LED2-1
LED2-2
VDDIO
GNDD
LED3-0
101
100
99
98
97
LED2-0 102
103
GNDA
LED1-0
MDIXDIS
TEST2
GNDA
IN_PWR_SEL
LDO_O
NC
X2
X1
NC
SCANEN
TESTEN
VDDC
GNDD
RST_N
PS0
PS1
SPIS_N
SPID/SDA
SPIC/SCL
SPIQ
MDIO
MDC
LED1-1
LED1-2 104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
VDDAR
RXP1
RXM1
GNDA
TXP1
TXM1
VDDAT
RXP2
RXM2
RXM3
TXP3
RXP4
TXM4
VDDAR
RXM5
GNDA
GNDA
TXP2
TXM2
VDDAR
GNDA
ISET
VDDAT
RXP3
GNDA
TXM3
VDDAT
RXM4
GNDA
TXP4
GNDA
RXP5
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
NC
LED5-0
128-Pin LQFP Pin Configuration
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
19
Revision-1.1
Pin Description
Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
1
MDI-XDIS
IPD
1 5
Disable auto MDI/MDI-X.
PD (default) = normal operation.
PU = disable auto MDI/MDI-X on all ports.
2
GNDA
GND
Analog ground.
3
VDDAR
P
1.2V analog VDD.
4
RXP1
I
1
Physical receive signal + (differential).
5
RXM1
I
1
Physical receive signal - (differential).
6
GNDA
GND
Analog ground.
7
TXP1
O
1
Physical transmit signal + (differential).
8
TXM1
O
1
Physical transmit signal - (differential).
9
VDDAT
P
3.3V analog VDD.
10
RXP2
I
2
Physical receive signal + (differential).
11
RXM2
I
2
Physical receive signal - (differential).
12
GNDA
GND
Analog ground.
13
TXP2
O
2
Physical transmit signal + (differential).
14
TXM2
O
2
Physical transmit signal - (differential).
15
VDDAR
P
1.2V analog VDD.
16
GNDA
GND
Analog ground.
17
ISET
Set physical transmit output current. Pull-down with a
12.4kΩ1% resistor.
18
VDDAT
P
3.3V analog VDD.
19
RXP3
I
3
Physical receive signal + (differential).
20
RXM3
I
3
Physical receive signal - (differential).
21
GNDA
GND
Analog ground.
22
TXP3
O
3
Physical transmit signal + (differential).
23
TXM3
O
3
Physical transmit signal – (differential).
24
VDDAT
P
3.3V analog VDD.
25
RXP4
I
4
Physical receive signal + (differential).
26
RXM4
I
4
Physical receive signal - (differential).
27
GNDA
GND
Analog ground.
28
TXP4
O
4
Physical transmit signal + (differential).
29
TXM4
O
4
Physical transmit signal - (differential).
30
GNDA
GND
Analog ground.
31
VDDAR
P
1.2V analog VDD.
32
RXP5
I
5
Physical receive signal + (differential).
33
RXM5
I
5
Physical receive signal - (differential).
34
GNDA
GND
Analog ground.
35
TXP5
O
5
Physical transmit signal + (differential).
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
20
Revision-1.1
Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
36
TXM5
O
5
Physical transmit signal - (differential).
37
VDDAT
P
3.3V analog VDD.
38
NC/FXSD3
IPD
3
FQX: This pin can be floating when port 3 is used as copper port
(default). Port 3 can be set to fiber mode by Register 239 bit [7], this
pin is used for fiber signal detect pin on Port 3 in Fiber mode.
MQX/RQX/ML: no connection.
39
FXSD4
IPD
4
FQX: Fiber signal detect pin for Port 4.
MQX/RQX/ML: no connection.
40
NC
NC
No connection. Leave NC pin floating.
41
NC
NC
No connection. Leave NC pin floating.
42
NC
NC
No connection. Leave NC pin floating.
43
NC
NC
No connection. Leave NC pin floating.
44
NC
NC
No connection. Leave NC pin floating.
45
NC
NC
No connection. Leave NC pin floating.
46
NC
NC
No connection. Leave NC pin floating.
47
PWRDN_N
IPU
Full-chip power down. Active low.
48
INTR_N
OPU
Interrupt. This pin is Open-Drain output pin.
49
GNDD
GND
Digital ground.
50
VDDC
P
1.2V digital core VDD.
51
PMTXEN
IPD
5
PHY [5] MII/RMII transmit enable.
52
PMTXD3
IPD
5
MQX/FQX/ML: PHY [5] MII transmit bit 3.
RQX: no connection for RMII.
53
PMTXD2
IPD
5
MQX/FQX/ML: PHY [5] MII transmit bit 2.
RQX: no connection for RMII.
54
PMTXD1
IPD
5
PHY [5] MII/RMII transmit bit 1.
55
PMTXD0
IPD
5
PHY [5] MII/RMII transmit bit 0.
56
PMTXER
IPD
5
MQX/FQX/ML: PHY [5] MII transmit error. RQX: no connection for
RMII.
57
PMTXC/PMREFCLK
I/O
5
MQX/FQX/ML: Output PHY [5] MII transmit clock
RQX: Input PHY [5] RMII reference clock, 50MHz 50ppm, the
50MHz clock comes from PMRXC Pin 60.
58
GNDD
GND
Digital ground.
59
VDDIO
P
3.3V, 2.5V or 1.8V digital VDD for digital I/O circuitry.
60
PMRXC
I/O
5
MQX/FQX/ML: Output PHY [5] MII receive clock.
RQX: Output PHY [5] RMII reference clock, this clock is used when
opposite doesn’t provide RMII 50MHz clock or the system doesn’t
provide an external 50MHz clock for the P5-RMII interface.
61
PMRXDV/PMCRSDV
IPD/O
5
MQX/FQX/ML: PMRXDV is for PHY [5] MII receive data valid.
RQX: PMCRSDV is for PHY [5] RMII Carrier Sense/Receive Data
Valid Output.
62
PMRXD3
IPD/O
5
MQX/FQX/ML: PHY [5] MII receive bit 3.
RQX: no connection for RMII.
Strap option:
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
21
Revision-1.1
Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
PD (default) = enable flow control.
PU = disable flow control.
63
PMRXD2
IPD/O
5
MQX/FQX/ML: PHY [5] MII receive bit 2.
RQX: no connection for RMII.
Strap option:
PD (default) = disable back pressure.
PU = enable back pressure.
64
PMRXD1
IPD/O
5
PHY [5] MII/RMII receive bit 1.
Strap option:
PD (default) = drop excessive collision packets.
PU = does not drop excessive collision packets.
65
PMRXD0
IPD/O
5
PHY [5] MII/RMII receive bit 0.
Strap option:
PD (default) = disable aggressive back-off algorithm in half-duplex
mode.
PU = enable for performance enhancement.
66
PMRXER
IPD/O
5
MQX/FQX/ML:PHY [5] MII receive error
RQX: no connection for RMII
Strap option:
PD (default) = packet size 1518/1522 bytes.
PU = 1536 bytes.
67
PCRS
IPD/O
5
MQX/FQX/ML: PHY [5] MII carrier sense.
RQX: no connection for RMII.
Strap option for port 4 only.
PD (default) = force half-duplex if auto-negotiation is disabled or
fails.
PU = force full-duplex if auto negotiation is disabled or fails. Refer to
Register 76.
68
PCOL
IPD/O
5
MQX/FQX/ML: PHY [5] MII collision detect.
RQX: no connection.
Strap option for port 4 only.
PD (default) = no force flow control, normal operation.
PU = force flow control. Refer to Register 66.
69
SMTXEN
IPD
Port 5 Switch MII/RMII transmit enable.
70
SMTXD3
IPD
MQX/FQX/ML: Port 5 Switch MII transmit bit 3.
RQX: no connection for RMII.
71
SMTXD2
IPD
MQX/FQX/ML: Port 5 Switch MII transmit bit 2.
RQX: no connection for RMII.
72
SMTXD1
IPD
Port 5 Switch MII/RMII transmit bit 1.
73
SMTXD0
IPD
Port 5 Switch MII/RMII transmit bit 0.
74
SMTXER
IPD
MQX/FQX/ML: Port 5 Switch MII transmit error.
RQX: no connection for RMII.
75
SMTXC/SMREFCLK
I/O
MQX/FQX/ML: Port 5 Switch MII transmit clock,
Input: SW5-MII MAC mode, Output: SW5-MII PHY modes.
RQX: Input SW5-RMII 50MHz +/-50ppm reference clock. The
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
22
Revision-1.1
Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
50MHz clock comes from SMRXC Pin 78 when the device is the
clock mode which the device’s clock comes from 25MHz
crystal/oscillator from pins X1/X2. Or the 50MHz clock comes from
external 50MHz clock source when the device is the normal mode
which the device’s clock source comes from SMTXC pin not from
X1/X2 pins.
76
GNDD
GND
Digital ground.
77
VDDIO
P
3.3V, 2.5V or 1.8V digital VDD for digital I/O circuitry.
78
SMRXC
I/O
MQX/FQX/ML: Port 5 Switch MII receive clock,
Input: SW5-MII MAC mode, Output: SW5-MII PHY mode.
RQX: Output SW5-RMII 50MHz clock, this clock is used when
opposite doesn’t provide RMII reference clock or the system doesn’t
provide an external 50MHz clock for the RMII interface.
79
SMRXDV/SMCRSDV
IPD/O
MQX/FQX/ML: SMRXDV is for Switch MAC5 MII receive data valid.
RQX: SMCRSDV is for MAC5 RMII Carrier Sense/Receive Data
Valid Output.
80
SMRXD3
IPD/O
MQX/FQX/ML: Port 5 Switch MII receive bit 3.
RQX: no connection for RMII
Strap option:
PD (default) = Disable Switch SW5-MII full-duplex flow control
PU = Enable Switch SW5-MII full-duplex flow control.
81
SMRXD2
IPD/O
MQX/FQX/ML: Port 5 Switch MII receive bit 2.
RQX: no connection for RMII
Strap option:
PD (default) = Switch SW5-MII in full-duplex mode;
PU = Switch SW5-MII in half-duplex mode.
82
SMRXD1
IPD/O
Port 5 Switch MII/RMII receive bit 1.
Strap option:
PD (default) = Port 5 Switch SW5-MII in 100Mbps mode.
PU = Switch SW5-MII in 10Mbps mode.
83
SMRXD0
IPD/O
Port 5 Switch MII/RMII receive bit 0.
Strap option:
LED mode
PD (default) = mode 0; PU = mode 1. See “Register 11.”
Mode 0, link at:
100/Full LEDx[2,1,0] = 0, 0, 0
100/Half LEDx[2,1,0] = 0, 1, 0
10/Full LEDx[2,1,0] = 0, 0, 1
10/Half LEDx[2,1,0] = 0, 1, 1
Mode 1, link at:
100/Full LEDx[2,1,0] = 0, 1, 0
100/Half LEDx[2,1,0] = 0, 1, 1
10/Full LEDx[2,1,0] = 1, 0, 0
10/Half LEDx[2,1,0] = 1, 0, 1
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Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
Mode 0
Mode 1
LEDX_2
Lnk/Act
100Lnk/Act
LEDX_1
Fulld/Col
10Lnk/Act
LEDX_0
Speed
Full duplex
84
SCOL
IPD/O
MQX/FQX/ML: Port switch MII collision detect,
Input: SW5-MII MAC modes, Output: SW5-MII PHY modes
RQX: no connection for RMII
85
SCRS
IPD/O
MQX/FQX/ML: Port switch MII collision detect,
Input: SW5-MII MAC modes, Output: SW5-MII PHY modes
RQX: no connection for RMII
86
SCONF1
IPD
Pins 91, 86, and 87 are dual MII/RMII configuration pins for the Port
5 MAC5 MII/RMII and PHY [5] MII/RMII. SW5-MII supports both
MAC mode and PHY modes. P5-MII supports PHY mode only. See
pins configuration below:
Pin# (91, 86, 87)
Port 5 Switch
MAC5 SW5-
MII/RMII
Port5 PHY5
P5- MII/RMII
000
Disable, Otri
Disable, Otri
001
PHY Mode MII, or
RMII
Disable, Otri
010
MAC Mode MII, or
RMII
Disable, Otri
011
PHY Mode SNI
Disable, Otri
100
Disable (default)
Disable (default)
101
PHY Mode MII or
RMII
P5-MII/RMII
110
MAC Mode MII or
RMII
P5-MII/RMII
111
PHY Mode SNI
P5- MII/RMII
87
SCONF0
IPD
Dual MII/RMII configuration pin. See pin 86 descriptions.
88
GNDD
GND
Digital ground.
89
VDDC
P
1.2V digital core VDD.
90
LED5-2
IPU/O
5
LED indicator 2.
Strap option:
Aging setup. See “Aging” section.
PU (default) = aging enable
PD = aging disable.
91
LED5-1
IPU/O
5
LED indicator 1.
Strap option:
PU (default): enable PHY [5] MII I/F.
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Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
PD: tri-state all PHY [5] MII output. See “Pin 86 SCONF1.”
92
LED5-0
IPU/O
5
LED indicator 0.
Strap option for port 4 only.
PU (default) = Enable auto-negotiation.
PD = Disable auto-negotiation. Strap to Register76 bit [7].
93
LED4-2
IPU/O
4
LED indicator 2.
94
LED4-1
IPU/O
4
LED indicator 1.
95
LED4-0
IPU/O
4
LED indicator 0.
Strap option:
PU (default) = Normal mode.
PD = Energy Detection mode (EDPD mode)
Strap to Register 14 bits [4:3]
96
LED3-2
IPU/O
3
LED indicator 2.
97
LED3-1
IPU/O
3
LED indicator 1.
98
LED3-0
IPU/O
3
LED indicator 0.
Strap option:
PU (default) = Select I/O drive strength (8mA);
PD = Select I/O drive strength (12mA).
Strap to Register132 bit [7-6].
99
GNDD
GND
Digital ground.
100
VDDIO
P
3.3V, 2.5V or 1.8V digital VDD for digital I/O circuitry.
101
LED2-2
IPU/O
2
LED indicator 2.
Strap option for RQX only:
PU (default) = Select the device as clock mode in SW5- RMII,
25MHz crystal/oscillator to X1/X2 pins of the device and pins of
SMRXC and PMRXC output 50MHz clock.
PD = Select the device as normal mode in SW5-RMII. Switch MAC5
used only. The input clock from X1/X2 pins is not used, the device’s
clock source comes from SMTXC/SMREFCLK pin which the 50MHz
reference clock comes from external 50MHz clock source, PMRXC
can output 50MHz clock for P5-RMII interface in the normal mode.
102
LED2-1
IPU/O
2
LED indicator 1.
Strap option: for Port 3 only.
PU (default) = Enable auto-negotiation.
PD = Disable auto-negatiation. Strap to Register60 bit [7].
103
LED2-0
IPU/O
2
LED indicator 0.
104
LED1-2
IPU/O
1
LED indicator 2.
105
LED1-1
IPU/O
1
LED indicator 1.
Strap option: for port 3 only.
PU (default) = no force flow control, normal operation.
PD = force flow control. Strap to Register60 bit [4].
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Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
106
LED1-0
IPU/O
1
LED indicator 0.
Strap option for port 3 only.
PU (default) = force half-duplex if auto-negotiation is disabled or
fails.
PD = force full-duplex if auto negotiation is disabled or fails.
Strap to Register60 bit [5].
107
MDC
IPU
All
Switch or PHY [5] MII management (MIIM registers) data clock. Or
SMI interface clock
108
MDIO
IPU/O
All
Switch or PHY [5] MII management (MIIM registers) data I/O. Or
SMI interface data I/O.
Features internal pull down to define pin state when not driven.
Note: Need an external pull-up when driven.
109
SPIQ
IPU/O
All
SPI serial data output in SPI slave mode.
Note: Need an external pull-up when driven.
110
SPIC/SCL
IPU/O
All
(1) Input clock up to 25MHz in SPI slave mode,
(2) output clock at 61kHz in I2C master mode. See “Pin 113.”
Note: Need an external pull-up when driven.
111
SSPID/SDA
IPU/O
All
(1) Serial data input in SPI slave mode;
(2) serial data input/output in I2C master mode. See “Pin 113.”
Note: Need an external pull-up when driven.
112
SPIS_N
IPU
All
Active low.
(1) SPI data transfer start in SPI slave mode. When SPIS_N is high,
the KSZ8895MQX/RQX/FQX/ML is deselected and SPIQ is held in
high impedance state, a high-to-low transition to initiate the SPI data
transfer.
(2) not used in I2C master mode.
113
PS1
IPD
Serial bus configuration pin.
For this case, if the EEPROM is not present, the
KSZ8895MQX/RQX/FQX/ML will start itself with the PS[1.0] = 00
default register values.
Pin Configuration
Serial Bus Configuration
PS[1.0] = 00
I2C Master Mode for EEPROM
PS[1.0] = 01
SMI Interface Mode
PS[1.0] = 10
SPI Slave Mode for CPU Interface
PS[1.0] = 11
Factory Test Mode (BIST)
114
PS0
IPD
Serial bus configuration pin. See “Pin 113.”
115
RST_N
IPU
Reset the KSZ8895MQX/RQX/FQX/ML device. Active low.
116
GNDD
GND
Digital ground.
117
VDDC
P
1.2V digital core VDD.
118
TESTEN
IPD
NC for normal operation. Factory test pin.
119
SCANEN
IPD
NC for normal operation. Factory test pin.
120
NC
NC
No connection. Leave NC pin floating.
121
X1
I
25MHz crystal clock connection/or 3.3V Oscillator input.
Crystal/Oscillator should be ±50ppm tolerance.
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Pin
Number
Pin Name
Type(1)
Port
Pin Function(2)
122
X2
O
25MHz crystal clock connection.
123
NC
NC
No connection. Leave NC pin floating.
124
NC
NC
No connection. Leave NC pin floating.
125
LDO_O
P
LDO_O pin connect to gate pin of MOSFET if using the internal 1.2V
LDO controller.
LDO_O pin will be floating if using an external 1.2V LDO.
Note: When pin126 voltage is greater than the internal 1.2V LDO
controller enable threshold (1V), the internal 1.2V LDO controller is
enabled and creates a 1.2V output when using an external
MOSFET.
When pin126 is pull-down, the internal 1.2V LDO controller is
disabled and pin 125 tri-stated.
126
IN_PWR_SEL
I
Pull-up or a resistor divider: Enable internal 1.2V LDO controller.
Pull-down: Disable internal 1.2V LDO controller.
Note: A 4k pull-up and a 2k pull-down resistors divider network is
recommended if using the internal 1.2V LDO controller and an
external MOSFET for 1.2V power.
A 100Ω (approximately) resistor between the source and drain pins
on the MOSFET is highly recommended as well.
You can also use an external 1.2V LDO for 1.2V power supply.
127
GNDA
GND
Analog ground.
128
TEST2
NC
NC for normal operation. Factory test pin.
Notes:
2. P = Power supply.
I = Input.
O = Output.
I/O = Bidirectional.
GND = Ground.
IPU = Input w/internal pull-up.
IPD = Input w/internal pull-down.
IPD/O = Input w/internal pull-down during reset, output pin otherwise.
OTRI = Output tristated.
3. NC = Do not connect to PCB.
PU = Strap pin pull-up.
PD = Strap pull-down.
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Pin for Strap-in Options
The KSZ8895MQX/RQX/FQX/ML can function as a managed switch or an unmanaged switch. If no EEPROM or
micro-controller exists, then the KSZ8895MQX/RQX/FQX/ML will operate from its default setting. The strap-in option
pins can be configured by external pull-up/down resistors and take effect after power down reset or warm reset. The
functions are described in the table below.
Pin #
Pin Name
PU/PD(1)
Description(2)
1
MDI-XDIS
IPD
Disable auto MDI/MDI-X.
Strap option:
PD = (default) = normal operation.
PU = disable auto MDI/MDI-X on all ports.
62
PMRXD3
IPD/O
PHY [5] MII receive bit 3.
Strap option:
PD (default) = enable flow control;
PU = disable flow control.
63
PMRXD2
IPD/O
PHY [5] MII receive bit 2.
Strap option:
PD (default) = disable back pressure;
PU = enable back pressure.
64
PMRXD1
IPD/O
PHY [5] MII receive bit 1.
Strap option:
PD (default) = drop excessive collision packets;
PU = does not drop excessive collision packets.
65
PMRXD0
IPD/O
PHY [5] MII receive bit 0.
Strap option:
PD (default) = disable aggressive back-off algorithm in half-duplex mode;
PU = enable for performance enhancement.
66
PMRXER
IPD/O
PHY [5] MII receive error.
Strap option:
PD (default) = 1522/1518 bytes;
PU = packet size up to 1536 bytes.
67
PCRS
IPD/O
PHY [5] MII carrier sense
Strap option for Port 4 only.
PD (default) = force half-duplex if auto-negotiation is disabled or fails.
PU = force full-duplex if auto-negotiation is disabled or fails. Refer to Register
76.
68
PCOL
IPD/O
PHY [5] MII collision detect
Strap option for Port 4 only.
PD (default) = no force flow control.
PU = force flow control. Refer to Register 66.
80
SMRXD3
IPD/O
Switch MII receive bit 3.
Strap option:
PD (default) = disable switch SW5-MII full-duplex flow control;
PU = enable switch SW5-MII full-duplex flow control.
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Pin #
Pin Name
PU/PD(1)
Description(2)
81
SMRXD2
IPD/O
Switch MII receive bit 2.
Strap option:
PD (default) = switch SW5-MII in full-duplex mode;
PU = switch SW5-MII in half-duplex mode.
82
SMRXD1
IPD/O
Switch MII receive bit 1.
Strap option:
PD (default) = switch SW5-MII in 100Mbps mode.
PU = switch MII in 10Mbps mode.
83
SMRXD0
IPD/O
Switch MII receive bit 0.
Strap option: LED mode PD (default) = mode 0; PU = mode 1. See “Register
11.”
Mode 0
Mode 1
LEDX_2
Lnk/Act
100Lnk/Act
LEDX_1
Fulld/Col
10Lnk/Act
LEDX_0
Speed
Fulld
86
SCONF1
IPD
Pin 91,86,87 are dual MII/RMII configuration pins for the Port 5 MAC 5 MII/RMII
and PHY [5] MII/RMII. SW5-MII supports both MAC mode and PHY modes. P5-
MII supports PHY mode only. See pins configuration below.
Pins [91, 86, 87]
Port 5 Switch MAC5
SW5- MII/RMII
Port5 PHY5
P5- MII/RMII
000
Disable, Otri
Disable, Otri
001
PHY Mode MII, or RMII
Disable, Otri
010
MAC Mode MII, or RMII
Disable, Otri
011
PHY Mode SNI
Disable, Otri
100
Disable (default)
Disable (default)
101
PHY Mode MII or RMII
P5-MII/RMII
110
MAC Mode MII or RMII
P5-MII/RMII
111
PHY Mode SNI
P5- MII/RMII
87
SCONF0
IPD
Dual MII/RMII configuration pin. See pin 86 description.
90
LED5-2
IPU/O
LED5 indicator 2.
Strap option: Aging setup. See “Aging” section
PU (default) = aging enable;
PD = aging disable.
91
LED5-1
IPU/O
LED5 indicator 1.
Strap option:
PU (default): enable PHY [5] MII I/F.
PD: tri-state all PHY [5] MII output. See “Pin 86 SCONF1.”
92
LED5-0
IPU/O
LED5 indicator 0.
Strap option for Port 4 only.
PU (default) = Enable auto-negotiation.
PD = Disable auto-negotiation. Strap to Register76 bit [7].
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Pin #
Pin Name
PU/PD(1)
Description(2)
95
LED4-0
IPU/O
LED indicator 0.
Strap option:
PU (default) = Normal mode.
PD = Energy Detection mode (EDPD mode).
Strap to Register 14 bits [4:3].
98
LED3-0
IPU/O
LED3 indicator 0.
Strap option:
PU (default) = Select I/O current drive strength (8mA);
PD = Select I/O current drive strength (12mA).
Strap to Register132 bit [7:6].
101
LED2-2
IPU/O
LED2 indicator 2.
Strap option for KSZ8895RQX only:
PU (default) = Select the device as clock mode in RQX SW5- RMII, 25MHz
crystal to X1/X2 pins of the device and REFCLK output 50MHz clock.
PD = Select the device as normal mode in SW5-RMII. Switch MAC5 used only.
The input clock is useless from X1/X2 pin, the device’s clock comes from
SMTXC/SMREFCLK pin, 50MHz reference clock from external 50MHz clock
source.
102
LED2-1
IPU/O
LED2 indicator 1.
Strap option for Port 3 only.
PU (default) = Enable auto-negotiation.
PD = Disable auto-negotiation.
Strap to Register60 bit [7].
105
LED1-1
IPU/O
LED1 indicator 1.
Strap option for Port 3 only.
PU (default) = no force flow control, normal operation.
PD = force flow control. Strap to Register50 bit [4].
106
LED1-0
IPU/O
LED1 indicator 0.
Strap option for Port 3 only.
PU (default) = force half-duplex if auto-negotiation is disabled or fails.
PD = force full-duplex if auto negotiation is disabled or fails.
Strap to Register60 bit [5].
113
PS1
IPD
Serial bus configuration pin. For this case, if the EEPROM is not present, the
KSZ8895MQX/RQX/FQX/ML will start itself with the PS[1:0] = 00 default
register values .
Pin Configuration
Serial Bus Configuration
PS[1:0] = 00
I2C Master Mode for EEPROM
PS[1:0] = 01
SMI Interface Mode
PS[1:0] = 10
SPI Slave Mode for CPU Interface
PS[1:0] = 11
Factory Test Mode (BIST)
114
PS0
IPD
Serial bus configuration pin. See “Pin 113.”
128
TEST2
NC
NC for normal operation. Factory test pin.
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Notes:
4. NC = No connect.
IPD = Input w/internal pull-down.
IPD/O = Input w/internal pull-down during reset, output pin otherwise.
IPU/O = Input w/internal pull-up during reset, output pin otherwise.
5. NC = Do not connect to PCB.
PD = Strap pin pull-down.
PU = Strap pin pull-up.
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Introduction
The KSZ8895MQX/RQX/FQX/ML contains five 10/100 physical layer transceivers and five media access control
(MAC) units with an integrated Layer 2 managed switch. The device runs in three modes. The first mode is as a five-
port integrated switch. The second is as a five-port switch with the fifth port decoupled from the physical port. In this
mode, access to the fifth MAC is provided through a media independent interface (MII/RMII). This is useful for
implementing an integrated broadband router. The third mode uses the dual MII/RMII feature to recover the use of
the fifth PHY. This allows the additional broadband gateway configuration, where the fifth PHY may be accessed
through the P5-MII/RMII port.
The KSZ8895MQX/RQX/FQX/ML has the flexibility to reside in a managed or unmanaged design. In a managed
design, a host processor has complete control of the KSZ8895MQX/RQX/FQX/ML via the SPI bus, or the
MDC/MDIO interface. An unmanaged design is achieved through I/O strapping or EEPROM programming at system
reset time.
On the media side, the KSZ8895MQX/RQX/FQX/ML supports IEEE 802.3 10BASE-T, 100BASE-TX on all copper
ports with Auto MDI/MDIX. The KSZ8895FQX supports 100BASE-FX on port 4, and port 3 is configurable either
copper as default or fiber. The KSZ8895MQX/RQX/FQX/ML can be used as a fully managed five-port switch or
hooked up to a microprocessor by its SW-MII/RMII interfaces for any application solutions.
Physical signal transmission and reception are enhanced through the use of patented analog circuitry and DSP
technology that make the design more efficient and allows for reduced power consumption and strong electrical
noise immunity.
Major enhancements from the KS8995MQ/RQ/FMQ to the KSZ8895MQX/RQX/FQX include more saving power,
there is no a limitation for the center taps of the transformer in KSZ8895MQX/RQX/FQX, KSZ8895MQ/RQ/FMQ
request the center taps of RX an TX of the transformer not to be tied together for saving power, except using 0.11um
process and add Micrel LinkMD feature in KSZ8895MQX/RQX/FQX switches. The KSZ8895MQX/RQX/FQX are
complete compatible with KSZ8895MQ/RQ/FMQ.
Functional Overview: Physical Layer Transceiver
100BASE-TX Transmit
The 100BASE-TX transmit function performs parallel-to-serial conversion, 4B/5B coding, scrambling, NRZ-to-NRZI
conversion, MLT3 encoding and transmission. The circuit starts with a parallel-to-serial conversion, which converts
the MII data from the MAC into a 125MHz serial bit stream. The data and control stream is then converted into 4B/5B
coding followed by a scrambler. The serialized data is further converted from NRZ-to-NRZI format, and then
transmitted in MLT3 current output. The output current is set by an external 1% 12.4kΩ resistor for the 1:1
transformer ratio. It has a typical rise/fall time of 4ns and complies with the ANSI TP-PMD standard regarding
amplitude balance, overshoot, and timing jitter. The wave-shaped 10BASE-T output is also incorporated into the
100BASE-TX transmitter.
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, descrambling, 4B/5B decoding, and serial-to-parallel conversion. The
receiving side starts with the equalization filter to compensate for intersymbol interference (ISI) over the twisted pair
cable. Since the amplitude loss and phase distortion is a function of the length of the cable, the equalizer has to
adjust its characteristics to optimize the performance. In this design, the variable equalizer will make an initial
estimation based on comparisons of incoming signal strength against some known cable characteristics, then tunes
itself for optimization. This is an ongoing process and can self-adjust against environmental changes such as
temperature variations.
The equalized signal then goes through a DC restoration and data conversion block. The DC restoration circuit is
used to compensate for the effect of baseline wander and improve the dynamic range. The differential data
conversion circuit converts the MLT3 format back to NRZI. The slicing threshold is also adaptive.
The clock recovery circuit extracts the 125MHz clock from the edges of the NRZI signal. This recovered clock is then
used to convert the NRZI signal into the NRZ format. The signal is then sent through the de-scrambler followed by
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the 4B/5B decoder. Finally, the NRZ serial data is converted to the MII format and provided as the input data to the
MAC.
PLL Clock Synthesizer
The KSZ8895MQX/RQX/FQX/ML generates 125MHz, 83MHz, 41MHz, 25MHz and 10MHz clocks for system timing.
Internal clocks are generated from an external 25MHz crystal or oscillator.
Scrambler/Descrambler (100BASE-TX only)
The purpose of the scrambler is to spread the power spectrum of the signal in order to reduce EMI and baseline
wander. The data is scrambled through the use of an 11-bit wide linear feedback shift register (LFSR). This can
generate a 2047-bit non-repetitive sequence. The receiver will then descramble the incoming data stream with the
same sequence at the transmitter.
100BASE-FX Operation
100BASE-FX operation is very similar to 100BASE-TX operation except that the scrambler/descrambler and MLT3
encoder/decoder are bypassed on transmission and reception. In this mode, the auto-negotiation feature is bypassed
since there is no standard that supports fiber auto-negotiation.
100BASE-FX Signal Detection
The physical port runs in 100BASE-FX fiber mode for the Port 3 and Port 4 of the KSZ8895FQX. This signal is
internally referenced to 1.2V. The fiber module interface should be set by a voltage divider such that FXSDx ‘H’ is
above this 1.2V reference, indicating signal detect, and FXSDx ‘L’ is below the 1.2V reference to indicate no signal.
There is no auto-negotiation for 100BASE-FX mode, the ports must be forced to either full or half-duplex for the fiber
ports. Note that strap-in options support Port 3 and Port 4 to disable auto-negotiation, force 100Base-FX speed, force
duplex mode, and force flow control for KSZ8895FQX with unmanaged mode.
100BASE-FX Far End Fault
Far end fault occurs when the signal detection is logically false from the receive fiber module. When this occurs, the
transmission side signals the other end of the link by sending 84 1s followed by a zero in the idle period between
frames. The far end fault may be disabled through register settings.
10BASE-T Transmit
The output 10BASE-T driver is incorporated into the 100BASE-T driver to allow transmission with the same
magnetics. They are internally wave-shaped and pre-emphasized into outputs with a typical 2.3V amplitude. The
harmonic contents are at least 27dB below the fundamental when driven by an all-ones Manchester-encoded signal.
10BASE-T Receive
On the receive side, input buffer and level detecting squelch circuits are employed. A differential input receiver circuit
and a PLL perform the decoding function. The Manchester-encoded data stream is separated into clock signal and
NRZ data. A squelch circuit rejects signals with levels less than 400mV or with short pulsewidths in order to prevent
noises at the RXP or RXM input from falsely triggering the decoder. When the input exceeds the squelch limit, the
PLL locks onto the incoming signal and the KSZ8895MQX/RQX/FQX/ML decodes 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 KSZ8895MQX/RQX/FQX/ML 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-sense function detects remote transmit and receive pairs and correctly assigns transmit and receive pairs
for the KSZ8895MQX/RQX/FQX/ML device. This feature is extremely useful when end users are unaware of cable
types, and also, saves on an additional uplink configuration connection. The auto-crossover feature can be disabled
through the port control registers, or MIIM PHY registers. The IEEE 802.3u standard MDI and MDI-X definitions are:
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Table 1. MDI/MDI-X Pin Definitions
MDI
MDI-X
RJ-45 Pins
Signals
RJ-45 Pins
Signals
1
TD+
1
RD+
2
TD-
2
RD-
3
RD+
3
TD+
6
RD-
6
TD-
Straight Cable
A straight cable connects an MDI device to an MDI-X device, or an MDI-X device to an MDI device. The following
diagram depicts a typical straight cable connection between a NIC card (MDI) and a switch, or hub (MDI-X).
Figure 5. Typical Straight Cable Connection
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Crossover Cable
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 switches or hubs (two MDI-X devices).
Figure 6. Typical Crossover Cable Connection
Auto-Negotiation
The KSZ8895MQX/RQX/FQX/ML conforms to the auto-negotiation protocol as described by the 802.3 committee.
Auto-negotiation allows unshielded twisted pair (UTP) link partners to select the highest common mode of operation.
Link partners advertise their capabilities to each other, and then compare their own capabilities with those they
received from their link partners. The highest speed and duplex setting that is common to the two link partners is
selected as the mode of operation. Auto-negotiation is supported for the copper ports only.
The following list shows the speed and duplex operation mode from highest to lowest.
Highest: 100Base-TX, full-duplex
High: 100Base-TX, half-duplex
Low: 10Base-T, full-duplex
Lowest: 10Base-T, half-duplex
If auto-negotiation is not supported or the KSZ8895MQX/RQX/FQX/ML link partner is forced to bypass auto-
negotiation, the KSZ8895MQX/RQX/FQX/ML sets its operating mode by observing the signal at its receiver. This is
known as parallel detection, and allows the KSZ8895MQX/RQX/FQX/ML to establish link by listening for a fixed
signal protocol in the absence of auto-negotiation advertisement protocol. The auto-negotiation link up process is
shown in the following flow chart.
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Figure 7. Auto-Negotiation
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LinkMD® Cable Diagnostics
The LinkMD® feature utilizes 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 maximum distance of 200m and accuracy of ±2m. Internal circuitry displays the TDR information in a user-
readable digital format.
Note: Cable diagnostics are only valid for copper connections and do not support fiber optic operation.
Access
LinkMD® is initiated by accessing the PHY special control/status Registers {26, 42, 58, 74, 90} and the LinkMD result
Registers {27, 43, 59, 75, 91} for ports 1, 2, 3, 4 and 5 respectively; and in conjunction with the Registers Port
Control 12 and 13 for ports 1, 2, 3, 4 and 5 respectively to disable Auto-Negotiation and Auto MDI/MDIX.
Alternatively, the MIIM PHY Registers 0 and 1d can be used for LinkMD® access also.
Usage
The following is a sample procedure for using LinkMD® with Registers {26, 27, 28, 29} on port 1.
1. Disable Auto-Negotiation by writing a ‘1’ to Register 28 (0x1c), bit [7].
2. Disable auto MDI/MDI-X by writing a ‘1’ to Register 29 (0x1d), bit [2] to enable manual control over the differential
pair used to transmit the LinkMD® pulse.
3. A software sequence set up to the internal registers for LinkMD only, see an example below.
4. Start cable diagnostic test by writing a ‘1’ to Register 26 (0x1a), bit [4]. This enable bit is self-clearing.
5. Wait (poll) for Register 26 (0x1a), bit [4] to return a ‘0’, and indicating cable diagnostic test is completed.
6. Read cable diagnostic test results in Register 26 (0x1a), bits [6:5]. The results are as follows:
00 = normal condition (valid test)
01 = open condition detected in cable (valid test)
10 = short condition detected in cable (valid test)
11 = cable diagnostic test failed (invalid test)
The ‘11’ case, invalid test, occurs when the KSZ8895 is unable to shut down the link partner. In this instance, the
test is not run, since it would be impossible for the KSZ8895 to determine if the detected signal is a reflection of
the signal generated or a signal from another source.
7. Get distance to fault by concatenating Register 26 (0x1a), bit [0] and Register 27 (0x1b), bits [7:0]; and
multiplying the result by a constant of 0.4. The distance to the cable fault can be determined by the following
formula:
D (distance to cable fault) = 0.4 x { (Register 26, bit [0]),(Register 27, bits [7:0]) }
D (distance to cable fault) is expressed in meters.
Concatenated value of Registers 26 bit [0] and 27 bit [7:0] should be converted to decimal before decrease 26
and multiplying by 0.4.
The constant (0.4) may be calibrated for different cabling conditions, including cables with a velocity of
propagation that varies significantly from the norm.
For port 2, 3, 4, 5 and for the MIIM PHY registers, LinkMD® usage is similar.
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A LinkMD example
The following is a sample procedure for using LinkMD® on port 1.
//Set Force 100/Full and Force MDIX mode
//W is WRITE the register. R is READ register
W 1c ff
W 1d 04
//Set Internal Registers Temporary Adjustment for LinkMD
W 47 b0
W 27 00
W 37 03 (03- port 1, 04-port2, 05-port3, 06-port4, 07-port5)
W 47 80 (bit7-port1, bit6-port2, bit5-port3, bit4-port4, bit3-port5)
W 27 00
W 37 00
//Enable LinkMD Testing with Fault Cable for port 1
W 1a 10
R 1a
R 1b
//Result analysis based on the values of the Register 0x1a and 0x1b for port 1:
//The Register 0x1a bits [6-5] are for the open or the short detection.
//The Register 0x1a bit [0] + the Register 0x1b bits [7-0] = Vct_Fault [8-0]
//The distance to fault is about 0.4 x {Vct_Fault [8-0] – 26}
Note:
After end the testing, set all registers above to their default value, the default values are ‘00’ for the Register (0x37) and the Register (0x47)
On-chip Termination Resistors
The KSZ8895MQX/RQX/FQX/ML reduces the board cost and simplifies the board layout by using on-chip
termination resistors for all ports and RX/TX differential pairs without the external termination resistors. The
combination of the on-chip termination and internal biasing will save power consumption as compared to using
external biasing and termination resistors, and the transformer will not consume power any more. The center tap of
the transformer does not need to be tied to the analog power and does not tie the center taps together between RX
and TX pairs for its application.
Internal 1.2V LDO Controller
The KSZ8895MQX/RQX/FQX/ML reduces board cost and simplifies board layout by integrating an internal 1.2V LDO
controller to drive a low cost MOSFET to supply the 1.2V core power voltage for a single 3.3V power supply solution.
The internal 1.2V LDO controller can be disabled by pin 126 IN_PWR_SEL pull-down in order to use an external
1.2V LDO.
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Functional Overview: Power
The KSZ8895 device has two options for the power circuit in the design. one is a single 3.3V supply with 3.3V I/O
power by using internal 1.2V LDO controller and one MOSFET for 1.2V analog and digital power. Another one is
using external 1.2V LDO and provide 1.2V power for 1.2V analog and digital power. Table below illustrates the
various voltage options and requirements of the device.
Table 2. Voltages and Power Pins
Power Signal
Name
Device Pins
Requirement
VDDAT
9,18,24,37
3.3V analog power to the transceiver of the device.
VDDIO
59,77,100
Choice of 1.8V or 2.5V or 3.3V for the I/O circuits. These input power pins
power the I/O circuitry of the device.
VDDAR
3, 15, 31
Filtered 1.2V analog voltage. This is where filtered 1.2V is fed back into the
device to power the Analog block.
VDDC
50,89,117
Filtered 1.2V digital voltage. This pin feeds 1.2V to digital circuits within the
Analog block.
GNDA
2,6,12,16,21,27,30,34,127
Analog Ground.
GNDD
49,58,76,88,99,116
Digital Ground.
Using Internal 1.2V LDO Controller
The preferred method of using the internal 1.2V LDO controller with an external MOSFET is illustrated in the figure
below. The number of capacitors, ferrite beads (FB), values of capacitors, and exact placement of components will
depend on the specific design. The 1.2V rail from the drain pin of the MOSFET to VDDAR pin 3 is the 1.2V LDO
feedback path. This connection should be as short as possible and there should be no series components on this
feedback path. When the voltage of pin 126 is just over 1V along with the 3.3V power-up, that will enable the internal
1.2V LDO controller. The 1.2V LDO regulator (internal 1.2V LDO controller plus an external MOSFET) requests
about 3.0V voltage at the ‘S’ pin of MOSFET when the internal 1.2V LDO controller is just enabled, the resistor
divider will meet this requirement.
FB
125
VDDAT
9,18,24,37
3,15,31
3.3V 1.2V
126 VDDAR
VDDC 50,89,117
VDDIO
59,77,100
GNDA
GNDD
2,6,12,16,21,27,30,34,127 49,58,76,88,99,116
4K
2K
DS
G
100ohm
Figure 8. Recommended 1.2V Power Connection using Internal 1.2V LDO Controller
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Using External 1.2V LDO Regulator
The KSZ8895MQX/RQX/FQX/ML can use an external 1.2V LDO regulator too. When use an external 1.2V LDO
regulator solution, the pin 126 should be pulled down by the pull-down resistor to disable the internal 1.2V LDO
controller. There is no a power sequence request if all power rails voltage are ready after the power-up reset done.
Using the external 1.2V LDO regulator is illustrated in Figure below. The number of capacitors, values of capacitors,
and exact placement of components will depend on the specific design.
FB
125
VDDAT
9,18,24,37
3,15,31
126 VDDAR
VDDC 50,89,117
VDDIO
59,77,100
GNDA
GNDD
2,6,12,16,21,27,30,34,127 49,58,76,88,99,116
1K
1.2V
Figure 9. Recommended 1.2V Power Connection Using the External 1.2V Regulator
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Functional Overview: Power Management
The KSZ8895MQX/RQX/FQX/ML supports a full chip hardware power down mode. When the PWRDN pin 47 is
internally activated low (pin PWRDN = 0), the entire chip is powered down. If this pin is de-asserted, the chip will be
reset internally.
The KSZ8895MQX/RQX/FQX/ML can also use multiple power levels of 3.3V, 2.5V or 1.8V for VDDIO to support
different I/O voltage.
The KSZ8895MQX/RQX/FQX/ML supports enhanced power management in a low power state, with energy
detection to ensure low power dissipation during device idle periods. There are five operation modes under the
power management function which are controlled by the Register 14 bit [4:3] and the Port Register Control 13 bit 3
as shown below:
Register 14 bits [4:3] = 00 Normal Operation Mode
Register 14 bits [4:3] = 01 Energy Detect Mode
Register 14 bits [4:3] = 10 Soft Power Down Mode
Register 14 bits [4:3] = 11 Power Saving Mode
The Port Register 29, 45, 61, 77, 93 Control 13 bit3 = 1 are for the Port Based Power-Down Mode.
Table 2 indicates all internal function blocks’ status under four different power management operation modes.
Table 3. Internal Function Block Status
KSZ8895MQX/RQX/FQX/ML
Function Blocks
Power Management Operation Modes
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
Normal Operation Mode
This is the default setting bits [4:3] = 00 in Register 14 after chip power-up or hardware reset. When
KSZ8895MQX/RQX/FQX/ML is in 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 normal operation mode, the host CPU can set the bits [4:3] in Register 14 to change the current normal
operation mode to any one of the other three power management operation modes.
Energy Detect Mode
Energy detect mode provides a mechanism to save more power than in the normal operation mode when the
KSZ8895MQX/RQX/FQX/ML port is not connected to an active link partner. In this mode, the device will save more
power when the cables are unplugged. If the cable is not plugged in, the device can automatically enter a low power
state—the energy detect mode. In this mode, the device will keep transmitting 120ns width pulses at 1 pulse/s rate.
Once activity resumes due to plugging a cable in or attempting by the far end to establish link, the device can
automatically 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
device reduces power consumption by disabling all circuitry except the energy detect circuitry of the receiver. The
energy detect mode is entered by setting bits [4:3] = 01 in Register 14. When the KSZ8895MQX/RQX/FQX/ML is in
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this mode, it will monitor the cable energy. If there is no energy on the cable for a time longer than the pre-configured
value at bit [7:0] Go-Sleep time in Register 15, the device will go into low power state. When
KSZ8895MQX/RQX/FQX/ML is in low power state, it will keep monitoring the cable energy. Once the energy is
detected from the cable, the device will enter normal power state. When the device is at normal power state, it is able
to transmit or receive packet from the cable.
Soft Power Down Mode
The soft power down mode is entered by setting bits [4:3] = 10 in Register 14. When KSZ8895MQX/RQX/FQX/ML is
in this mode, all PLL clocks are disabled, also all of PHYs and the MACs are off. Any dummy host access will wake-
up this device from current soft power down mode to normal operation mode and internal reset will be issued to
make all internal registers go to the default values.
Power Saving Mode
The power saving mode is entered when auto-negotiation mode is enabled, the cable is disconnected, and by setting
bits [4:3] = 11 in Register 14. When KSZ8895MQX/RQX/FQX/ML is in this mode, all PLL clocks are enabled, MAC is
on, all internal register values will not change, and the host interface is ready for CPU read or write. In this mode, it
mainly controls the PHY transceiver on or off, based on line status to achieve power saving. The PHY continues to
transmit, only turning off the unused receiver block. Once activity resumes, due to plugging a cable or attempting by
the far end to establish link, the KSZ8895MQX/RQX/FQX/ML can automatically enable the PHY to power up to
normal power state from power saving mode.
During power saving mode, the host CPU can set bits [4:3] in Register 14 to change the current power saving mode
to any one of the other three power management operation modes.
Port-based Power Down Mode
In addition, the KSZ8895MQX/RQX/FQX/ML features a per-port power down mode. To save power, a PHY port that
is not in use can be powered down via the Registers Port Control 13 bit 3, or MIIM PHY Registers 0 bit 11.
Functional Overview: Switch Core
Address Look-Up
The internal look-up table stores MAC addresses and their associated information. It contains a 1K unicast address
table plus switching information. The KSZ8895MQX/RQX/FQX/ML is guaranteed to learn 1K addresses and
distinguishes itself from a hash-based look-up table, which, depending on the operating environment and
probabilities, may not guarantee the absolute number of addresses it can learn.
Learning
The internal look-up engine updates its table with a new entry if the following conditions are met:
The received packet’s source address (SA) does not exist in the look-up table.
The received packet is good; the packet has no receiving errors and is of legal length.
The look-up engine inserts the qualified SA into the table, along with the port number and time stamp. If the table is
full, the last entry of the table is deleted first to make room for the new entry.
Migration
The internal look-up engine also monitors whether a station is moved. If this occurs, it updates the table accordingly.
Migration happens when the following conditions are met:
The received packet’s SA is in the table but the associated source port information is different.
The received packet is good; the packet has no receiving errors and is of legal length.
The look-up engine will update the existing record in the table with the new source port information.
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Aging
The look-up engine will update the time stamp information of a record whenever the corresponding SA appears. The
time stamp is used in the aging process. If a record is not updated for a period of time, the look-up engine will
remove the record from the table. The look-up engine constantly performs the aging process and will continuously
remove aging records. The aging period is 300 +/- 75 seconds. This feature can be enabled or disabled through
Register 3 or by external pull-up or pull-down resistors on LED[5][2]. See “Register 3” section.
Forwarding
The KSZ8895MQX/RQX/FQX/ML will forward packets using an algorithm that is depicted in the following flowcharts.
Figure 6 shows stage one of the forwarding algorithm where the search engine looks up the VLAN ID, static table,
and dynamic table for the destination address, and comes up with “port to forward 1” (PTF1). PTF1 is then further
modified by the spanning tree, IGMP snooping, port mirroring, and port VLAN processes to come up with “port to
forward 2” (PTF2), as shown in Figure 7. This is where the packet will be sent.
KSZ8895MQX/RQX/FQX/ML will not forward the following packets:
Error packets. These include framing errors, FCS errors, alignment errors, and illegal size packet errors.
802.3x pause frames. The KSZ8895MQX/RQX/FQX/ML will intercept these packets and perform the appropriate
actions.
“Local” packets. Based on destination address (DA) look-up. If the destination port from the look-up table
matches the port where the packet was from, the packet is defined as “local.”
Switching Engine
The KSZ8895MQX/RQX/FQX/ML features a high-performance switching engine to move data to and from the MAC’s
packet buffers. It operates in store and forward mode, while the efficient switching mechanism reduces overall
latency. The KSZ8895MQX/RQX/FQX/ML has a 64kB internal frame buffer. This resource is shared between all five
ports. There are a total of 512 buffers available. Each buffer is sized at 128B.
Media Access Controller (MAC) Operation
The KSZ8895MQX/RQX/FQX/ML strictly abides by IEEE 802.3 standards to maximize compatibility.
Inter-Packet Gap (IPG)
If a frame is successfully transmitted, the 96-bit time IPG is measured between the two consecutive MTXEN. If the
current packet is experiencing collision, the 96-bit time IPG is measured from MCRS and the next MTXEN.
Backoff Algorithm
The KSZ8895MQX/RQX/FQX/ML implements the IEEE Standard 802.3 binary exponential backoff algorithm, and
optional “aggressive mode” backoff. After 16 collisions, the packet will be optionally dropped, depending on the chip
configuration in Register 3. See “Register 3.”
Late Collision
If a transmit packet experiences collisions after 512-bit times of the transmission, the packet will be dropped.
Illegal Frames
The KSZ8895MQX/RQX/FQX/ML discards frames less than 64 bytes and can be programmed to accept frames up
to 1536 bytes in Register 4. For special applications, the KSZ8895MQX/RQX/FQX/ML can also be programmed to
accept frames up to 1916 bytes in Register 4. Since the KSZ8895MQX/RQX/FQX/ML supports VLAN tags, the
maximum sizing is adjusted when these tags are present.
Flow Control
The KSZ8895MQX/RQX/FQX/ML supports standard 802.3x flow control frames on both transmit and receive sides.
On the receive side, if the KSZ8895MQX/RQX/FQX/ML receives a pause control frame, the
KSZ8895MQX/RQX/FQX/ML will not transmit the next normal frame until the timer, specified in the pause control
frame, expires. If another pause frame is received before the current timer expires, the timer will be updated with the
new value in the second pause frame. During this period (being flow controlled), only flow control packets from the
KSZ8895MQX/RQX/FQX/ML will be transmitted.
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On the transmit side, the KSZ8895MQX/RQX/FQX/ML has intelligent and efficient ways to determine when to invoke
flow control. The flow control is based on availability of the system resources, including available buffers, available
transmit queues and available receive queues.
The KSZ8895MQX/RQX/FQX/ML flow controls a port that has just received a packet if the destination port resource
is busy. The KSZ8895MQX/RQX/FQX/ML issues a flow control frame (XOFF), containing the maximum pause time
defined in IEEE standard 802.3x. Once the resource is freed up, the KSZ8895MQX/RQX/FQX/ML sends out the
other flow control frame (XON) with zero pause time to turn off the flow control (turn on transmission to the port). A
hysteresis feature is also provided to prevent over-activation and deactivation of the flow control mechanism.
The KSZ8895MQX/RQX/FQX/ML flow controls all ports if the receive queue becomes full.
Figure 10. Destination Address Lookup Flow Chart, Stage 1
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Figure 11. Destination Address Resolution Flow Chart, Stage 2
The KSZ8895MQX/RQX/FQX/ML will not forward the following packets:
1. Error packets
These include framing errors, Frame Check Sequence (FCS) errors, alignment errors, and illegal size packet errors.
2. IEEE802.3x PAUSE frames
KSZ8895MQX/RQX/FQX/ML intercepts these packets and performs full duplex flow control accordingly.
3. "Local" packets
Based on destination address (DA) lookup, if the destination port from the lookup table matches the port from which
the packet originated, the packet is defined as "local."
Half-Duplex Back Pressure
The KSZ8895MQX/RQX/FQX/ML also provides a half-duplex back pressure option (note: this is not in IEEE 802.3
standards). The activation and deactivation conditions are the same as the ones given for full-duplex mode. If back
pressure is required, the KSZ8895MQX/RQX/FQX/ML sends preambles to defer the other station's transmission
(carrier sense deference). To avoid jabber and excessive deference as defined in IEEE 802.3 standards, after a
certain period of time, the KSZ8895MQX/RQX/FQX/ML discontinues carrier sense but raises it quickly after it drops
packets to inhibit other transmissions. This short silent time (no carrier sense) is to prevent other stations from
sending out packets and keeps other stations in a carrier sense-deferred state. If the port has packets to send during
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a back pressure situation, the carrier sense-type back pressure is interrupted and those packets are transmitted
instead. If there are no more packets to send, carrier sense-type back pressure becomes active again until switch
resources are free. If a collision occurs, the binary exponential backoff algorithm is skipped and carrier sense is
generated immediately, reducing the chance of further colliding and maintaining carrier sense to prevent reception of
packets. To ensure no packet loss in 10BASE-T or 100BASE-TX half-duplex modes, the user must enable the
following:
Aggressive backoff (Register 3, bit 0)
No excessive collision drop (Register 4, bit 3)
Back pressure (Register 4, bit 5)
These bits are not set as the default because this is not the IEEE standard.
Broadcast Storm Protection
The KSZ8895MQX/RQX/FQX/ML has an intelligent option to protect the switch system from receiving too many
broadcast packets. Broadcast packets are normally forwarded to all ports except the source port and thus use too
many switch resources (bandwidth and available space in transmit queues). The KSZ8895MQX/RQX/FQX/ML has
the option to include “multicast packets” for storm control. The broadcast storm rate parameters are programmed
globally and can be enabled or disabled on a per port basis. The rate is based on a 50ms (0.05s) interval for 100BT
and a 500ms (0.5s) interval for 10BT. At the beginning of each interval, the counter is cleared to zero and the rate
limit mechanism starts to count the number of bytes during the interval. The rate definition is described in Registers 6
and 7. The default setting for Registers 6 and 7 is 0x4A (74 decimal). This is equal to a rate of 1%, calculated as
follows:
148,80 frames/sec X 50ms (0.05s)/interval X 1% = 74 frames/interval (approx.) = 0x4A
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MII Interface Operation
The media-independent interface (MII) is specified by the IEEE 802.3 committee and provides a common interface
between physical layer and MAC layer devices. The KSZ8895MQX/RQX/FQX/ML provides two such interfaces. The
P5-MII interface is used to connect to the fifth PHY, where as the SW-MII interface is used to connect to the fifth
MAC. Each of these MII interfaces contains two distinct groups of signals, one for transmission and the other for
receiving.
Port 5 PHY 5 P5-MII/RMII Interface
The media independent interface (MII) is specified by the IEEE 802.3 committee and provides a common interface
between the physical layer and MAC layer devices. The Reduced Media Independent Interface (RMII) specifies a low
pin count MII. The KSZ8895MQX/RQX/FQX/ML provides two such interfaces for MAC5 and PHY5. The Port 5 PHY5
P5-MII/RMII interface is used to connect to the fifth PHY, where as the SW-MII/RMII interface is used to connect to
the fifth MAC. The KSZ8895MQX/FQX/ML support P5-MII, the KSZ8895RQX supports P5-RMII. Each of these
MII/RMII interfaces contains two distinct groups of signals, one for transmission and the other for receiving. Table 3
describes the signals used in the PHY [5] P5-MII/RMII interface. The P5-MII interface operates in PHY mode only.
Table 4. Port 5 PHY P5-MII/RMII Signals
MII
Signal
Description
KSZ8895MQX/FQX/ML
P5-MII
KSZ8895MQX/FQX/ML
MII Signal Type
KSZ8895RQX
P5-RMII
KSZ8895RQX
RMII Signal
Type
MTXEN
Transmit enable
PMTXEN
I
PMTXEN
I
MTXER
Transmit error
PMTXER
I
MTXD3
Transmit data bit 3
PMTXD[3]
I
MTXD2
Transmit data bit 2
PMTXD[2]
I
MTXD1
Transmit data bit 1
PMTXD[1]
I
PMTXD[1]
I
MTXD0
Transmit data bit 0
PMTXD[0]
I
PMTXD[0]
I
MTXC
Transmit clock
PMTXC
O
PMREFCLK/PMTXC
I
MCOL
Collision detection
PCOL
O
MCRS
Carrier sense
PCRS
O
MRXDV
Receive data valid
PMRXDV
O
PMRXDV
O
MRXER
Receive error
PMRXER
O
PMRXER
O
MRXD3
Receive data bit 3
PMRXD[3]
O
MRXD2
Receive data bit 2
PMRXD[2]
O
MRXD1
Receive data bit 1
PMRXD[1]
O
PMRXD[1]
O
MRXD0
Receive data bit 0
PMRXD[0]
O
PMRXD[0]
O
MRXC
Receive clock
PMRXC
O
PMRXC
O
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Port 5 MAC 5 SW5-MII Interface for the KSZ8895MQX/FQX/ML
Table 4 shows two connection manners:
The first is an external MAC connects to SW5-MII PHY mode.
The second is an external PHY connects to SW5-MII MAC mode.
Please see the pin [91, 86, 87] descriptions for configuration details for the MAC mode and PHY mode. SW5-MII
works with 25MHz clock for 100Base-TX, SW5-MII works with 2.5MHz clock for 10Base-T.
Table 5. Switch MAC5 MII Signals
KSZ8895MQX/FQX/ML PHY Mode Connection
KSZ8895MQX/FQX/ML MAC Mode Connection
External MAC
KSZ8895MQX/FQX/ML
SW5-MII Signals
Type
Description
External
PHY
KSZ8895MQX/FQX/ML
SW5-MII Signals
Type
MTXEN
SMTXEN
Input
Transmit enable
MTXEN
SMRXDV
Output
MTXER
SMTXER
Input
Transmit error
MTXER
Not used
Not used
MTXD3
SMTXD[3]
Input
Transmit data bit 3
MTXD3
SMRXD[3]
Output
MTXD2
SMTXD[2]
Input
Transmit data bit 2
MTXD2
SMRXD[2]
Output
MTXD1
SMTXD[1]
Input
Transmit data bit 1
MTXD1
SMRXD[1]
Output
MTXD0
SMTXD[0]
Input
Transmit data bit 0
MTXD0
SMRXD[0]
Output
MTXC
SMTXC
Output
Transmit clock
MTXC
SMRXC
Input
MCOL
SCOL
Output
Collision detection
MCOL
SCOL
Input
MCRS
SCRS
Output
Carrier sense
MCRS
SCRS
Input
MRXDV
SMRXDV
Output
Receive data valid
MRXDV
SMTXEN
Input
MRXER
Not used
Output
Receive error
MRXER
SMTXER
Input
MRXD3
SMRXD[3]
Output
Receive data bit 3
MRXD3
SMTXD[3]
Input
MRXD2
SMRXD[2]
Output
Receive data bit 2
MRXD2
SMTXD[2]
Input
MRXD1
SMRXD[1]
Output
Receive data bit 1
MRXD1
SMTXD[1]
Input
MRXD0
SMRXD[0]
Output
Receive data bit 0
MRXD0
SMTXD[0]
Input
MRXC
SMRXC
Output
Receive clock
MRXC
SMTXC
Input
The switch MII interface operates in either MAC mode or PHY mode for KSZ8895MQX/FQX/ML. These interfaces
are nibble-wide data interfaces, so they run at one-quarter the network bit rate (not encoded). Additional signals on
the transmit side indicate when data is valid or when an error occurs during transmission. Likewise, the receive side
has indicators that convey when the data is valid and without physical layer errors. For half-duplex operation, there is
a signal that indicates a collision has occurred during transmission.
Note that the signal MRXER is not provided on the MII-SW interface for PHY mode operation and the signal MTXER
is not provided on the SW-MII interface for MAC mode operation. Normally MRXER would indicate a receive error
coming from the physical layer device. MTXER would indicate a transmit error from the MAC device. These signals
are not appropriate for this configuration. For PHY mode operation with an external MAC, if the device interfacing
with the KSZ8895MQX/FQX/ML has an MRXER pin, it should be tied low. For MAC mode operation with an external
PHY, if the device interfacing with the KSZ8895MQX/FQX/ML has an MTXER pin, it should be tied low.
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Port 5 MAC 5 Switch SW5-RMII Interface for the KSZ8895RQX
The Reduced Media Independent Interface (RMII) specifies a low pin count Media Independent Interface (MII). The
KSZ8895RQX supports RMII interface at Port 5 switch side and provides a common interface at MAC5 layer in the
device, and has the following key characteristics:
Supports 10Mbps and 100Mbps data rates.
Uses a single 50MHz clock reference (provided internally or externally): in internal mode, the chip provides a
reference clock from the SMRXC pin to the SMTXC pin and provides the clock to the opposite clock input pin for
RMII interface. In external mode, the chip receives 50MHz reference clock from an external oscillator or opposite
RMII interface.
Provides independent 2-bit wide (bi-bit) transmit and receive data paths.
KSZ8895RQX supports MAC5 RMII interfaces at the switch side:
For the detail of SW5-RMII (Port 5 MAC5 RMII) signals connection see the table below:
The KSZ8895RQX can provide a 50MHz reference clock for both MAC to MAC and MAC to PHY RMII interfaces
when SW5-RMII is used in the clock mode of the device (default with strap pin LED2_2 internal pull-up for the
clock mode).
The KSZ8895RQX can also receive a 50MHz reference clock from an external 50MHz clock source or opposite
RMII to SW5-RMII SMTXC pin when the device is set to normal mode (the strap pin LED2_2 is pulled down).
When the device is strapped to normal mode by pin LED2_2 pull-down, the reference clock comes from SMTXC
which will be used as the device’s clock source. The external 25MHz crystal clock from pins X1/X2 will be ignored.
Note: In normal mode, the 50MHz clock from SMTXC will be used as the clock source for whole device. The PHY5
PMTXC/PMREFCLK pin can’t be used as the clock source for whole device. The pin of PMTXC/PMREFCLK can
receive the 50MHz clock from PMRXC when the device is strapped to normal mode and an external 50MHz
reference clock comes in from pin SMTXC. In normal mode, the 50MHz clock on pin SMRXC can be disabled by
register, and the PMRXC 50MHz clock can be used when P5-RMII interface is used.
There is a Register 12 bit 6 to monitor the status of the device for the clock mode or normal mode.
When using an external 50MHz clock source as RMII reference clock, the KSZ8895RQX should be set to normal
mode by pulling down its LED2_2 strap-in pin first before power up reset or warm reset. The normal mode of the
KSZ8895RQX device will start to work when it gets the 50MHz reference clock from pin SMTXC/SMREFCLK from an
external 50MHz clock source. For the RMII connection examples, please refer to app note in the design kit.
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Table 6. Port 5 MAC5 SW5-RMII Connection
SW5-RMII MAC to MAC Connection
(‘PHY mode’)
SW5-RMII MAC to PHY Connection
(‘MAC mode’)
External
MAC
KSZ8895RQX
SW5-RMII
KSZ8895RQX
SW Signal Type
Description
External
PHY
KSZ8895RQX
SW5-RMII
KSZ8895RQX SW
Signal Type
REF_CLK
xSMRXC
Output (clock
mode with
50MHz)
(Normal mode
without
connection)
Reference Clock
--------
SMTXC/SM
REFCLK
Input (clock comes
from SMRXC in
clock mode or
external clock in
normal mode)
CRS_DV
SMRXDV
/SMCRSDV
Output
Carier sense/Receive
data valid
CRS_DV
SMTXEN
Input
RXD1
SMRXD[1]
Output
Receive data bit 1
RXD1
SMTXD[1]
Input
RXD0
SMRXD[0]
Output
Receive data bit 0
RXD0
SMTXD[0]
Input
TX_EN
SMTXEN
Input
Transmit data enable
TX_EN
SMRXDV
/SMCRSDV
Output
TXD1
SMTXD[1]
Input
Transmit data bit 1
TXD1
SMRXD[1]
Output
TXD0
SMTXD[0]
Input
Transmit data bit 0
TXD0
SMRXD[0]
Output
(not used)
(not used)
Receive error
(not used)
(not used)
---
SMTXC/SM
REFCLK
Input (clock
comes from
SMRXC in clock
mode or external
clock in normal
mode)
Reference Clock
REF_CLK
SMRXC
Output (clock mode
with 50MHz)
(Normal mode
without connection)
Note:
6. MAC/PHY mode in RMII is difference with MAC/PHY mode in MII, there is no strap pin and register configuration request in RMII, just follow
the signals connection in the table.
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SNI Interface Operation
The serial network interface (SNI) is compatible with some controllers used for network layer protocol processing.
This interface can be directly connected to these types of devices. The signals are divided into two groups, one for
transmission and the other for reception. The signals involved are described in Table 7.
Table 7. SNI Signals
SNI Signal
Description
KSZ8895MQX/RQX/FQX/ML
Signal
TXEN
Transmit Enable
SMTXEN
TXD
Serial Transmit Data
SMTXD[0]
TXC
Transmit Clock
SMTXC
COL
Collision Detection
SCOL
CRS
Carrier Sense
SMRXDV
RXD
Serial Receive Data
SMRXD[0]
RXC
Receive Clock
SMRXC
This interface is a bit-wide data interface, so it runs at the network bit rate (not encoded). An additional signal on the
transmit side indicates when data is valid. Likewise, the receive side has an indicator that shows when the data is
valid.
For half-duplex operation there is a signal that indicates a collision has occurred during transmission.
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Advanced Functionality
QoS Priority Support
The KSZ8895MQX/RQX/FQX/ML provides Quality of Service (QoS) for applications such as VoIP and video
conferencing. The KSZ8895MQX/RQX/FQX/ML offers one, two, or four priority queues per port by setting the
Registers port control 9 bit 1 and the Registers port control 0 bit 0, the 1/2/4 queues split as follows,
[Registers port control 9 bit 1, control 0 bit 0] = 00 single output queue as default.
[Registers port control 9 bit 1, control 0 bit 0] = 01 egress port can be split into two priority transmit queues.
[Registers port control 9 bit 1, control 0 bit 0] = 10 egress port can be split into four priority transmit queues.
The four priority transmit queue is a new feature in the KSZ8895MQX/RQX/FQX/ML. The queue 3 is the highest
priority queue and queue 0 is the lowest priority queue. The port Registers xxx control 9 bit 1 and the Registers port
control 0 bit 0 are used to enable split transmit queues for ports 1, 2, 3, 4 and 5, respectively. If a port's transmit
queue is not split, high priority and low priority packets have equal priority in the transmit queue.
There is an additional option to either always deliver high priority packets first or to use programmable weighted fair
queuing for the four priority queue scale by the Registers Port Control 10, 11, 12 and 13 (default value are 8, 4, 2, 1
by their bit [6:0].
Register 130 bit [7:6] Prio_2Q[1:0] is used when the 2 Queue configuration is selected, these bits are used to map
the 2-bit result of IEEE 802.1p from the Registers 128, 129 or TOS/DiffServ mapping from Registers 144-159 (for 4
Queues) into two-queue mode with priority high or low.
Please see the descriptions of the Register 130 bits [7:6] for detail.
Port-Based Priority
With port-based priority, each ingress port is individually classified as a priority 0-3 receiving port. All packets
received at the priority 3 receiving port are marked as high priority and are sent to the high-priority transmit queue if
the corresponding transmit queue is split. The Port Registers Control 0 bits [4:3] is used to enable port-based priority
for ports 1, 2, 3, 4 and 5, respectively.
802.1p-Based Priority
For 802.1p-based priority, the KSZ8895MQX/RQX/FQX/ML examines the ingress (incoming) packets to determine
whether they are tagged. If tagged, the 3-bit priority field in the VLAN tag is retrieved and compared against the
“priority mapping” value, as specified by the Registers 128 and 129, both Register 128/129 can map 3-bit priority field
of 0-7 value to 2-bit result of 0-3 priority levels. The “priority mapping” value is programmable.
The following figure illustrates how the 802.1p priority field is embedded in the 802.1Q VLAN tag.
Figure 12. 802.1p Priority Field Format
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802.1p-based priority is enabled by bit [5] of the Registers Port Control 0 for ports 1, 2, 3, 4 and 5, respectively.
The KSZ8895MQX/RQX/FQX/ML provides the option to insert or remove the priority tagged frame's header at each
individual egress port. This header, consisting of the two-byte VLAN Protocol ID (VPID) and the two-byte Tag Control
Information field (TCI), is also referred to as the IEEE 802.1Q VLAN tag.
Tag Insertion is enabled by bit [2] of the Registers Port Control 0 and the Register Port Control 8 to select which
source port (ingress port) PVID can be inserted on the egress port for ports 1, 2, 3, 4 and 5, respectively. At the
egress port, untagged packets are tagged with the ingress port’s default tag. The default tags are programmed in the
Registers Port Control 3 and control 4 for ports 1, 2, 3, 4 and 5, respectively. The KSZ8895MQX/RQX/FQX/ML will
not add tags to already tagged packets.
Tag Removal is enabled by bit [1] of the Registers Port Control 0 for ports 1, 2, 3, 4 and 5, respectively. At the
egress port, tagged packets will have their 802.1Q VLAN tags removed. The KSZ8895MQX/RQX/FQX/ML will not
modify untagged packets.
The CRC is recalculated for both tag insertion and tag removal.
802.1p Priority Field Re-mapping is a QoS feature that allows the KSZ8895MQX/RQX/FQX/ML to set the “User
Priority Ceiling” at any ingress port by the Register Port Control 2 bit 7. If the ingress packet’s priority field has a
higher priority value than the default tag’s priority field of the ingress port, the packet’s priority field is replaced with
the default tag’s priority field.
DiffServ-Based Priority
DiffServ-based priority uses the ToS Registers (Registers 144 to 159) in the Advanced Control Registers section.
The ToS priority control registers implement a fully decoded, 128-bit Differentiated Services Code Point (DSCP)
register to determine packet priority from the 6-bit ToS field in the IP header. When the most significant six bits of the
ToS field are fully decoded, 64 code points for DSCP result. These are compared with the corresponding bits in the
DSCP register to determine priority.
Spanning Tree Support
Port 5 is the designated port for spanning tree support.
The other ports (Port 1 - Port 4) can be configured in one of the five spanning tree states via “transmit enable,”
“receive enable,” and “learning disable” register settings in Registers 18, 34, 50, and 66 for Ports 1, 2, 3, and 4,
respectively. The following description shows the port setting and software actions taken for each of the five
spanning tree states.
Disable state: the port should not forward or receive any packets. Learning is disabled.
Port setting: "transmit enable = 0, receive enable = 0, learning disable = 1."
Software action: the processor should not send any packets to the port. The switch may still send specific packets to
the processor (packets that match some entries in the static table with “overriding bit” set) and the processor should
discard those packets. Note: the processor is connected to Port 5 via MII interface. Address learning is disabled on
the port in this state.
Blocking state: only packets to the processor are forwarded. Learning is disabled.
Port setting: "transmit enable = 0, receive enable = 0, learning disable = 1"
Software action: the processor should not send any packets to the port(s) in this state. The processor should
program the “Static MAC table” with the entries that it needs to receive (e.g., BPDU packets). The “overriding” bit
should also be set so that the switch will forward those specific packets to the processor. Address learning is
disabled on the port in this state.
Listening state: only packets to and from the processor are forwarded. Learning is disabled.
Port setting: "transmit enable = 0, receive enable = 0, learning disable = 1.
"Software action: The processor should program the static MAC table with the entries that it needs to receive (e.g.
BPDU packets). The “overriding” bit should be set so that the switch will forward those specific packets to the
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processor. The processor may send packets to the port(s) in this state, see “Tail Tagging Mode” section for details.
Address learning is disabled on the port in this state.
Learning state: only packets to and from the processor are forwarded. Learning is enabled.
Port setting: “transmit enable = 0, receive enable = 0, learning disable = 0.”
Software action: The processor should program the static MAC table with the entries that it needs to receive (e.g.,
BPDU packets). The “overriding” bit should be set so that the switch will forward those specific packets to the
processor. The processor may send packets to the port(s) in this state, see “Tail Tagging Mode” section for details.
Address learning is enabled on the port in this state.
Forwarding state: packets are forwarded and received normally. Learning is enabled.
Port setting: “transmit enable = 1, receive enable = 1, learning disable = 0.”
Software action: The processor should program the static MAC table with the entries that it needs to receive (e.g.,
BPDU packets). The “overriding” bit should be set so that the switch will forward those specific packets to the
processor. The processor may send packets to the port(s) in this state, see “Tail Tagging Mode” section for details.
Address learning is enabled on the port in this state.
Rapid Spanning Tree Support
There are three operational states of Discarding, Learning, and Forwarding assigned to each port for RSTP:
Discarding ports do not participate in the active topology and do not learn MAC addresses.
Discarding state: the state includes three states of the disable, blocking and listening of STP.
Port setting: "transmit enable = 0, receive enable = 0, learning disable = 1."
Software action: the processor should not send any packets to the port. The switch may still send specific packets to
the processor (packets that match some entries in the static table with “overriding bit” set) and the processor should
discard those packets. When disabling the port’s learning capability (learning disable = ’1’), set the Register 1 bit 5
and bit 4 will flush rapidly with the port related entries in the dynamic MAC table and static MAC table.
Note: the processor is connected to Port 5 via MII interface. Address learning is disabled on the port in this state.
Ports in Learning states learn MAC addresses, but do not forward user traffic.
Learning state: only packets to and from the processor are forwarded. Learning is enabled.
Port setting: “transmit enable = 0, receive enable = 0, learning disable = 0.”
Software action: The processor should program the static MAC table with the entries that it needs to receive (e.g.,
BPDU packets). The “overriding” bit should be set so that the switch will forward those specific packets to the
processor. The processor may send packets to the port(s) in this state, see “Tail Tagging Mode” section for details.
Address learning is enabled on the port in this state.
Ports in Forwarding states fully participate in both data forwarding and MAC learning.
Forwarding state: packets are forwarded and received normally. Learning is enabled.
Port setting: “transmit enable = 1, receive enable = 1, learning disable = 0.”
Software action: The processor should program the static MAC table with the entries that it needs to receive (e.g.,
BPDU packets). The “overriding” bit should be set so that the switch will forward those specific packets to the
processor. The processor may send packets to the port(s) in this state, see “Tail Tagging Mode” section for details.
Address learning is enabled on the port in this state.
RSTP uses only one type of BPDU called RSTP BPDUs. They are similar to STP Configuration BPDUs with the
exception of a type field set to “version 2” for RSTP and “version 0” for STP, and a flag field carrying additional
information.
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Tail Tagging Mode
The Tail Tag is only seen and used by the Port 5 interface, which should be connected to a processor by SW5-
MII/RMII interface. The one byte tail tagging is used to indicate the source/destination port in Port 5. Only bit [3-0] are
used for the destination in the tail tagging byte. Other bits are not used. The Tail Tag feature is enabled by setting
Register 12 bit 1.
Figure 13. Tail Tag Frame Format
Table 8. Tail Tag Rules
Ingress to Port 5 (Host --> KSZ8895MQX/RQX/FQX/ML)
Bit [3:0]
Destination
0,0,0,0
Reserved
0,0,0,1
Port 1 (direct forward to Port1)
0,0,1,0
Port 2 (direct forward to Port2)
0,1,0,0
Port 3 (direct forward to Port3)
1,0,0,0
Port 4 (direct forward to Port4)
1,1,1,1
Port 1, 2,3 and 4 (direct forward to Port 1,2,3,4,)
Bit[7:4]
0,0,0,0
Queue 0 is used at destination port
0,0,0,1
Queue 1 is used at destination port
0,0,1,0
Queue 2 is used at destination port
0,0,1,1
Queue 3 is used at destination port
x, 1,x,x
Anyhow send packets to specified port in bit [3:0]
1, x,x,x
Bit[6:0] will be ignored as normal (Address look-up)
Egress from Port 5 (KSZ8895MQX/RQX/FQX/ML --> Host)
Bit [1:0]
Source
0,0
Port 1 (packets from Port 1)
0,1
Port 2 (packets from Port 2)
1,0
Port 3 (packets from Port 3)
1,1
Port 4 (packets from Port 4)
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IGMP Support
There are two parts involved to support the Internet Group Management Protocol (IGMP) in Layer 2. The first part is
IGMP snooping, the second part is this IGMP packet to be sent back to the subscribed port. Describe them as
follows.
IGMP Snooping
The KSZ8895MQX/RQX/FQX/ML traps IGMP packets and forwards them only to the processor (Port 5 SW5-
MII/RMII). The IGMP packets are identified as IP packets (either Ethernet IP packets, or IEEE 802.3 SNAP IP
packets) with IP version = 0x4 and protocol version number = 0x2. Set Register 5 bit [6] to ‘1’ to enable IGMP
snooping.
IGMP Send Back to the Subscribed Port
Once the host responds the received IGMP packet, the host should know the original IGMP ingress port and send
back the IGMP packet to this port only, otherwise this IGMP packet will be broadcasted to all port to downgrade the
performance.
Enable the tail tag mode, the host will know the IGMP packet received port from tail tag bits [1:0] and can send back
the response IGMP packet to this subscribed port by setting the bits [3:0] in the tail tag. Enable “Tail tag mode” by
setting Register 12 bit 1.
Port Mirroring Support
The KSZ8895MQX/RQX/FQX/ML supports “port mirror” comprehensively as:
“Receive Only” mirror on a port
All the packets received on the port will be mirrored on the sniffer port. For example, Port 1 is programmed to be “rx
sniff,” and Port 5 is programmed to be the “sniffer port.” A packet, received on Port 1, is destined to Port 4 after the
internal look-up. The KSZ8895MQX/RQX/FQX/ML will forward the packet to both Port 4 and Port 5.
KSZ8895MQX/RQX/FQX/ML can optionally forward even “bad” received packets to Port 5.
“Transmit Only” mirror on a port
All the packets transmitted on the port will be mirrored on the sniffer port. For example, Port 1 is programmed to be
“tx sniff,” and Port 5 is programmed to be the “sniffer port.” A packet, received on any of the ports, is destined to Port
1 after the internal look-up. The KSZ8895MQX/RQX/FQX/ML will forward the packet to both Ports 1 and 5.
“Receive and Transmit” mirror on two ports
All the packets received on port A AND transmitted on port B will be mirrored on the sniffer port. To turn on the “AND”
feature, set Register 5 bit 0 to 1. For example, Port 1 is programmed to be “rx sniff,” Port 2 is programmed to be
“transmit sniff,” and Port 5 is programmed to be the “sniffer port.” A packet, received on Port 1, is destined to Port 4
after the internal look-up. The KSZ8895MQX/RQX/FQX/ML will forward the packet to Port 4 only, since it does not
meet the “AND” condition. A packet, received on Port 1, is destined to Port 2 after the internal look-up. The
KSZ8895MQX/RQX/FQX/ML will forward the packet to both Port 2 and Port 5.
Multiple ports can be selected to be “rx sniffed” or “tx sniffed.” And any port can be selected to be the “sniffer port.”
All these per port features can be selected through Register 17.
VLAN Support
The KSZ8895MQX/RQX/FQX/ML supports 128 active VLANs and 4096 possible VIDs specified in IEEE 802.1q.
KSZ8895MQX/RQX/FQX/ML provides a 128-entry VLAN table, which correspond to 4096 possible VIDs and
converts to FID (7 bits) for address look-up max 128 active VLANs. If a non-tagged or null-VID-tagged packet is
received, then the ingress port VID is used for look-up when 802.1q is enabled by the global Register 5 control 3 bit
7. In the VLAN mode, the look-up process starts from VLAN table look-up to determine whether the VID is valid. If
the VID is not valid, the packet will then be dropped and its address will not be learned. If the VID is valid, FID is
retrieved for further look-up by the static MAC table or dynamic MAC table. FID+DA is used to determine the
destination port. The following table describes the different actions in different situations of DA and FID+DA in the
static MAC table and dynamic MAC table after the VLAN table finish a look-up action. FID+SA is used for learning
purposes. The following table also describes learning in the dynamic MAC table when the VLAN table has done a
look-up in the static MAC table without a valid entry.
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Table 9. FID+DA Look-Up in the VLAN Mode
DA found in
Static MAC table
USE FID
Flag?
FID Match?
DA+FID found in
Dynamic MAC table
Action
No
Do Not care
Do Not care
No
Broadcast to the membership ports defined in
the VLAN table bit [11:7].
No
Do Not care
Do Not care
Yes
Send to the destination port defined in the
dynamic MAC table bit [58:56].
Yes
0
Do Not care
Do Not care
Send to the destination port(s) defined in the
static MAC table bit [52:48].
Yes
1
No
No
Broadcast to the membership ports defined in
the VLAN table bit [11:7].
Yes
1
No
Yes
Send to the destination port defined in the
dynamic MAC table bit [58:56].
Yes
1
Yes
Do Not care
Send to the destination port(s) defined in the
static MAC table bit [52:48].
Table 10. FID+SA Look-Up in the VLAN Mode
SA+FID found in
Dynamic MAC table
Action
No
The SA+FID will be learned into the dynamic table.
Yes
Time stamp will be updated.
Advanced VLAN features are also supported in KSZ8895MQX/RQX/FQX/ML, such as “VLAN ingress filtering” and
“discard non PVID” defined in bits [6:5] of the port Register Control 2. These features can be controlled on a port
basis.
Rate Limiting Support
The KSZ8895MQX/RQX/FQX/ML provides a fine resolution hardware rate limiting. The rate step is 64Kbps when the
rate limit is less than 1Mbps rate for 100BT or 10BT. The rate step is 1Mbps when the rate limit is more than 1Mbps
rate for 100BT or 10BT (refer to Data Rate Selection Table which follow the end of the Port Register Queue 0-3
Ingress/Egress Limit Control section). The rate limit is independently on the “receive side” and on the “transmit side”
on a per port basis. For 10BASE-T, a rate setting above 10 Mbps means the rate is not limited. On the receive side,
the data receive rate for each priority at each port can be limited by setting up Ingress Rate Control Registers. On the
transmit side, the data transmit rate for each priority queue at each port can be limited by setting up Egress Rate
Control Registers. The size of each frame has options to include minimum IFG (Inter Frame Gap) or Preamble byte,
in addition to the data field (from packet DA to FCS).
Ingress Rate Limit
For ingress rate limiting, KSZ8895MQX/RQX/FQX/ML provides options to selectively choose frames from all types,
multicast, broadcast, and flooded unicast frames by bits [3-2] of the port rate limit control register. The
KSZ8895MQX/RQX/FQX/ML counts the data rate from those selected type of frames. Packets are dropped at the
ingress port when the data rate exceeds the specified rate limit or the flow control takes effect without packet
dropped when the ingress rate limit flow control is enabled by the port rate limit control register bit 4. The ingress rate
limiting supports the port-based, 802.1p and DiffServ-based priorities, the port-based priority is fixed priority 0-3
selection by bits [4-3] of the Register Port Control 0. The 802.1p and DiffServ-based priority can be mapped to
priority 0-3 by default of the Register 128 and 129. In the ingress rate limit, set Register 135 global control 19 bit 3 to
enable queue-based rate limit if using two-queue or four-queue mode. All related ingress ports and egress port
should be split to two-queue or four-queue mode by the Registers Port Control 9 and control 0. The four-queue mode
will use Q0-Q3 for priority 0-3 by bit [6-0] of the port Register ingress limit control 1-4. The two-queue mode will use
Q0-Q1 for priority 0-1by bit [6-0] of the port Register ingress limit control 1-2. The priority levels in the packets of the
802.1p and DiffServ can be programmed to priority 0-3 by the Register 128 and 129 for a re-mapping.
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Egress Rate Limit
For egress rate limiting, the Leaky Bucket algorithm is applied to each output priority queue for shaping output traffic.
Interframe gap is stretched on a per frame base to generate smooth, non-burst egress traffic. The throughput of each
output priority queue is limited by the egress rate specified by the data rate selection table followed the egress rate
limit control registers.
If any egress queue receives more traffic than the specified egress rate throughput, packets may be accumulated in
the output queue and packet memory. After the memory of the queue or the port is used up, packet dropping or flow
control will be triggered. As a result of congestion, the actual egress rate may be dominated by flow control/dropping
at the ingress end, and may be therefore slightly less than the specified egress rate. The egress rate limiting
supports the port-based, 802.1p and DiffServ-based priorities, the port-based priority is fixed priority 0-3 selection by
bits [4-3] of the Register Port Control 0. The 802.1p and DiffServ-based priority can be mapped to priority 0-3 by
default of the Register 128 and 129. In the egress rate limit, set Register 135 global control 19 bit 3 for queue-based
rate limit to be enabled if using two-queue or four-queue mode. All related ingress ports and egress port should be
split to two-queue or four-queue mode by the Registers Port Control 9 and control 0. The four-queue mode will use
Q0-Q3 for priority 0-3 by bit [6-0] of the port Register egress limit control 1-4. The two-queue mode will use Q0-Q1 for
priority 0-1by bit [6-0] of the port Register egress limit control 1-2. The priority levels in the packets of the 802.1p and
DiffServ can be programmed to priority 0-3 by the Register 128 and 129 for a re-mapping.
When the egress rate is limited, just use one queue per port for the egress port rate limit. The priority packets will be
based upon the data rate selection table (see Tables 13 and 14). If the egress rate limit uses more than one queue
per port for the egress port rate limit, then the highest priority packets will be based upon the data rate selection table
for the rate limit exact number. Other lower priority packet rates will be limited based upon 8:4:2:1 (default) priority
ratio, which is based on the highest priority rate. The transmit queue priority ratio is programmable.
To reduce congestion, it is good practice to make sure the egress bandwidth exceeds the ingress bandwidth.
Transmit Queue Ratio Programming
In transmit queues 0-3 of the egress port, the default priority ratio is 8:4:2:1. The priority ratio can be programmed by
the Registers Port Control 10, 11, 12 and 13. When the transmit rate exceeds the ratio limit in the transmit queue, the
transmit rate will be limited by the transmit queue 0-3 ratio of the Register Port Control 10, 11, 12 and 13. The
highest priority queue will not be limited. Other lower priority queues will be limited based on the transmit queue ratio.
Filtering for Self-Address, Unknown Unicast/Multicast Address and Unknown VID Packet/IP Multicast
Enable Self-address filtering, the unknown unicast packet filtering and forwarding by the Register 131 Global Control
15. Enable Unknown multicast packet filtering and forwarding by the Register 132 Global Control 16.
Enable Unknown VID packet filtering and forwarding by the Register 133 Global Control 17.
Enable Unknown IP multicast packet filtering and forwarding by the Register 134 Global Control 18.
This function is very useful in preventing packets that could degrade the quality of the port in applications such as
voice over Internet Protocol (VoIP) and the daisy chain connection.
Configuration Interface
I2C Master Serial Bus Configuration
If a 2-wire EEPROM exists, then the KSZ8895MQX/RQX/FQX/ML can perform more advanced features like
broadcast storm protection and rate control. The EEPROM should have the entire valid configuration data from
Register 0 to Register 255 defined in the “Memory Map,” except the chipID = 0 in the Register1 and the status
registers. After reset, the KSZ8895MQX/RQX/FQX/ML will start to read all 255 registers sequentially from the
EEPROM. The configuration access time (tprgm) is less than 30ms, as shown in Figure 6.
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Figure 14. KSZ8895MQX/RQX/FQX/ML EEPROM Configuration Timing Diagram
To configure the KSZ8895MQX/RQX/FQX/ML with a pre-configured EEPROM use the following steps:
1. At the board level, connect pin 110 on the KSZ8895MQX/RQX/FQX/ML to the SCL pin on the EEPROM.
Connect pin 111 on the KSZ8895MQX/RQX/FQX/ML to the SDA pin on the EEPROM.
2. A[2-0] address pins of EEPROM should be tied to ground for address A[2-0] = ‘000’ to be identified by the
KSZ8895MQX/RQX/FQX/ML.
3. Set the input signals PS[1:0] (pins 113 and 114, respectively) to “00.” This puts the KSZ8895MQX/RQX/FQX/ML
serial bus configuration into I2C master mode.
4. Be sure the board-level reset signal is connected to the KSZ8895MQX/RQX/FQX/ML reset signal on pin 115
(RST_N).
5. Program the contents of the EEPROM before placing it on the board with the desired configuration data. Note
that the first byte in the EEPROM must be “95” for the loading to occur properly. If this value is not correct, all
other data will be ignored.
6. Place EEPROM on the board and power up the board. Assert the active-low board level reset to RST_N on the
KSZ8895MQX/RQX/FQX/ML. After the reset is de-asserted, the KSZ8895MQX/RQX/FQX/ML will begin reading
configuration data from the EEPROM. The configuration access time (tprgm) is less than 30ms.
Note: For proper operation, make sure that pin 47 (PWRDN_N) is not asserted during the reset operation.
SPI Slave Serial Bus Configuration
The KSZ8895MQX/RQX/FQX/ML can also act as a SPI slave device. Through the SPI, the entire feature set can be
enabled, including “VLAN,” “IGMP snooping,” “MIB counters,” etc. The external master device can access any
register from Register 0 to Register 255 randomly. The system should configure all the desired settings before
enabling the switch in the KSZ8895MQX/RQX/FQX/ML. To enable the switch, write a "1" to Register 1 bit 0.
Two standard SPI commands are supported (00000011 for “READ DATA,” and 00000010 for “WRITE DATA”). To
speed configuration time, the KSZ8895MQX/RQX/FQX/ML also supports multiple reads or writes. After a byte is
written to or read from the KSZ8895MQX/RQX/FQX/ML, the internal address counter automatically increments if the
SPI Slave Select Signal (SPIS_N) continues to be driven low. If SPIS_N is kept low after the first byte is read, the
next byte at the next address will be shifted out on SPIQ. If SPIS_N is kept low after the first byte is written, bits on
the Master Out Slave Input (SPID) line will be written to the next address. Asserting SPIS_N high terminates a read
or write operation. This means that the SPIS_N signal must be asserted high and then low again before issuing
another command and address. The address counter wraps back to zero once it reaches the highest address.
Therefore the entire register set can be written to or read from by issuing a single command and address.
The default SPI clock speed is 12.5MHz. The KSZ8895MQX/RQX/FQX/ML is able to support a SPI bus up to 25MHz
(set Register 12 bit [5:4] = 0x10). A high performance SPI master is recommended to prevent internal counter
overflow.
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To use the KSZ8895MQX/RQX/FQX/ML SPI:
1. At the board level, connect KSZ8895MQX/RQX/FQX/ML pins as follows:
Table 11. SPI Connections
KSZ8895MQX/RQX/FQX/ML
Pin Number
KSZ8895MQX/RQX/FQX/ML
Signal Name
Microprocessor Signal Description
112
SPIS_N
SPI Slave Select
110
SPIC
SPI Clock
111
SPID
Master Out Slave Input
109
SPIQ
Master In Slave Output
2. Set the input signals PS[1:0] (pins 113 and 114, respectively) to “10” to set the serial configuration to SPI slave
mode.
3. Power up the board and assert a reset signal. After reset wait 100µs, the start switch bit in Register 1 will be set
to ‘0’. Configure the desired settings in the KSZ8895MQX/RQX/FQX/ML before setting the start register to ‘1.'
4. Write configuration to registers using a typical SPI write data cycle as shown in Figure 7 or SPI multiple write as
shown in Figure 9. Note that data input on SPID is registered on the rising edge of SPIC.
5. Registers can be read and configuration can be verified with a typical SPI read data cycle as shown in Figure 8
or a multiple read as shown in Figure 10. Note that read data is registered out of SPIQ on the falling edge of
SPIC.
6. After configuration is written and verified, write a ‘1’ to Register 1 bit 0 to begin KSZ8895MQX/RQX/FQX/ML
switch operation.
Figure 15. SPI Write Data Cycle
Figure 16. SPI Read Data Cycle
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Figure 17. SPI Multiple Write
Figure 18. SPI Multiple Read
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MII Management Interface (MIIM)
The KSZ8895MQX/RQX/FQX/ML supports the standard IEEE 802.3 MII Management Interface, also known as the
Management Data Input/Output (MDIO) Interface. This interface allows upper-layer devices to monitor and control
the states of the KSZ8895MQX/RQX/FQX/ML. An external device with MDC/MDIO capability is used to read the
PHY status or configure the PHY settings. Further details on the MIIM interface are found in Clause 22.2.4.5 of the
IEEE 802.3u Specification.
The MIIM interface consists of the following:
A physical connection that incorporates the data line (pin 108 MDIO) and the clock line (pin 107 MDC).
A specific protocol that operates across the aforementioned physical connection that allows an external controller
to communicate with the KSZ8895MQX/RQX/FQX/ML device.
Access to a set of eight 16-bit registers, consisting of 8 standard MIIM Registers [0:5h], 1d and 1f MIIM registers
per port.
The MIIM Interface can operate up to a maximum clock speed of 10MHz MDC clock.
The following table depicts the MII Management Interface frame format.
Table 12. MII Management Interface Frame Format
Preamble
Start of
Frame
Read/Write
OP Code
PHY
Address
Bits[4:0]
REG
Address
Bits[4:0]
TA
Data Bits[15:0]
Idle
Read
32 1’s
01
10
AAAAA
RRRRR
Z0
DDDDDDDD_DDDDDDDD
Z
Write
32 1’s
01
01
AAAAA
RRRRR
10
DDDDDDDD_DDDDDDDD
Z
The MIIM interface does not have access to all the configuration registers in the KSZ8895MQX/RQX/FQX/ML. It can
only access the standard MIIM registers. See “MIIM Registers”. The SPI interface and MDC/MDIO SMI mode, on the
other hand, can be used to access all registers with the entire KSZ8895MQX/RQX/FQX/ML feature set.
Serial Management Interface (SMI)
The SMI is the KSZ8895MQX/RQX/FQX/ML non-standard MIIM interface that provides access to all
KSZ8895MQX/RQX/FQX/ML configuration registers. This interface allows an external device with MDC/MDIO
interface to completely monitor and control the states of the KSZ8895MQX/RQX/FQX/ML.
The SMI interface consists of the following:
A physical connection that incorporates the data line (MDIO) and the clock line (MDC).
A specific protocol that operates across the aforementioned physical connection that allows an external controller
to communicate with the KSZ8895MQX/RQX/FQX/ML device.
Access to all KSZ8895MQX/RQX/FQX/ML configuration registers. Register access includes the Global, Port and
Advanced Control Registers 0-255 (0x00 – 0xFF), and indirect access to the standard MIIM Registers [0:5] and
custom MIIM Registers [29, 31].
The SMI Interface can operate up to a maximum clock speed of 10MHz MDC clock.
The following table depicts the SMI frame format.
Table 13. Serial Management Interface (SMI) Frame Format
Preamble
Start of
Frame
Read/Write
OP Code
PHY
Address
Bits[4:0]
REG
Address
Bits[4:0]
TA
Data
Bits[15:0]
Idle
Read
32 1’s
01
10
RR11R
RRRRR
Z0
0000_0000_DDDD_DDDD
Z
Write
32 1’s
01
01
RR11R
RRRRR
10
xxxx_xxxx_DDDD_DDDD
Z
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SMI register Read access is selected when OP Code is set to “10” and bits [2:1] of the PHY address is set to ‘11’.
The 8-bit register address is the concatenation of {PHY address bits [4:3], PHY address bits [0], REG address bit
[4:0]}. TA is turn-around bits. TA bits [1:0] are ’Z0’ means the processor MDIO pin is changed to input Hi-Z from
output mode and the followed ‘0’ is the read response from device, as the switch configuration registers are 8-bit
wide, only the lower 8 bits of data bits [15:0] are used
SMI register Write access is selected when OP Code is set to “01” and bits [2:1] of the PHY address is set to ‘11’.
The 8-bit register address is the concatenation of {PHY address bits [4:3], PHY address bits [0], REG address bit
[4:0]}. TA bits [1:0] are set to ’10’, as the switch configuration registers are 8-bit wide, only the lower 8 bits of data bits
[15:0] are used.
To access the KSZ8895MQX/RQX/FQX/ML Registers 0-255 (0x00 - 0xFF), the following applies:
PHYAD [4, 3, 0] and REGAD [4:0] are concatenated to form the 8-bit address; that is, {PHYAD [4, 3, 0], REGAD
[4:0]} = bits [7:0] of the 8-bit address.
Registers are 8 data bits wide. For read operation, data bits [15:8] are read back as zeroes. For write operation, data
bits [15:8] are not defined, and hence can be set to either zeroes or ones.
SMI register access is the same as the MIIM register access, except for the register access requirements presented
in this section.
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Register Description
Offset
Decimal
Hex
Description
0-1
0x00-0x01
Chip ID Registers.
2-13
0x02-0x0D
Global Control Registers.
14-15
0x0E-0x0F
Power Down Management Control Registers.
16-20
0x10-0x14
Port 1 Control Registers.
21-23
0x15-0x17
Port 1 Reserved (Factory Test Registers).
24-31
0x18-0x1F
Port 1 Control/Status Registers.
32-36
0x20-0x24
Port 2 Control Registers.
37-39
0x25-0x27
Port 2 Reserved (Factory Test Registers).
40-47
0x28-0x2F
Port 2 Control/Status Registers.
48-52
0x30-0x34
Port 3 Control Registers.
53-55
0x35-0x37
Port 3 Reserved (Factory Test Registers).
56-63
0x38-0x3F
Port 3 Control/Status Registers.
64-68
0x40-0x44
Port 4 Control Registers.
69-71
0x45-0x47
Port 4 Reserved (Factory Test Registers).
72-79
0x48-0x4F
Port 4 Control/Status Registers.
80-84
0x50-0x54
Port 5 Control Registers.
85-87
0x55-0x57
Port 5 Reserved (Factory Test Registers).
88-95
0x58-0x5F
Port 5 Control/Status Registers.
96-103
0x60-0x67
Reserved (Factory Testing Registers).
104-109
0x68-0x6D
MAC Address Registers.
110-111
0x6E-0x6F
Indirect Access Control Registers.
112-120
0x70-0x78
Indirect Data Registers.
121-123
0x79-0x7B
Reserved (Factory Testing Registers).
124-125
0x7C-0x7D
Port Interrupt Registers.
126-127
0x7E-0x7F
Reserved (Factory Testing Registers).
128-135
0x80-0x87
Global Control Registers.
136
0x88
Switch Self Test Control Register.
137-143
0x89-0x8F
QM Global Control Registers.
144-145
0x90-0x91
TOS Priority Control Registers.
146-159
0x92-0x9F
TOS Priority Control Registers.
160-175
0xA0-0xAF
Reserved (Factory Testing Registers).
176-190
0xB0-0xBE
Port 1 Control Registers.
191
0xBF
Reserved (Factory Testing Register): Transmit Queue Remap Base Register.
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Offset
Decimal
Hex
Description
192-206
0xC0-0xCE
Port 2 Control Registers.
207
0xCF
Reserved (Factory Testing Register).
208-222
0xD0-0xDE
Port 3 Control Registers.
223
0xDF
Reserved (Factory Testing Register).
224-238
0xE0-0xEE
Port 4 Control Registers.
239
0xEF
Reserved (Factory Testing Register).
240-254
0xF0-0xFE
Port 5 Control Registers.
255
0xFF
Reserved (Factory Testing Register).
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Global Registers
Address
Name
Description
Mode
Default
Register 0 (0x00): Chip ID0
7-0
Family ID
Chip family.
RO
0x95
Register 1 (0x01): Chip ID1 / Start Switch
7-4
Chip ID
0100 = KSZ8895MQX/FQX/ML
0110 = KSZ8995RQX
RO
0x4 is for MQX,
FQX, and ML
0x6 is for RQX
3-1
Revision ID
Revision ID
RO
0x0
0
Start Switch
1, Start the chip when external pins (PS1, PS0) = (1,0)
Note: in (PS1,PS0) = (0,0) mode, the chip will
start automatically, after trying to read the external
EEPROM. If EEPROM does not exist, the chip will use default
values for all internal registers. If EEPROM is present, the
contents in the EEPROM will be checked.
The switch will check:
(1) Register 0 = 0x95.
(2) Register 1 [7:4] = 0x0.
If this check is OK, the contents in the EEPROM will override
chip register default values =0, chip will not start when
external pins
(PS1, PS0) = (1,0) or (0,1).
Note: (PS1, PS0) = (1,1) for Factory test only.
0, stop the switch function of the chip.
R/W
0
Register 2 (0x02): Global Control 0
7
New Back-off Enable
New Back-off algorithm designed for UNH
1 = Enable
0 = Disable
R/W
0
6
Reserved
Reserved.
RO
0
5
Flush dynamic MAC table
Flush the entire dynamic MAC table for RSTP
1 = Trigger the flush dynamic MAC table operation.
This bit is self clear
0 = normal operation
Note: All the entries associated with a port that has its
learning capability being turned off (Learning Disable) will be
flushed. If you want to flush the entire Table, all ports learning
capability must be turned off.
R/W
(SC)
0
4
Flush static MAC table
Flush the matched entries in static MAC table for RSTP
1 = Trigger the flush static MAC table operation. This
bit is self clear
0 = normal operation
Note: The matched entry is defined as the entry whose
Forwarding Ports field contains a single port and MAC
address with unicast. This port, in turn, has its learning
capability being turned off (Learning Disable). Per port,
multiple entries can be qualified as matched entries.
R/W
(SC)
0
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Global Registers (Continued)
Address
Name
Description
Mode
Default
3
Enable PHY MII/RMII
1, enable PHY P5-MII/RMII interface (default).
Note: if not enabled, the switch will be tri-state all
outputs.
R/W
1
Pin LED[5][1]
strap option.
PD(0): isolate.
PU(1): Enable.
Note: LED[5][1]
has internal
pull-up (PU).
2
Reserved
N/A, do not change
RO
1
1
UNH Mode
1, the switch will drop packets with 0x8808 in T/L filed,
or DA = 01-80-C2-00-00-01.
0, the switch will drop packets qualified as “flow control”
packets.
R/W
0
0
Link Change Age
1, link change from “link” to “no link” will cause fast
aging (<800µs) to age address table faster. After an
age cycle is complete, the age logic will return to
normal (300 +/- 75 seconds).
Note: If any port is unplugged, all addresses will be
automatically aged out.
R/W
0
Register 3 (0x03): Global Control 1
7
Pass All Frames
1, switch all packets including bad ones. Used solely
for debugging purpose. Works in conjunction with
sniffer mode.
R/W
0
6
2K Byte packet support
1 = enable support 2K Byte packet
0 = disable support 2K Byte packet
R/W
0
5
IEEE 802.3x Transmit
Flow Control Disable
0, will enable transmit flow control based on AN result.
1, will not enable transmit flow control regardless of
AN result.
R/W
0
Pin PMRXD3
strap option.
PD(0): Enable Tx
flow control
(default).
PU(1): Disable
Tx/Rx flow
control.
Note: PMRXD3
has internal
pull-down.
4
IEEE 802.3x Receive
Flow Control Disable
0, will enable receive flow control based on AN result.
1, will not enable receive flow control regardless of AN
result.
Note: Bit 5 and bit 4 default values are controlled by the same
pin, but they can be programmed independently.
R/W
0
Pin PMRXD3
strap option.
PD (0): Enable
Rx flow control
(default).
PU(1): Disable
Tx/Rx flow
control.
Note: PMRXD3
has internal
pull-down.
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Global Registers (Continued)
Address
Name
Description
Mode
Default
3
Frame Length Field
Check
1, will check frame length field in the IEEE packets
If the actual length does not match, the packet will be
dropped (for L/T <1500).
R/W
0
2
Aging Enable
1, Enable age function in the chip.
0, Disable aging function.
R/W
1
Pin LED[5][2]
strap option.
PD(0): Aging
disable.
PU(1): Aging
enable (default).
Note: LED[5][2]
has internal pull
up.
1
Fast age Enable
1 = Turn on fast age (800µs).
R/W
0
0
Aggressive Back Off
Enable
1 = Enable more aggressive back-off algorithm in half
duplex mode to enhance performance. This is not an
IEEE standard.
R/W
0
Pin PMRXD0
strap option.
PD(0): Disable
aggressive back
off (default).
PU(1):
Aggressive back
off.
Note: PMRXD0
has internal pull
down.
Register 4 (0x04): Global Control 2
7
Unicast Port-VLAN
Mismatch Discard
This feature is used for port VLAN (described in
Register 17, Register 33...).
1, all packets cannot cross VLAN boundary.
0, unicast packets (excluding unknown/
multicast/broadcast) can cross VLAN boundary.
R/W
1
6
Multicast Storm
Protection Disable
1, “Broadcast Storm Protection” does not include
multicast packets. Only DA = FFFFFFFFFFFF packets
will be regulated.
0, “Broadcast Storm Protection” includes
DA = FFFFFFFFFFFF and DA[40] = 1 packet.
R/W
1
5
Back Pressure Mode
1, carrier sense based backpressure is selected.
0, collision based backpressure is selected.
R/W
1
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Global Registers (Continued)
Address
Name
Description
Mode
Default
4
Flow Control and Back
Pressure fair Mode
1, fair mode is selected. In this mode, if a flow control
port and a non-flow control port talk to the same
destination port, then packets from the non-flow control
port may be dropped. This is to prevent the flow control
port from being flow controlled for an extended period of
time.
0, in this mode, if a flow control port and a non-flow
control port talk to the same destination port, the flow
control port will be flow controlled. This may not be “fair”
to the flow control port.
R/W
1
3
No Excessive Collision
Drop
1, the switch will not drop packets when 16 or more
collisions occur.
0, the switch will drop packets when 16 or more
collisions occur.
R/W
0
Pin PMRXD1 strap
option.
PD(0): (default ) Drop
excessive collision
packets. PU(1): Do
Not drop excessive
collision packets.
Note: PMRXD1 has
internal pull-down.
2
Huge Packet Support
1, will accept packet sizes up to 1916 bytes (inclusive).
This bit setting will override setting from bit 1 of the
same register.
0, the max packet size will be determined by bit 1 of this
register.
R/W
0
1
Legal Maximum Packet
Size Check Disable
1, will accept packet sizes up to 1536 bytes (inclusive).
0, 1522 bytes for tagged packets (not including packets
with STPID from CPU to ports 1-4), 1518 bytes for
untagged packets. Any packets larger than the
specified value will be dropped.
R/W
0
Pin PMRXER strap
option.
PD(0): (default)
1518/1522 byte
packets.
PU(1): 1536 byte
packets.
Note: PMRXER has
internal pull-down.
0
Reserved
N/A
RO
0
Register 5 (0x05): Global Control 3
7
802.1q VLAN Enable
1, 802.1q VLAN mode is turned on. VLAN table needs
to set up before the operation.
0, 802.1q VLAN is disabled.
R/W
0
6
IGMP Snoop Enable
on Switch SW5-
MII/RMII Interface
1, IGMP snoop enabled. All the IGMP packets will be
forwarded to Switch MII/RMII port.
0, IGMP snoop disabled.
R/W
0
5
Enable Direct Mode on
Switch SW5-MII/RMII
Interface
1, direct mode on Port 5. This is a special mode for the
Switch MII/RMII interface. Using preamble before
MRXDV to direct switch to forward packets, bypassing
internal look-up.
0, normal operation.
R/W
0
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Global Registers (Continued)
Address
Name
Description
Mode
Default
4
Enable Pre-Tag on
Switch SW5-MII/RMIII
Interface
1, packets forwarded to Switch MII/RMII interface will
be pre-tagged with the source port number (preamble
before MRXDV).
0, normal operation.
R/W
0
3-2
Reserved
N/A
RO
00
1
Enable “Tag” Mask
1, the last 5 digits in the VID field are used as a mask to
determine which port(s) the packet should be forwarded
to.
0, no tag masks.
Note: you need to turn off the 802.1q VLAN mode (reg0x5, bit
7 = 0) for this bit to work
R/W
0
0
Sniff Mode Select
1, will do Rx AND Tx sniff (both source port and
destination port need to match).
0, will do Rx OR Tx sniff (Either source port or
destination port needs to match).
This is the mode used to implement Rx only sniff.
R/W
0
Register 6 (0x06): Global Control 4
7
Switch SW5-MII/RMII
Back Pressure Enable
1, enable half-duplex back pressure on switch MII/RMII
interface.
0, disable back pressure on switch MII interface.
R/W
0
6
Switch SW5-MII/RMII
Half-Duplex Mode
1, enable MII/RMII interface half-duplex mode.
0, enable MII/RMII interface full-duplex mode.
R/W
0
Pin SMRXD2
strap option.
PD(0): (default)
Full-duplex
mode.
PU(1): Half-
duplex mode.
Note: SMRXD2
has internal
pull-down.
5
Switch SW5-MII/RMII
Flow Control Enable
1, enable full-duplex flow control on switch MII/RMII
interface.
0, disable full-duplex flow control on switch MII/RMII
interface.
R/W
0
Pin SMRXD3
strap option.
PD(0): (default)
Disable flow
control.
PU(1): enable
flow control.
Note: SMRXD3
has internal
pull-down.
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Global Registers (Continued)
Address
Name
Description
Mode
Default
4
Switch SW5-MII/RMII
Speed
1, the switch SW5-MII/RMII is in 10Mbps mode.
0, the switch SW5-MII/RMII is in 100Mbps mode.
R/W
0
Pin SMRXD1
strap option.
PD(0): (default)
Enable 100Mbps.
PU(1): Enable
10Mbps.
Note: SMRXD1
has internal
pull-down.
3
Null VID Replacement
1, will replace null VID with port VID (12 bits).
0, no replacement for null VID.
R/W
0
2-0
Broadcast Storm
Protection Rate Bit[10:8]
This along with the next register determines how many
“64 byte blocks” of packet data allowed on an input port
in a preset period. The period is 50ms for 100BT or
500ms for 10BT. The default is 1%.
R/W
000
Register 7 (0x07): Global Control 5
7-0
Broadcast Storm
Protection Rate Bit[7:0]
This along with the previous register determines how
many “64-byte blocks” of packet data are allowed on an
input port in a preset period. The period is 50ms for
100BT or 500ms for 10BT. The default is 1%.
R/W
0x4A(1)
Register 8 (0x08): Global Control 6
7-0
Factory Testing
N/A, do not change
RO
0x00
Register 9 (0x09): Global Control 7
7-0
Factory Testing
N/A, do not change
RO
0x4C
Note:
7. 148,800 frames/sec × 50ms/interval × 1% = 74 frames/interval (approx.) = 0x4A.
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Global Registers (Continued)
Address
Name
Description
Mode
Default
Register 10 (0x0A): Global Control 8
7-0
Factory Testing
N/A, do not change
RO
0x00
Register 11 (0x0B): Global Control 9
7
Reversed
N/A, do not change
RO
0
6
Port 5 SW5- RMII
reference clock edge
select
RQX: Select the data sampling edge of Switch MAC5
SW5- RMII reference clock:
1 = data sampling on negative edge of refclk
0 = data sampling on positive edge of refclk (default)
Note: MQX/FQX/ML is reserved with read only for this bit.
R/W
0
5
Reserved
N/A, do not change
RO
0
4
Reserved
N/A, do not change
RO
0
3
PHY Power
Save
1 = disable PHY power save mode.
0 = enable PHY power save mode.
R/W
0
2
Reserved
N/A, do not change
RO
0
1
LED Mode
0 = led mode 0.
1 = led mode 1.
Mode 0, link at
100/Full LEDx[2,1,0] = 0,0,0
100/Half LEDx[2,1,0] = 0,1,0
10/Full LEDx[2,1,0] = 0,0,1
10/Half LEDx[2,1,0] = 0,1,1
Mode 1, link at
100/Full LEDx[2,1,0] = 0,1,0
100/Half LEDx[2,1,0] = 0,1,1
10/Full LEDx[2,1,0] = 1,0,0
10/Half LEDx[2,1,0] = 1,0,1
(0 = LED on, 1 = LED off)
R/W
0
Pin SMRXD0 –
strap option.
Pull-down(0):
Enabled led
mode 0.
Pull-up(1):
Enabled led
mode 1.
Note: SMRXD0
has internal
pull-down 0.
Mode 0
Mode 1
LEDX_2
Lnk/Act
100Lnk/Act
LEDX_1
Fulld/Col
10Lnk/Act
LEDX_0
Speed
Fulld
0
SPI/SMI read sampling
clock edge select
Select the SPI/SMI clock edge for sampling SPI/SMI
read data.
1 = trigger by rising edge of SPI/SMI clock (for high
speed SPI about 25MHz and SMI about 10MHz)
0 = trigger by falling edge of SPI/SMI clock.
R/W
0
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Global Registers (Continued)
Address
Name
Description
Mode
Default
Register 12 (0x0C): Global Control 10
7
Reserved
Reserved
RO
0
6
Status of device with RMII
interface at clock mode or
normal mode, default is
clock mode with 25MHz
Crystal clock from pins
X1/X2
(used for RMII of the
KSZ8895RQX only)
1 = The device is in clock mode when use RMII
interface, 25 MHz Crystal clock input as clock source
for internal PLL. This internal PLL will provide the 50
MHz output on the pin SMRXC for RMII reference
clock (Default).
0 = The device is in normal mode when use SW4-RMII
interface and 50 MHz clock input from external clock
through pin SM4TXC as device’s clock source and
internal PLL clock source from this pin not from the
25MHz crystal.
Note: This bit is set by strap option only. Write to this bit has
no effect on mode selection.
Note: The normal mode is used in SW5-RMII interface
reference clock from external.
RO
1
Pin LED[2][2]
strap option.
PD(0): Select
SW5-RMII at
normal mode to
receive external
50MHz RMII
reference clock
PU(1): (default)
Select SW5-
RMII at clock
mode, RMII
output 50MHz
Note: LED[2][2]
has internal
pull-up.
5 – 4
CPU interface clock select
Select the internal clock speed for SPI, MDI interface:
00 = 41.67MHz (SPI up to 6.25MHz, MDC up to
6MHz)
01 = 83.33MHz Default (SPI SCL up to 12.5MHz,
MDC up to 12MHz)
10 = 125MHz (for high speed SPI about 25MHz)
11 = Reserved
R/W
01
3
Reserved
N/A, do not change
RO
0
2
Enable restore preamble
This bit is to enable PHY5, when in 10BT mode, to
restore preamble before sending data on P5-MII
interface.
1 = Enable PHY5 to restore preamble.
0 = Disable PHY5 to restore preamble.
R/W
1
1
Tail Tag Enable
Tail Tag feature is applied for Port 5 only.
1 = Insert 1 Byte of data right before FCS.
0 = Do not insert.
R/W
0
0
Pass Flow Control Packet
1 = Switch will not filter 802.1x “flow control” packets.
0 = Switch will filter 802.1x “flow control” packets.
R/W
0
Register 13 (0x0D): Global Control 11
7 – 0
Factory Testing
N/A, do not change
RO
00000000
Register 14 (0x0E): Power Down Management Control 1
7
Reserved
N/A, do not change
RO
0
6
Reserved
N/A, do not change
RO
0
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Global Registers (Continued)
Address
Name
Description
Mode
Default
5
PLL Power Down
Pll power down enable:
1 = Enable
0 = Disable
R/W
0
4 – 3
Power Management Mode
Power management mode :
00 = Normal mode (D0)
01 = Energy Detection mode (D2)
10 = soft Power Down mode (D3)
11 = Power Saving mode (D1)
R/W
00
Pin LED[4][0]
strap option.
PD(0): Select
Energy detection
mode
PU(1): (default)
Normal mode
Note: LED[4][0]
has internal
pull-up.
2-0
Reserved
N/A, do not change
RO
000
Register 15 (0x0F): Power Down Management Control 2
7 – 0
Go_sleep_time[7:0]
When the Energy Detect mode is on, 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. The unit is 20ms.
The default of go_sleep time is 1.6 seconds (80Dec x
20ms).
R/W
01010000
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Port Registers
The following registers are used to enable features that are assigned on a per port basis. The register bit
assignments are the same for all ports, but the address for each port is different, as indicated.
Register 16 (0x10): Port 1 Control 0
Register 32 (0x20): Port 2 Control 0
Register 48 (0x30): Port 3 Control 0
Register 64 (0x40): Port 4 Control 0
Register 80 (0x50): Port 5 Control 0
Address
Name
Description
Mode
Default
7
Broadcast Storm
Protection Enable
1, enable broadcast storm protection for ingress
packets on the port.
0, disable broadcast storm protection.
R/W
0
6
DiffServ Priority
Classification Enable
1, enable DiffServ priority classification for ingress
packets on port.
0, disable DiffServ function.
R/W
0
5
802.1p Priority
Classification Enable
1, enable 802.1p priority classification for ingress
packets on port.
0, disable 802.1p.
R/W
0
4 – 3
Port-Based Priority
Classification Enable
= 00, ingress packets on port will be
classified as priority 0 queue if “Diffserv” or “802.1p”
classification is not enabled or fails to classify.
= 01, ingress packets on port will be
classified as priority 1 queue if “Diffserv” or “802.1p”
classification is not enabled or fails to classify.
= 10, ingress packets on port will be
classified as priority 2 queue if “Diffserv” or “802.1p”
classification is not enabled or fails to classify.
= 11, ingress packets on port will be
classified as priority 3 queue if “Diffserv” or “802.1p”
classification is not enabled or fails to classify.
Note: “DiffServ”, “802.1p” and port priority can be
enabled at the same time. The OR’ed result of 802.1p
and DSCP overwrites the port priority.
R/W
00
2
Tag insertion
1, when packets are output on the port, the switch will
add 802.1q tags to packets without 802.1q tags when
received. The switch will not add tags to packets
already tagged. The tag inserted is the ingress port’s
“port VID.”
0, disable tag insertion.
R/W
0
1
Tag Removal
1, when packets are output on the port, the switch will
remove 802.1q tags from packets with 802.1q tags
when received. The switch will not modify packets
received without tags.
0, disable tag removal.
R/W
0
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Port Registers (Continued)
Address
Name
Description
Mode
Default
0
Two Queues Split Enable
This bit 0 in the Register16/32/48/64/80 should be in
combination with Register177/193/209/225/241 bit 1
for Port 1-5 will select the split of ½/4 queues:
For Port 1, [Register 177 bit 1, Register 16 bit 0] =
[11], Reserved
[10], the port output queue is split into four priority
queues or if map 802.1p to priority 0-3 mode.
[01], the port output queue is split into two priority
queues or if map 802.1p to priority 0-3 mode.
[00], single output queue on the port. There is no
priority differentiation even though packets are
classified into high or low priority.
R/W
0
Register 17 (0x11): Port 1 Control 1
Register 33 (0x21): Port 2 Control 1
Register 49 (0x31): Port 3 Control 1
Register 65 (0x41): Port 4 Control 1
Register 81 (0x51): Port 5 Control 1
Address
Name
Description
Mode
Default
7
Sniffer Port
1, port is designated as sniffer port and will transmit
packets that are monitored.
0, port is a normal port.
R/W
0
6
Receive Sniff
1, all the packets received on the port will be marked
as “monitored packets” and forwarded to the
designated “sniffer port.”
0, no receive monitoring.
R/W
0
5
Transmit Sniff
1, all the packets transmitted on the port will be marked
as “monitored packets” and forwarded to the
designated “sniffer port.”
0, no transmit monitoring.
R/W
0
4-0
Port VLAN Membership
Define the port’s Port VLAN membership. Bit 4 stands
for Port 5, bit 3 for Port 4...bit 0 for Port 1. The port can
only communicate within the membership. A ‘1’
includes a port in the membership, a ‘0’ excludes a port
from membership.
R/W
0x1f
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Port Registers (Continued)
Register 18 (0x12): Port 1 Control 2
Register 34 (0x22): Port 2 Control 2
Register 50 (0x32): Port 3 Control 2
Register 66 (0x42): Port 4 Control 2
Register 82 (0x52): Port 5 Control 2
Address
Name
Description
Mode
Default
7
User Priority
Ceiling
1, If packet ‘s “user priority field” is greater than the
“user priority field” in the port default tag register,
replace the packet’s “user priority field” with the “user
priority field” in the port default tag Register control 3.
0, no replace packet’s priority filed with port default tag
priority filed of the Register Port Control 3 bit [7:5].
R/W
0
6
Ingress VLAN
Filtering.
1, the switch will discard packets whose VID port
membership in VLAN table bit [11:7] does not include
the ingress port.
0, no ingress VLAN filtering.
R/W
0
5
Discard Non-
PVID packets
1, the switch will discard packets whose VID does not
match ingress port default VID.
0, no packets will be discarded.
R/W
0
4
Force Flow
Control
1, will always enable Rx and Tx flow control on the port,
regardless of AN result.
0, the flow control is enabled based on AN result
(Default)
R/W
0
Strap-in option
LED1_1/PCOL For port
3/port 4 LED1_1 default Pull
up (1): Not force flow
control;
PCOL default Pull-down (0):
Not force flow control.
LED1_1 Pull down (0):
Force flow control; PCOL
Pull-up (1): Force flow
control.
Note: LED1_1 has internal
pull-up; PCOL have internal
pull-down.
3
Back Pressure
Enable
1, enable port half-duplex back pressure.
0, disable port half-duplex back pressure.
R/W
Pin PMRXD2 strap option.
Pull-down (0): disable back
pressure.
Pull-up(1): enable back
pressure.
Note: PMRXD2 has internal
pull-down.
2
Transmit Enable
1, enable packet transmission on the port.
0, disable packet transmission on the port.
R/W
1
1
Receive Enable
1, enable packet reception on the port.
0, disable packet reception on the port.
R/W
1
0
Learning Disable
1, disable switch address learning capability.
0, enable switch address learning.
R/W
0
Note: Bits 2-0 are used for spanning tree support. See “Spanning Tree Support” section.
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Port Registers (Continued)
Register 19 (0x13): Port 1 Control 3
Register 35 (0x23): Port 2 Control 3
Register 51 (0x33): Port 3 Control 3
Register 67 (0x43): Port 4 Control 3
Register 83 (0x53): Port 5 Control 3
Address
Name
Description
Mode
Default
7-0
Default Tag [15:8]
Port’s default tag, containing:
7-5: user priority bits
4: CFI bit
3-0 : VID[11:8]
R/W
0
Register 20 (0x14): Port 1 Control 4
Register 36 (0x24): Port 2 Control 4
Register 52 (0x34): Port 3 Control 4
Register 68 (0x44): Port 4 Control 4
Register 84 (0x54): Port 5 Control 4
Address
Name
Description
Mode
Default
7-0
Default Tag [7:0]
Default port 1’s tag, containing:
7-0: VID[7:0]
R/W
1
Note: Registers 19 and 20 (and those corresponding to other ports) serve two purposes: (1) Associated with the ingress untagged packets, and
used for egress tagging; (2) Default VID for the ingress untagged or null-VID-tagged packets, and used for address look up.
Register 87 (0x57): RMII Management Control Register
Address
Name
Description
Mode
Default
7 - 4
Reserved
N/A, do not change
RO
0000
3
Port 5 SW5-RMII 50MHz
clock output disable
(used for KSZ8895RQX
only)
Disable the output of port 5 SW5-RMII 50 MHz output
clock on RXC pin when 50MHz clock is not being used
by the device and the 50MHz clock from external
oscillator or opposite device in RMII mode
1 = Disable clock output when RXC pin is not used in
RMII mode
0 = Enable clock output in RMII mode
Note: MQX/FQX/ML is reserved with read only for this bit.
R/W
0
2
P5-RMII 50MHz clock
output disable
(used for KSZ8895RQX
only)
Disable the output of port 5 P5-RMII 50 MHz output
clock on RXC pin when 50MHz clock is not being used
by the device and the 50MHz clock from external
oscillator or opposite device in RMII mode
1 = Disable clock output when RXC pin is not used in
RMII mode
0 = Enable clock output in RMII mode
Note: MQX/FQX/ML is reserved with read only for this bit.
R/W
0
1 - 0
Reserved
N/A, do not change
RO
00
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Port Registers (Continued)
Register 25 (0x19): Port 1 Status 0
Register 41 (0x29): Port 2 Status 0
Register 57 (0x39): Port 3 Status 0
Register 73 (0x49): Port 4 Status 0
Register 89 (0x59): Port 5 Status 0
Address
Name
Description
Mode
Default
7
Hp_mdix
1 = HP Auto MDI/MDI-X mode
0 = Micrel Auto MDI/MDI-X mode
R/W
1
6
Factory Testing
N/A, do not change
RO
0
5
Polrvs
1 = Polarity is reversed
0 = Polarity is not reversed
RO
0
4
Transmit Flow Control
Enable
1 = Transmit flow control feature is active
0 = Transmit flow control feature is inactive
RO
0
3
Receive Flow Control
Enable
1 = Receive flow control feature is active
0 = Receive flow control feature is inactive
RO
0
2
Operation Speed
1 = Link speed is 100Mbps
0 = Link speed is 10Mbps
RO
0
1
Operation Duplex
1 = Link duplex is full
0 = Link duplex is half
RO
0
0
Reserved
N/A, do not change
RO
0
Register 26 (0x1A): Port 1 PHY Special Control/Status
Register 42 (0x2A): Port 2 PHY Special Control/Status
Register 58 (0x3A): Port 3 PHY Special Control/Status
Register 74 (0x4A): Port 4 PHY Special Control/Status
Register 90 (0x5A): Port 5 PHY Special Control/Status
Address
Name
Description
Mode
Default
7
Vct 10M Short
1 = less than 10 meter short detected
RO
0
6 - 5
Vct_result
00 = Normal condition
01 = Open condition detected in cable
10 = Short condition detected in cable
11 = Cable diagnostic test has failed
RO
00
4
Vct_enable
1 = Enable cable diagnostic test. After VCT test has
completed, this bit will be self-cleared.
0 = Indicate cable diagnostic test (if enabled) has
completed and the status information is valid for read.
R/W
(SC)
0
3
Force_lnk
1 = Force link pass
0 = Normal Operation
R/W
0
2
Pwrsave
1 = Enable power saving
0 = Disable power saving
R/W
0
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1
Remote Loopback
1 = Perform Remote loopback, loopback on port 1 as
follows:
Port 1 (reg. 26, bit 1 = ‘1’)
Start : RXP1/RXM1 (port 1)
Loopback: PMD/PMA of port 1’s PHY
End: TXP1/TXM1 (port 1)
Setting reg. 42, 58, 74, 90, bit 1 = ‘1’ will perform
remote loopback on port 2, 3, 4, 5.
0 = Normal Operation.
R/W
0
0
Vct_fault_count[8]
Bits[8] of VCT fault count
Distance to the fault.
It’s approximately 0.4m*Vct_fault_count[8:0]
RO
0
Register 27 (0x1B): Port 1 LinkMD result
Register 43 (0x2B): Port 2 LinkMD result
Register 59 (0x3B): Port 3 LinkMD result
Register 75 (0x4B): Port 4 LinkMD result
Register 91 (0x5B): Port 5 LinkMD result
Address
Name
Description
Mode
Default
7-0
Vct_fault_count[7:0]
Bits[7:0] of VCT fault count
Distance to the fault.
It’s approximately 0.4m*Vct_fault_count[8:0]
RO
0
Register 28 (0x1C): Port 1 Control 5
Register 44 (0x2C): Port 2 Control 5
Register 60 (0x3C): Port 3 Control 5
Register 76 (0x4C): Port 4 Control 5
Register 92 (0x5C): Port 5 Control 5
Address
Name
Description
Mode
Default
7
Disable Auto-Negotiation
1, disable auto-negotiation, speed and duplex are
decided by bit 6 and 5 of the same register.
0, auto-negotiation is on.
Note: The register bit value is the INVERT of the strap
value at the pin.
R/W
0
For Port 3/Port 4
only. INVERT of
pins
LED[2][1]/LED[5][0]
strap option.
PD(0): Disable Auto-
Negotiation.
PU(1): Enable Auto-
Negotiation.
Note:
LED[2][1]/LED[5][0]
have internal pull
up.
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Revision-1.1
Port Registers (Continued)
Address
Name
Description
Mode
Default
6
Forced Speed
1, forced 100BT if AN is disabled (bit 7).
0, forced 10BT if AN is disabled (bit 7).
R/W
1
5
Forced Duplex
1, forced full-duplex if (1) AN is disabled or (2) AN is
enabled but failed.
0, forced half-duplex if (1) AN is disabled or (2) AN is
enabled but failed (Default).
R/W
0
For Port 3/Port 4
only. Pins
LED1_0/PCRS strap
option:
1). Force half-duplex
mode:
LED1_0 pin Pull-
up(1) (default) for
Port 3
PCRS pin Pull-down
(0) (default) for Port
4
2). Force full-Duplex
mode:
LED1_0 pin Pull-
down(0) for Port 3
PCRS Pull-up (1) for
Port 4.
Note: LED1_0 has
internal pull-up;
PCRS have
internal pull down.
4
Advertised Flow Control
Capability
1, advertise flow control capability.
0, suppress flow control capability from transmission
to link partner.
R/W
1
3
Advertised 100BT Full-
Duplex Capability
1, advertise 100BT full-duplex capability.
0, suppress 100BT full-duplex capability from
transmission to link partner.
R/W
1
2
Advertised 100BT Half-
Duplex Capability
1, advertise 100BT half-duplex capability.
0, suppress 100BT half-duplex capability from
transmission to link partner.
R/W
1
1
Advertised 10BT Full-
Duplex Capability
1, advertise 10BT full-duplex capability.
0, suppress 10BT full-duplex capability from
transmission to link partner.
R/W
1
0
Advertised 10BT Half-
Duplex Capability
1, advertise 10BT half-duplex capability.
0, suppress 10BT half-duplex capability from
transmission to link partner.
R/W
1
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Register 29 (0x1D): Port 1 Control 6
Register 45 (0x2D): Port 2 Control 6
Register 61 (0x3D): Port 3 Control 6
Register 77 (0x4D): Port 4 Control 6
Register 93 (0x5D): Port 5 Control 6
Address
Name
Description
Mode
Default
7
LED Off
1, turn off all port’s LEDs (LEDx_2, LEDx_1, LEDx_0,
where “x” is the port number). These pins will be driven
high if this bit is set to one.
0, normal operation.
R/W
0
6
Txids
1, disable port’s transmitter.
0, normal operation.
R/W
0
5
Restart AN
1, restart auto-negotiation.
0, normal operation.
R/W
(SC)
0
4
FX reserved
N/A
RO
0
3
Power Down
1, power down.
0, normal operation.
R/W
0
2
Disable Auto MDI/MDI-X
1, disable auto MDI/MDI-X function.
0, enable auto MDI/MDI-X function.
R/W
0
1
Forced MDI
1, if auto MDI/MDI-X is disabled, force PHY into MDI
mode (transmit on RX pair).
0, MDI-X mode (transmit on TX pair).
R/W
0
0
MAC Loopback
1 = Perform MAC loopback, loop back path as follows:
E.g. set port 1 MAC Loopback (reg. 29, bit 0 = ‘1’), use
port 2 as monitor port. The packets will transfer
Start: Port 2 receiving (also can start to receive
packets from port 3, 4, 5).
Loop-back: Port 1’s MAC.
End: Port 2 transmitting (also can end at Port 3, 4,
5 respectively).
Setting reg. 45, 61, 77, 93, bit 0 = ‘1’ will perform MAC
loopback on port 2, 3, 4, 5 respectively.
0 = Normal Operation.
R/W
0
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Port Registers (Continued)
Register 30 (0x1E): Port 1 Status 1
Register 46 (0x2E): Port 2 Status 1
Register 62 (0x3E): Port 3 Status 1
Register 78 (0x4E): Port 4 Status 1
Register 94 (0x5E): Port 5 Status 1
Address
Name
Description
Mode
Default
7
MDIX Status
1, MDI.
0, MDI-X.
RO
0
6
AN Done
1, AN done.
0, AN not done.
RO
0
5
Link Good
1, link good.
0, link not good.
RO
0
4
Partner Flow Control
Capability
1, link partner flow control capable.
0, link partner not flow control capable.
RO
0
3
Partner 100BT Full-
Duplex Capability
1, link partner 100BT full-duplex capable.
0, link partner not 100BT full-duplex capable.
RO
0
2
Partner 100BT Half-
Duplex Capability
1, link partner 100BT half-duplex capable.
0, link partner not 100BT half-duplex capable.
RO
0
1
Partner 10BT Full-Duplex
Capability
1, link partner 10BT full-duplex capable.
0, link partner not 10BT full-duplex capable.
RO
0
0
Partner 10BT Half-Duplex
Capability
1, link partner 10BT half-duplex capable.
0, link partner not 10BT half-duplex capable.
RO
0
Register 31 (0x1F): Port 1 Control 7 and Status 2
Register 47 (0x2F): Port 2 Control 7 and Status 2
Register 63 (0x3F): Port 3 Control 7 and Status 2
Register 79 (0x4F): Port 4 Control 7 and Status 2
Register 95 (0x5F): Port 5 Control 7 and Status 2
Address
Name
Description
Mode
Default
7
PHY Loopback
1 = Perform PHY loopback, loop back path as follows:
E.g. set port 1 PHY Loopback (reg. 31, bit 7 = ‘1’)
Use the port 2 as monitor port. The packets will
transfer.
Start: Port 2 receiving (also can start from port
3, 4, 5).
Loopback: PMD/PMA of Port 1’s PHY
End: Port 2 transmitting (also can end at Port 3,
4, 5 respectively).
Setting reg. 47, 63, 79, 95, bit 7 = ‘1’ will perform
PHY loopback on port 2, 3, 4, 5 respectively.
0 = Normal Operation.
R/W
0
6
Reserved
RO
0
5
PHY Isolate
1, Electrical isolation of PHY from MII/RMII and
TX+/TX-.
0, normal operation.
R/W
0
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4
Soft Reset
1, PHY soft reset. This bit is self-clear.
0, normal operation.
R/W
(SC)
0
3
Force Link
1, force link in the PHY.
0, normal operation
R/W
0
2-0
Port Operation Mode
Indication
Indicate the current state of port operation mode:
[000] = Reserved
[001] = still in auto-negotiation
[010] = 10BASE-T half duplex
[011] = 100BASE-TX half duplex
[100] = Reserved
[101] = 10BASE-T full duplex
[110] = 100BASE-TX full duplex
[111] = Reserved
RO
001
Note:
Port Control 12 and 13, 14 and Port Status 1,2 contents can be accessed by MIIM (MDC/MDIO) interface via the standard MIIM register definition.
Advanced Control Registers
Registers 104 to 109 define the switching engine’s MAC address. This 48-bit address is used as the source address in MAC
pause control frames.
Address
Name
Description
Mode
Default
Register 104 (0x68): MAC Address Register 0
7-0
MACA[47:40]
R/W
0x00
Register 105 (0x69): MAC Address Register 1
7-0
MACA[39:32]
R/W
0x10
Register 106 (0x6A): MAC Address Register 2
7-0
MACA[31:24]
R/W
0xA1
Register 107 (0x6B): MAC Address Register 3
7-0
MACA[23:16]
R/W
0xff
Register 108 (0x6C): MAC Address Register 4
7-0
MACA[15:8]
R/W
0xff
Register 109 (0X6D): MAC Address Register 5
7-0
MACA[7:0]
R/W
0xff
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Note: Use Registers 110 and 111 to read or write data to the static MAC address table, VLAN table, dynamic address table, or the MIB counters.
Address
Name
Description
Mode
Default
Register 110 (0x6E): Indirect Access Control 0
7-5
Reserved
Reserved.
R/W
000
4
Read High Write Low
1, read cycle.
0, write cycle.
R/W
0
3-2
Table Select
00 = static mac address table selected.
01 = VLAN table selected.
10 = dynamic address table selected.
11 = MIB counter selected.
R/W
0
1-0
Indirect Address High
Bit 9-8 of indirect address.
R/W
00
Address
Name
Description
Mode
Default
Register 111 (0x6F): Indirect Access Control 1
7-0
Indirect Address Low
Bit 7-0 of indirect address.
R/W
00000000
Note: Write to Register 111 will actually trigger a command. Read or write access will be decided by bit 4 of Register 110.
Address
Name
Description
Mode
Default
Register 112 (0x70): Indirect Data Register 8
68-64
Indirect Data
Bit 68-64 of indirect data.
R/W
00000
Register 113 (0x71): Indirect Data Register 7
63-56
Indirect Data
Bit 63-56 of indirect data.
R/W
00000000
Register 114 (0x72): Indirect Data Register 6
55-48
Indirect Data
Bit 55-48 of indirect data.
R/W
00000000
Register 115 (0x73): Indirect Data Register 5
47-40
Indirect Data
Bit 47-40 of indirect data.
R/W
00000000
Register 116 (0x74): Indirect Data Register 4
39-32
Indirect Data
Bit 39-32 of indirect data.
R/W
00000000
Register 117 (0x75): Indirect Data Register 3
31-24
Indirect Data
Bit of 31-24 of indirect data
R/W
00000000
Register 118 (0x76): Indirect Data Register 2
23-16
Indirect Data
Bit 23-16 of indirect data.
R/W
00000000
Register 119 (0x77): Indirect Data Register 1
15-8
Indirect Data
Bit 15-8 of indirect data.
R/W
00000000
Register 120 (0x78): Indirect Data Register 0
7-0
Indirect Data
Bit 7-0 of indirect data.
R/W
00000000
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 124 (0x7C): Interrupt Status Register
7 – 5
Reserved
Reserved.
RO
000
4
Port 5 Interrupt Status
1, Port 5 interrupt request
0, normal
Note: This bit is set by Port 5 link change. Write a “1” to
clear this bit
RO
0
3
Port 4 Interrupt Status
1, Port 4 interrupt request
0, normal
Note: This bit is set by Port 4 link change. Write a “1” to
clear this bit
RO
0
2
Port 3 Interrupt Status
1, Port 3 interrupt request
0, normal
Note: This bit is set by Port 3 link change. Write a “1” to
clear this bit
RO
0
1
Port 2 Interrupt Status
1, Port 2 interrupt request
0, normal
Note: This bit is set by Port 2 link change. Write a “1” to
clear this bit
RO
0
0
Port 1 Interrupt Status
1, Port 1 interrupt request
0, normal
Note: This bit is set by Port 1 link change. Write a “1” to
clear this bit
RO
0
Register 125 (0x7D): Interrupt Mask Register
7 – 5
Reserved
Reserved.
RO
000
4
Port 5 Interrupt Mask
1, Enable Port 5 interrupt.
0, normal
R/W
0
3
Port 4 Interrupt Mask
1, Enable Port 4 interrupt.
0, normal
R/W
0
2
Port 3 Interrupt Mask
1, Enable Port 3 interrupt.
0, normal
R/W
0
1
Port 2 Interrupt Mask
1, Enable Port 2 interrupt.
0, normal
R/W
0
0
Port 1 Interrupt Mask
1, Enable Port 1 interrupt.
0, normal
R/W
0
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Advanced Control Registers (Continued)
The Registers 128, 129 can be used to map from 802.1p priority field 0-7 to switch’s four priority queues 0-3, 0x3 is highest priority
queues as priority 3, 0x0 is lowest priority queues as priority 0.
Address
Name
Description
Mode
Default
Register 128 (0x80): Global Control 12
7 – 6
Tag_0x3
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x3.
R/W
0x1
5 – 4
Tag_0x2
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x2.
R/W
0x1
3 – 2
Tag_0x1
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x1.
R/W
0x0
1 – 0
Tag_0x0
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x0.
R/W
0x0
Register 129 (0x81): Global Control 13
7 – 6
Tag_0x7
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x7.
R/W
0x3
5 – 4
Tag_0x6
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x6.
R/W
0x3
3 – 2
Tag_0x5
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x5.
R/W
0x2
1 – 0
Tag_0x4
IEEE 802.1p mapping. The value in this field is
used as the frame’s priority when its IEEE 802.1p
tag has a value of 0x4.
R/W
0x2
Register 130 (0x82): Global Control 14
7 – 6
Pri_2Q[1:0]
(Note that program
Prio_2Q[1:0] = 01 is not
supported and should be
avoided)
When the 2 Queues configuration is selected, these
Pri_2Q[1:0] bits are used to map the 2-bit result of
IEEE 802.1p from Register 128/129 or
TOS/DiffServ from Register 144- 159 mapping (for
4 Queues) into two queues low/high priorities.
2-bit result of IEEE 802.1p or TOS/DiffServ
00 (0) = map to Low priority queue
01 (1) = Prio_2Q[0] map to Low/High priority queue
10 (2) = Prio_2Q[1] map to Low/High priority queue
11 (3) = map to High priority queue
Pri_2Q[1:0] =
00: Result 0,1,2 are low priority. 3 is high priority.
10: Result 0,1 are low priority. 2,3 are high priority
(default).
11: Result 0 is low priority. 1,2,3 are high priority.
R/W
10
5
Reserved
N/A, do not change
RO
0
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Address
Name
Description
Mode
Default
4
Reserved
N/A, do not change
RO
0
3 – 2
Reserved
N/A, do not change
RO
01
1
Reserved
N/A, do not change
RO
0
0
Reserved
N/A, do not change
RO
0
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 131 (0x83): Global Control 15
7
Reserved
N/A
RO
1
6
Reserved
N/A
RO
0
5
Unknown unicast packet
forward
1 = enable supporting unknown unicast packet
forward
0 = disable
R/W
0
4 – 0
Unknown unicast packet
forward port map
00000 = filter unknown unicast packet
00001 = forward unknown unicast packet to port 1
00011 = forward unknown unicast packet to port 1,
port 2
…
11111 = broadcast unknown unicast packet to all
ports
R/W
00000
Register 132 (0x84): Global Control 16
7 – 6
Chip I/O output drive strength
select[1:0]
Output drive strength select[1:0] =
00 = 4mA drive strength
01 = 8mA drive strength (default)
10 = 10mA drive strength
11 = 14mA drive strength
Note:
Bit [1] value is the INVERT of the strap value at the pin.
Bit[0] value is the SAME of the strap value at the pin
R/W
01
Pin LED[3][0]
strap option.
Pull-down (0):
Select 12mA
drive strength.
Pull-up (1):
Select 8mA
drive strength.
Note: LED[3][0]
has internal
pull-up.
5
Unknown multicast packet
forward (not including IP
multicast packet)
1 = enable supporting unknown multicast packet
forward
0 = disable
R/W
0
4 – 0
Unknown multicast packet
forward port map
00000 = filter unknown multicast packet
00001 = forward unknown multicast packet to port 1
00011 = forward unknown multicast packet to port
1, port 2
…
11111 = broadcast unknown multicast packet to all
ports
R/W
00000
Register 133(0x85): Global Control 17
7 – 6
Reserved
RO
00
5
Unknown VID packet forward
1 = enable supporting unknown VID packet forward
0 = disable
R/W
0
4 – 0
Unknown VID packet forward
port map
00000 = filter unknown VID packet
00001 = forward unknown VID packet to port 1
00011 = forward unknown VID packet to port 1,
port 2
…
11111 = broadcast unknown VID packet to all ports
R/W
00000
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 134 (0x86): Global Control 18
7
Reserved
N/A
RO
0
6
Self Address Filter Enable
1 = Enable filtering of self-address unicast and
multicast packet
0 = Do not filter self-address packet
Note: The self-address filtering will filter packets on the
egress port, self MAC address is assigned in the Register
104-109.
R/W
0
5
Unknown IP multicast packet
forward
1 = enable supporting unknown IP multicast packet
forward
0 = disable
R/W
0
4 – 0
Unknown IP multicast packet
forward port map
00000 = filter unknown IP multicast packet
00001 = forward unknown IP multicast packet to
port 1
00011 = forward unknown IP multicast packet to
port 1, port 2
…
11111 = broadcast unknown IP multicast packet to
all ports
R/W
00000
Register 135 (0x87): Global Control 19
7
Reserved
N/A, do not change
RO
0
6
Reserved
N/A, do not change
RO
0
5 – 4
Ingress Rate Limit Period
The unit period for calculating Ingress Rate Limit
00 = 16ms
01 = 64ms
1x = 256ms
R/W
01
3
Queue-based Egress Rate
Limit Enabled
Enable Queue-based Egress Rate Limit
0 = port-base Egress Rate Limit (default)
1 = queue-based Egress Rate Limit
R/W
0
2
Insertion Source Port PVID
Tag Selection Enable
1 = enable source port PVID tag insertion or non-
insertion option on the egress port for each source
port PVID based on the ports Registers control 8.
0 = disable, all packets from any ingress port will be
inserted PVID based on Register Port Control 0 bit
[2].
R/W
0
1 – 0
Reserved
N/A, do not change
RO
00
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 144 (0x90): TOS Priority Control Register 0
The Ipv4/Ipv6 TOS priority control registers implement a fully decoded 64 bit differentiated services code point (DSCP) register
used to determine priority from the 6 bit TOS field in the IP header. The most significant 6 bits of the TOS field are fully decoded
into 64 possibilities, and the singular code that results is mapped to the value in the corresponding bit in the DSCP register.
7 – 6
DSCP[7:6]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits [7:2] of the frame’s IP
TOS/DiffServ/Traffic Class value is 0x03
R/W
00
5 – 4
DSCP[5:4]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits [7:2] of the frame’s IP
TOS/DiffServ/Traffic Class value is 0x02
R/W
00
3 – 2
DSCP[3:2]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits [7:2] of the frame’s IP
TOS/DiffServ/Traffic Class value is 0x01
R/W
00
1 – 0
DSCP[1:0]
Ipv4 and Ipv6 mapping
The value in this field is used as the frame’s priority
when bits [7:2] of the frame’s IP
TOS/DiffServ/Traffic Class value is 0x00
R/W
00
Register 145 (0x91): TOS Priority Control Register 1
7 – 6
DSCP[15:14]
Ipv4 and Ipv6 mapping _ for value 0x07
R/W
00
5 – 4
DSCP[13:12]
Ipv4 and Ipv6 mapping _ for value 0x06
R/W
00
3 – 2
DSCP[11:10]
Ipv4 and Ipv6 mapping _ for value 0x05
R/W
00
1 – 0
DSCP[9:8]
Ipv4 and Ipv6 mapping _ for value 0x04
R/W
00
Register 146 (0x92): TOS Priority Control Register 2
7 – 6
DSCP[23:22]
Ipv4 and Ipv6 mapping _ for value 0x0B
R/W
00
5 – 4
DSCP[21:20]
Ipv4 and Ipv6 mapping _ for value 0x0A
R/W
00
3 – 2
DSCP[19:18]
Ipv4 and Ipv6 mapping _ for value 0x09
R/W
00
1 – 0
DSCP[17:16]
Ipv4 and Ipv6 mapping _ for value 0x08
R/W
00
Register 147 (0x93): TOS Priority Control Register 3
7 – 6
DSCP[31:30]
Ipv4 and Ipv6 mapping _ for value 0x0F
R/W
00
5 – 4
DSCP[29:28]
Ipv4 and Ipv6 mapping _ for value 0x0E
R/W
00
3 – 2
DSCP[27:26]
Ipv4 and Ipv6 mapping _ for value 0x0D
R/W
00
1 – 0
DSCP[25:24]
Ipv4 and Ipv6 mapping _ for value 0x0C
R/W
00
Register 148 (0x94): TOS Priority Control Register 4
7 – 6
DSCP[39:38]
Ipv4 and Ipv6 mapping _ for value 0x13
R/W
00
5 – 4
DSCP[37:36]
Ipv4 and Ipv6 mapping _ for value 0x12
R/W
00
3 – 2
DSCP[35:34]
Ipv4 and Ipv6 mapping _ for value 0x11
R/W
00
1 – 0
DSCP[33:32]
Ipv4 and Ipv6 mapping _ for value 0x10
R/W
00
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 149 (0x95): TOS Priority Control Register 5
7 – 6
DSCP[47:46]
Ipv4 and Ipv6 mapping _ for value 0x17
R/W
00
5 – 4
DSCP[45:44]
Ipv4 and Ipv6 mapping _ for value 0x16
R/W
00
3 – 2
DSCP[43:42]
Ipv4 and Ipv6 mapping _ for value 0x15
R/W
00
1 – 0
DSCP[41:40]
Ipv4 and Ipv6 mapping _ for value 0x14
R/W
00
Register 150 (0x96): TOS Priority Control Register 6
7 – 6
DSCP[55:54]
Ipv4 and Ipv6 mapping _ for value 0x1B
R/W
00
5 – 4
DSCP[53:52]
Ipv4 and Ipv6 mapping _ for value 0x1A
R/W
00
3 – 2
DSCP[51:50]
Ipv4 and Ipv6 mapping _ for value 0x19
R/W
00
1 – 0
DSCP[49:48]
Ipv4 and Ipv6 mapping _ for value 0x18
R/W
00
Register 151 (0x97): TOS Priority Control Register 7
7 – 6
DSCP[63:62]
Ipv4 and Ipv6 mapping _ for value 0x1F
R/W
00
5 – 4
DSCP[61:60]
Ipv4 and Ipv6 mapping _ for value 0x1E
R/W
00
3 – 2
DSCP[59:58]
Ipv4 and Ipv6 mapping _ for value 0x1D
R/W
00
1 – 0
DSCP[57:56]
Ipv4 and Ipv6 mapping _ for value 0x1C
R/W
00
Register 152 (0x98): TOS Priority Control Register 8
7 – 6
DSCP[71:70]
Ipv4 and Ipv6 mapping _ for value 0x23
R/W
00
5 – 4
DSCP[69:68]
Ipv4 and Ipv6 mapping _ for value 0x22
R/W
00
3 – 2
DSCP[67:66]
Ipv4 and Ipv6 mapping _ for value 0x21
R/W
00
1 – 0
DSCP[65:64]
Ipv4 and Ipv6 mapping _ for value 0x20
R/W
00
Register 153 (0x99): TOS Priority Control Register 9
7 – 6
DSCP[79:78]
Ipv4 and Ipv6 mapping _ for value 0x27
R/W
00
5 – 4
DSCP[77:76]
Ipv4 and Ipv6 mapping _ for value 0x26
R/W
00
3 – 2
DSCP[75:74]
Ipv4 and Ipv6 mapping _ for value 0x25
R/W
00
1 – 0
DSCP[73:72]
Ipv4 and Ipv6 mapping _ for value 0x24
R/W
00
Register 154 (0x9A): TOS Priority Control Register 10
7 – 6
DSCP[87:86]
Ipv4 and Ipv6 mapping _ for value 0x2B
R/W
00
5 – 4
DSCP[85:84]
Ipv4 and Ipv6 mapping _ for value 0x2A
R/W
00
3 – 2
DSCP[83:82]
Ipv4 and Ipv6 mapping _ for value 0x29
R/W
00
1 – 0
DSCP[81:80]
Ipv4 and Ipv6 mapping _ for value 0x28
R/W
00
Register 155 (0x9B): TOS Priority Control Register 11
7 – 6
DSCP[95:94]
Ipv4 and Ipv6 mapping _ for value 0x2F
R/W
00
5 – 4
DSCP[93:92]
Ipv4 and Ipv6 mapping _ for value 0x2E
R/W
00
3 – 2
DSCP[91:90]
Ipv4 and Ipv6 mapping _ for value 0x2D
R/W
00
1 – 0
DSCP[89:88]
Ipv4 and Ipv6 mapping _ for value 0x2C
R/W
00
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 156 (0x9C): TOS Priority Control Register 12
7 – 6
DSCP[103:102]
Ipv4 and Ipv6 mapping _ for value 0x33
R/W
00
5 – 4
DSCP[101:100]
Ipv4 and Ipv6 mapping _ for value 0x32
R/W
00
3 – 2
DSCP[99:98]
Ipv4 and Ipv6 mapping _ for value 0x31
R/W
00
1 – 0
DSCP[97:96]
Ipv4 and Ipv6 mapping _ for value 0x30
R/W
00
Register 157 (0x9D): TOS Priority Control Register 13
7 – 6
DSCP[111:110]
Ipv4 and Ipv6 mapping _ for value 0x37
R/W
00
5 – 4
DSCP[109:108]
Ipv4 and Ipv6 mapping _ for value 0x36
R/W
00
3 – 2
DSCP[107:106]
Ipv4 and Ipv6 mapping _ for value 0x35
R/W
00
1 – 0
DSCP[105:104]
Ipv4 and Ipv6 mapping _ for value 0x34
R/W
00
Register 158 (0x9E): TOS Priority Control Register 14
7 – 6
DSCP[119:118]
Ipv4 and Ipv6 mapping _ for value 0x3B
R/W
00
5 – 4
DSCP[117:116]
Ipv4 and Ipv6 mapping _ for value 0x3A
R/W
00
3 – 2
DSCP[115:114]
Ipv4 and Ipv6 mapping _ for value 0x39
R/W
00
1 – 0
DSCP[113:112]
Ipv4 and Ipv6 mapping _ for value 0x38
R/W
00
Register 159 (0x9F): TOS Priority Control Register 15
7 – 6
DSCP[127:126]
Ipv4 and Ipv6 mapping _ for value 0x3F
R/W
00
5 – 4
DSCP[125:124]
Ipv4 and Ipv6 mapping _ for value 0x3E
R/W
00
3 – 2
DSCP[123:122]
Ipv4 and Ipv6 mapping _ for value 0x3D
R/W
00
1 – 0
DSCP[121:120]
Ipv4 and Ipv6 mapping _ for value 0x3C
R/W
00
Register 165 (0xA5): Reserved
7 0
Reserved
N/A, do not change
RO
0x30
Register 176 (0xB0): Port 1 Control 8
Register 192 (0xC0): Port 2 Control 8
Register 208 (0xD0): Port 3 Control 8
Register 224 (0xE0): Port 4 Control 8
Register 240 (0xF0): Port 5 Control 8
7 – 4
Reserved
RO
0000
3
Insert Source Port PVID for
Untagged Packet Destination
to Highest Egress Port
Note: Enabled by the register
135 bit 2
Register 176: insert source Port 1 PVID for
untagged frame at egress Port 5
Register 192: insert source Port 2 PVID for
untagged frame at egress Port 5
Register 208: insert source Port 3 PVID for
untagged frame at egress Port 5
Register 224: insert source Port 4 PVID for
untagged frame at egress Port 5
Register 240: insert source Port 5 PVID for
untagged frame at egress Port 4
R/W
0
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
2
Insert Source Port PVID for
Untagged Packet Destination
to Second Highest Egress Port
Note: Enabled by the Register
135 bit 2
Register 176: insert source Port 1 PVID for
untagged frame at egress pPort 4
Register 192: insert source Port 2 PVID for
untagged frame at egress Port 4
Register 208: insert source Port 3 PVID for
untagged frame at egress Port 4
Register 224: insert source Port 4 PVID for
untagged frame at egress Port 3
Register 240: insert source Port 5 PVID for
untagged frame at egress Port 3
R/W
0
1
Insert Source Port PVID for
Untagged Packet Destination
to Second Lowest Egress Port
Note: Enabled by the Register
135 bit 2
Register 176: insert source Port 1 PVID for
untagged frame at egress Port 3
Register 192: insert source Port 2 PVID for
untagged frame at egress Port 3
Register 208: insert source Port 3 PVID for
untagged frame at egress Port 2
Register 224: insert source Port 4 PVID for
untagged frame at egress Port 2
Register 240: insert source Port 5 PVID for
untagged frame at egress Port 2
R/W
0
0
Insert Source Port PVID for
Untagged Packet Destination
to Lowest Egress Port
Note: Enabled by the Register
135 bit 2
Register 176: insert source Port 1 PVID for
untagged frame at egress Port 2
Register 192: insert source Port 2 PVID for
untagged frame at egress Port 1
Register 208: insert source Port 3 PVID for
untagged frame at egress Port 1
Register 224: insert source Port 4 PVID for
untagged frame at egress Port 1
Register 240: insert source Port 5 PVID for
untagged frame at egress Port 1
R/W
0
Register 177 (0xB1): Port 1 Control 9
Register 193 (0xC1): Port 2 Control 9
Register 209 (0xD1): Port 3 Control 9
Register 225 (0xE1): Port 4 Control 9
Register 241 (0xF1): Port 5 Control 9
7 – 2
Reserved
RO
0000000
1
4 Queue Split Enable
This bit in combination with Register16/32/48/64/80
bit 0 will select the split of ½/4 queues:
{Register177 bit 1, Register16 bit 0} = 11, reserved.
10, the port output queue is split into four priority
queues or if map 802.1p to priority 0-3 mode.
01, the port output queue is split into two priority
queues or if map 802.1p to priority 0-3 mode.
00, single output queue on the port. There is no
priority differentiation even though packets are
classified into high and low priority.
R/W
0
0
Enable Dropping Tag
0 = disable tag drop
1 = enable tag drop
R/W
0
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 178 (0xB2): Port 1 Control 10
Register 194 (0xC2): Port 2 Control 10
Register 210 (0xD2): Port 3 Control 10
Register 226 (0xE2): Port 4 Control 10
Register 242 (0xF2): Port 5 Control 10
7
Enable Port Transmit Queue 3
Ratio
0, strict priority, will transmit all the packets from
this priority queue 3 before transmit lower priority
queue.
1, bit [6:0] reflect the packet number allow to
transmit from this priority queue 3 within a certain
time.
R/W
1
6 – 0
Port Transmit Queue 3
Ratio[6:0]
Packet number for Transmit Queue 3 for highest
priority packets in four queues mode.
R/W
0001000
Register 179 (0xB3): Port 1 Control 11
Register 195 (0xC3): Port 2 Control 11
Register 211 (0xD3): Port 3 Control 11
Register 227 (0xE3): Port 4 Control 11
Register 243 (0xF3): Port 5 Control 11
7
Enable Port Transmit Queue 2
Ratio
0, strict priority, will transmit all the packets from
this priority queue 2 before transmit lower priority
queue.
1, bit [6:0] reflect the packet number allow to
transmit from this priority queue 1 within a certain
time.
R/W
1
6 – 0
Port Transmit Queue 2
Ratio[6:0]
Packet number for Transmit Queue 2 for high/low
priority packets in high/low priority packets in four
queues mode.
R/W
0000100
Register 180 (0xB4): Port 1 Control 12
Register 196 (0xC4): Port 2 Control 12
Register 212 (0xD4): Port 3 Control 12
Register 228 (0xE4): Port 4 Control 12
Register 244 (0xF4): Port 5 Control 12
7
Enable Port Transmit Queue 1
Rate
0, strict priority, will transmit all the packets from
this priority queue 1 before transmit lower priority
queue.
1, bit [6:0] reflect the packet number allow to
transmit from this priority queue 1 within a certain
time.
R/W
1
6 – 0
Port Transmit Queue 1
Ratio[6:0]
Packet number for Transmit Queue 1 for low/high
priority packets in four queues mode and high
priority packets in two queues mode.
R/W
0000010
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 181 (0xB5): Port 1 Control 13
Register 197 (0xC5): Port 2 Control 13
Register 213 (0xD5): Port 3 Control 13
Register 229 (0xE5): Port 4 Control 13
Register 245 (0xF5): Port 5 Control 13
7
Enable Port Transmit Queue 0
Rate
0, strict priority, will transmit all the packets from
this priority queue 0 before transmit lower priority
queue.
1, bit [6:0] reflect the packet number allow to
transmit from this priority queue 0 within a certain
time.
R/W
1
6 – 0
Port Transmit Queue 0
Ratio[6:0]
Packet number for Transmit Queue 0 for lowest
priority packets in four queues mode and low
priority packets in two queues mode.
R/W
0000001
Register 182 (0xB6): Port 1 Rate Limit Control
Register 198 (0xC6): Port 2 Rate Limit Control
Register 214 (0xD6): Port 3 Rate Limit Control
Register 230 (0xE6): Port 4 Rate Limit Control
Register 246 (0xF6): Port 5 Rate Limit Control
7 – 5
Reserved
RO
000
4
Ingress Rate Limit Flow
Control Enable
1 = Flow Control is asserted if the port’s receive
rate is exceeded.
0 = Flow Control is not asserted if the port’s receive
rate is exceeded.
R/W
0
3 – 2
Limit Mode
Ingress Limit Mode
These bits determine what kinds of frames are
limited and counted against ingress rate limiting.
= 00, limit and count all frames.
= 01, limit and count Broadcast, Multicast, and
flooded unicast frames.
= 10, limit and count Broadcast and Multicast
frames only.
= 11, limit and count Broadcast frames only.
R/W
00
1
Count IFG
Count IFG bytes
= 1, each frame’s minimum inter frame gap.
(IFG) bytes (12 per frame) are included in Ingress
and Egress rate limiting calculations.
= 0, IFG bytes are not counted.
R/W
0
0
Count Pre
Count Preamble bytes
= 1, each frame’s preamble bytes (8 per frame) are
included in Ingress and Egress rate limiting
calculations.
= 0, preamble bytes are not counted.
R/W
0
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Revision-1.1
Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 183 (0xB7): Port 1 Priority 0 Ingress Limit Control 1
Register 199 (0xC7): Port 2 Priority 0 Ingress Limit Control 1
Register 215 (0xD7): Port 3 Priority 0 Ingress Limit Control 1
Register 231 (0xE7): Port 4 Priority 0 Ingress Limit Control 1
Register 247 (0xF7): Port 5 Priority 0 Ingress Limit Control 1
7
Reserved
RO
0
6 – 0
Port Based Priority 0 Ingress
Limit
Ingress data rate limit for priority 0 frames
Ingress traffic from this port is shaped according to
the Data Rate Selected Table. See the table follow
the end of Egress limit control registers.
R/W
0000000
Register 184 (0xB8): Port 1 Priority 1 Ingress Limit Control 2
Register 200 (0xC8): Port 2 Priority 1 Ingress Limit Control 2
Register 216 (0xD8): Port 3 Priority 1 Ingress Limit Control 2
Register 232 (0xE8): Port 4 Priority 1 Ingress Limit Control 2
Register 248 (0xF8): Port 5 Priority 1 Ingress Limit Control 2
7
Reserved
RO
0
6 – 0
Port Based Priority 1 Ingress
Limit
Ingress data rate limit for priority 1 frames
Ingress traffic from this port is shaped according to
the Data Rate Selected Table. See the table follow
the end of Egress limit control registers.
R/W
0000000
Register 185 (0xB9): Port 1 Priority 2 Ingress Limit Control 3
Register 201 (0xC9): Port 2 Priority 2 Ingress Limit Control 3
Register 217 (0xD9): Port 3 Priority 2 Ingress Limit Control 3
Register 233 (0xE9): Port 4 Priority 2 Ingress Limit Control 3
Register 249 (0xF9): Port 5 Priority 2 Ingress Limit Control 3
7
Reserved
RO
0
6 – 0
Port Based Priority 2 Ingress
Limit
Ingress data rate limit for priority 2 frames
Ingress traffic from this port is shaped according to
the Data Rate Selected Table. See the table follow
the end of Egress limit control registers.
R/W
0000000
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 186 (0xBA): Port 1 Priority 3 Ingress Limit Control 4
Register 202 (0xCA): Port 2 Priority 3 Ingress Limit Control 4
Register 218 (0xDA): Port 3 Priority 3 Ingress Limit Control 4
Register 234 (0xEA): Port 4 Priority 3 Ingress Limit Control 4
Register 250 (0xFA): Port 5 Priority 3 Ingress Limit Control 4
7
Reserved
RO
0
6 – 0
Port Based Priority 3 Ingress
Limit
Ingress data rate limit for priority 3 frames
Ingress traffic from this port is shaped according to
the Data Rate Selected Table. See the table follow
the end of Egress limit control registers.
R/W
0000000
Register 187 (0xBB): Port 1 Queue 0 Egress Limit Control 1
Register 203 (0xCB): Port 2 Queue 0 Egress Limit Control 1
Register 219 (0xDB): Port 3 Queue 0 Egress Limit Control 1
Register 235 (0xEB): Port 4 Queue 0 Egress Limit Control 1
Register 251 (0xFB): Port 5 Queue 0 Egress Limit Control 1
7
Reserved
RO
0
6 – 0
Port Queue 0 Egress Limit
Egress data rate limit for priority 0 frames
Egress traffic from this priority queue is shaped
according to the Data Rate Selected Table. See the
table follow the end of Egress limit control registers.
In four queues mode, it is lowest priority.
In two queues mode, it is low priority.
R/W
0000000
Register 188 (0xBC) : Port 1 Queue 1 Egress Limit Control 2
Register 204 (0xCC) : Port 2 Queue 1 Egress Limit Control 2
Register 220 (0xDC) : Port 3 Queue 1 Egress Limit Control 2
Register 236 (0xEC) : Port 4 Queue 1 Egress Limit Control 2
Register 252 (0xFC) : Port 5 Queue 1 Egress Limit Control 2
7
Reserved
RO
0
6 – 0
Port Queue 1 Egress Limit
Egress data rate limit for priority 1 frames
Egress traffic from this priority queue is shaped
according to the Data Rate Selected Table. See the
table follow the end of Egress limit control registers.
In four queues mode, it is low/high priority.
In two queues mode, it is high priority.
R/W
0000000
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Advanced Control Registers (Continued)
Address
Name
Description
Mode
Default
Register 189 (0xBD): Port 1 Queue 2 Egress Limit Control 3
Register 205 (0xCD): Port 2 Queue 2 Egress Limit Control 3
Register 221 (0xDD): Port 3 Queue 2 Egress Limit Control 3
Register 237 (0xED): Port 4 Queue 2 Egress Limit Control 3
Register 253 (0xFD): Port 5 Queue 2 Egress Limit Control 3
7
Reserved
RO
0
6 – 0
Port Queue 2 Egress Limit
Egress data rate limit for priority 2 frames
Egress traffic from this priority queue is shaped
according to the Data Rate Selected Table. See the
table follow the end of Egress limit control registers.
In four queues mode, it is high/low priority.
R/W
0000000
Register 190 (0xBE) : Port 1 Queue 3 Egress Limit Control 4
Register 206 (0xCE) : Port 2 Queue 3 Egress Limit Control 4
Register 222 (0xDE) : Port 3 Queue 3 Egress Limit Control 4
Register 238 (0xEE): Port 4 Queue 3 Egress Limit Control 4
Register 254 (0xFE): Port 5 Queue 3 Egress Limit Control 4
7
Reserved
RO
0
6 – 0
Port Queue 3 Egress Limit
Egress data rate limit for priority 3 frames
Egress traffic from this priority queue is shaped
according to the Data Rate Selected Table. See the
table follow the end of Egress limit control registers.
In four queues mode, it is highest priority.
R/W
0000000
Note:
1. In the port priority 0-3 ingress rate limit mode, will need to set all related ingress/egress ports to two queues or four queues mode.
2. In the port queue 0-3 egress rate limit mode, the highest priority get exact rate limit based on the rate select table, other priorities packets rate
are based upon the ratio of the Register Port Control 10/11/12/13 when use more than one egress queue per port.
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Revision-1.1
Data Rate Limit Selection Limit Table
Table 14. 10/100BT Rate Selection for the Rate limit
Data Rate Limit for
Ingress or egress
100BT
Priority/Queue 0-3 Ingress/egress limit Control
Register bit [6:0] = decimal
10BT
Priority/Queue 0-3 Ingress/egress limit
Control Register bit [6:0] = decimal
1 Mbps <= rate <= 99 Mbps
rate(decimal integer 1-99)
1 Mbps <= rate <= 9 Mbps
rate(decimal integer 1-9)
0 or 100 (decimal), ‘0’ is default value
0 or 10 (decimal), ‘0’ is default value
Less than 1Mbps see as below
Decimal
64 Kbps
7’d101
128 Kbps
7’d102
192 Kbps
7’d103
256 Kbps
7’d104
320 Kbps
7’d105
384 Kbps
7’d106
448 Kbps
7’d107
512 Kbps
7’d108
576 Kbps
7’d109
640 Kbps
7’d110
704 Kbps
7’d111
768 Kbps
7’d112
832 Kbps
7’d113
896 Kbps
7’d114
960 Kbps
7’d115
Address
Name
Description
Mode
Default
Register 191(0xBF): Testing Register 1
7 - 0
Reserved
N/A, do not change.
RO
0x80
Register 207(0xCF): Reserved Control Register
7 - 0
Reserved
N/A, do not change.
RO
0x15
Register 223(0xDF): Testing Register 2
7 - 0
Reserved
R/W
0x0C
Register 239(0xEF): Port 3 Copper or Fiber Control
7
Fiber select for Port 3
0 = Port 3 is copper port (default)
1 = Port 3 is fiber port.
R/W
0
6 - 0
Reserved
N/A, Do not change.
RO
0110010
Register 255(0xFF): Testing Register 3
7- 0
Reserved
N/A, Do not change.
RO
0x00
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Revision-1.1
Static MAC Address Table
KSZ8895MQX/RQX/FQX/ML has a static and a dynamic address table. When a DA look-up is requested, both tables
will be searched to make a packet forwarding decision. When an SA look-up is requested, only the dynamic table is
searched for aging, migration, and learning purposes. The static DA look-up result will have precedence over the
dynamic DA look-up result. If there are DA matches in both tables, the result from the static table will be used. The
static table can only be accessed and controlled by an external SPI master (usually a processor). The entries in the
static table will not be aged out by KSZ8895MQX/RQX/FQX/ML. An external device does all addition, modification
and deletion.
Note:
Register bit assignments are different for static MAC table reads and static MAC table write, as shown in Table 15.
Table 15. Static MAC Address Table
Address
Name
Description
Mode
Default
Format of Static MAC Table for Reads (32 entries)
63-57
FID
Filter VLAN ID, representing one of the 128 active
VLANs.
RO
0000000
56
Use FID
1, use (FID+MAC) to look-up in static table.
0, use MAC only to look-up in static table.
RO
0
55
Reserved
Reserved.
RO
N/A
54
Override
1, override spanning tree “transmit enable = 0” or
“receive enable = 0* setting. This bit is used for
spanning tree implementation.
0, no override.
RO
0
53
Valid
1, this entry is valid, the look-up result will be used.
0, this entry is not valid.
RO
0
52-48
Forwarding Ports
The 5 bits control the forward ports, example:
00001, forward to Port 1
00010, forward to Port 2
…..
10000, forward to Port 5
00110, forward to Port 2 and Port 3
11111, broadcasting (excluding the ingress port)
RO
00000
47-0
MAC Address (DA)
48 bit MAC address.
RO
0x0
Format of Static MAC Table for Writes (32 entries)
62-56
FID
Filter VLAN ID, representing one of the 128 active
VLANs.
W
0000000
55
Use FID
1, use (FID+MAC) to look-up in static table.
0, use MAC only to look-up in static table.
W
0
54
Override
1, override spanning tree “transmit enable = 0” or
“receive enable = 0” setting. This bit is used for
spanning tree implementation.
0, no override.
W
0
53
Valid
1, this entry is valid, the look-up result will be used.
0, this entry is not valid.
W
0
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Address
Name
Description
Mode
Default
52-48
Forwarding Ports
The 5 bits control the forward ports, example:
00001, forward toPort 1
00010, forward to Port 2
.....
10000, forward to Port 5
00110, forward to Port 2 and Port 3
11111, broadcasting (excluding the ingress port)
W
00000
47-0
MAC Address (DA)
48-bit MAC address.
W
0x0
Examples:
(1) Static Address Table Read (read the 2nd entry)
Write to Register 110 with 0x10 (read static table selected)
Write to Register 111 with 0x1 (trigger the read operation)
Then
Read Register 113 (63-56)
Read Register 114 (55-48)
Read Register 115 (47-40)
Read Register 116 (39-32)
Read Register 117 (31-24)
Read Register 118 (23-16)
Read Register 119 (15-8)
Read Register 120 (7-0)
(2) Static Address Table Write (write the 8th entry)
Write to Register 110 with 0x10 (read static table selected)
Write Register 113 (62-56)
Write Register 114 (55-48)
Write Register 115 (47-40)
Write Register 116 (39-32)
Write Register 117 (31-24)
Write Register 118 (23-16)
Write Register 119 (15-8)
Write Register 120 (7-0)
Write to Register 110 with 0x00 (write static table selected)
Write to Register 111 with 0x7 (trigger the write operation)
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Revision-1.1
VLAN Table
The VLAN table is used for VLAN table look-up. If 802.1q VLAN mode is enabled (Register 5 bit 7 = 1), this table is
used to retrieve VLAN information that is associated with the ingress packet. There are three fields for FID (filter ID),
Valid, and VLAN membership in the VLAN table. The three fields must be initialized before the table is used. There is
no VID field because 4096 VIDs are used as a dedicated memory address index into a 1024x52-bit memory space.
Each entry has four VLANs. Each VLAN has 13 bits. Four VLANs need 52 bits. There are a total of 1024 entries to
support a total of 4096 VLAN IDs by using dedicated memory address and data bits. Refer to Table 16 for details.
FID has 7-bits to support 128 active VLANs.
Table 16. VLAN Table
Address
Name
Description
Mode
Initial Value
suggestion
12
Valid
1, the entry is valid.
0, entry is invalid.
R/W
0
11 7
Membership
Specify which ports are members of the VLAN.
If a DA look-up fails (no match in both static and
dynamic tables), the packet associated with this VLAN
will be forwarded to ports specified in this field.
E.g., 11001 means port 5, port 4 and port 1.
R/W
11111
6 0
FID
Filter ID. KSZ8895MLU supports 128 active VLANs
represented by these seven bit fields. FID is the
mapped ID. If 802.1q VLAN is enabled, the look-up in
MAC table will be based on FID+DA and FID+SA.
R/W
0
If 802.1q VLAN mode is enabled, KSZ8895MLU assigns a VID to every ingress packet when the packet is untagged
or tagged with a null VID, the packet is assigned with the default port VID of the ingress port. If the packet is tagged
with non-null VID, the VID in the tag is used. The look-up process starts from the VLAN table look-up based on VID
number with its dedicated memory address and data bits. If the entry is not valid in the VLAN table, the packet is
dropped and no address learning occurs. If the entry is valid, the FID is retrieved. The FID+DA and FID+SA lookups
in MAC tables are performed. The FID+DA look-up determines the forwarding ports. If FID+DA fails for look-up in the
MAC table, the packet is broadcast to all the members or specified members (excluding the ingress port) based on
the VLAN table. If FID+SA fails, the FID+SA is learned. To communicate between different active VLANs, set the
same FID; otherwise set a different FID.
The VLAN table configuration is organized as 1024 VLAN sets, each VLAN set consists of four VLAN entries, to
support up to 4096 VLAN entries. Each VLAN set has 52 bits and should be read or written at the same time
specified by the indirect address.
The VLAN entries in the VLAN set is mapped to indirect data registers as follow:
Entry0[12:0] maps to the VLAN set bits[12 0] {register119[4:0], register120[7:0]}
Entry1[12:0] maps to the VLAN set bits[25 13]{register117[1:0], register118[7:0], register119[7:5]}
Entry2[12:0] maps to the VLAN set bits[38 26]{register116[6:0], register117[7:2]}
Entry3[12:0] maps to the VLAN set bits[51 39]{register114[3:0], register115[7:0], register116[7]}
In order to read one VLAN entry, the VLAN set is read first and the specific VLAN entry information can be extracted.
To update any VLAN entry, the VLAN set is read first then only the desired VLAN entry is updated and the whole
VLAN set is written back. Due to FID in VLAN table is 7-bit, so the VLAN table supports unique 128 flow VLAN
groups. Each VLAN set address is 10 bits long (Maximum is 1024) in the indirect address register 110 and 111, the
bit [9 8] of VLAN set address is at bit [1 0] of register 110, and the bit [7 0] of VLAN set address is at bit [7-0] of
register 111. Each Write and Read can access to four consecutive VLAN entries.
Examples:
(1) VLAN Table Read (read the VID=2 entry)
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Write the indirect control and address registers first
Write to Register 110 (0x6E) with 0x14 (read VLAN table selected)
Write to Register 111 (0x6F) with 0x0 (trigger the read operation for VID=0, 1, 2, 3 entries)
Then read the indirect data registers bits [38-26] for VID=2 entry
Read Register 116 (0x74), (register 116 [6:0] are bits 12 6 of VLAN VID=2 entry)
Read Register 117 (0x75), (register 117 [7:2] are bits 5 0 of VLAN VID=2 entry)
(2) VLAN Table Write (write the VID=10 entry)
Read the VLAN set that contains VID=8, 9, 10, 11.
Write to Register 110 (0x6E) with 0x14 (read VLAN table selected)
Write to Register 111 (0x6F) with 0x02 (trigger the read operation and VID=8, 9, 10, 11 indirect
address)
Read the VLAN set first by the indirect data registers 114, 115, 116, 117, 118, 119, 120.
Modify the indirect data registers bits [38 26] by the register 116 bit [6-0] and register 117 bit [7 2] as
follows:
Write to Register 116 (0x74), (register116 [6:0] are bits 12 6 of VLAN VID=10 entry)
Write to Register 117 (0x75), (register117 [7:2] are bits 5 0 of VLAN VID=10 entry)
Then write the indirect control and address registers
Write to Register 110 (0x6E) with 0x04 (write VLAN table selected)
Write to Register 111 (0x6F) with 0x02 (trigger the write operation and VID=8, 9, 10, 11 indirect
address)
Error! Reference source not found. shows the relationship of the indirect address/data registers and VLAN ID.
Table 17. VLAN ID and Indirect Registers
Indirect Address
High/Low Bit[9-0]
for VLAN Sets
Indirect Data
Registers Bits for
Each VLAN Entry
VID
Numbers
VID bit[12-2] in VLAN
Tag
VID bit[1-0] in VLAN Tag
0
Bits[12 0]
0
0
0
0
Bits[25 13]
1
0
1
0
Bits[38 26]
2
0
2
0
Bits[51 39]
3
0
3
1
Bits[12 0]
4
1
0
1
Bits[25 13]
5
1
1
1
Bits[38 26]
6
1
2
1
Bits[51 39]
7
1
3
2
Bits[12 0]
8
2
0
2
Bits[25 13]
9
2
1
2
Bits[38 26]
10
2
2
2
Bits[51 39]
11
2
3
:
:
:
:
:
:
:
:
:
:
:
:
:
:
:
1023
Bits[12 0]
4092
1023
0
1023
Bits[25 13]
4093
1023
1
1023
Bits[38 26]
4094
1023
2
1023
Bits[51 39]
4095
1023
3
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Dynamic MAC Address Table
This table is read only. The contents are maintained by the KSZ8895MQX/RQX/FQX/ML only.
Table 18. Dynamic MAC Address Table
Address
Name
Description
Mode
Default
Format of Dynamic MAC Address Table (1K entries)
71
MAC Empty
1, there is no valid entry in the table.
0, there are valid entries in the table.
RO
1
70-61
No of Valid Entries
Indicates how many valid entries in the table.
0x3ff means 1K entries
0x1 and bit 71 = 0: means 2 entries
0x0 and bit 71 = 0: means 1 entry
0x0 and bit 71 = 1: means 0 entry
RO
0
60-59
Time Stamp
2-bit counters for internal aging
RO
58-56
Source Port
The source port where FID+MAC is learned.
000 Port 1
001 Port 2
010 Port 3
011 Port 4
100 Port 5
RO
0x0
55
Data Ready
1, The entry is not ready, retry until this bit is set to 0.
0, The entry is ready.
RO
54-48
FID
Filter ID.
RO
0x0
47-0
MAC Address
48-bit MAC address.
RO
0x0
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Examples:
(1) Dynamic MAC Address Table Read (read the 1st entry), and retrieve the MAC table size
Write to Register 110 with 0x18 (read dynamic table selected)
Write to Register 111 with 0x0 (trigger the read operation) and then
Read Register 112 (71-64)
Read Register 113 (63-56); // the above two registers show # of entries
Read Register 114 (55-48) // if bit 55 is 1, restart (reread) from this register
Read Register 115 (47-40)
Read Register 116 (39-32)
Read Register 117 (31-24)
Read Register 118 (23-16)
Read Register 119 (15-8)
Read Register 120 (7-0)
(2) Dynamic MAC Address Table Read (read the 257th entry), without retrieving # of entries information
Write to Register 110 with 0x19 (read dynamic table selected)
Write to Register 111 with 0x1 (trigger the read operation) and then
Read Register 112 (71-64)
Read Register 113 (63-56)
Read Register 114 (55-48) // if bit 55 is 1, restart (reread) from this register
Read Register 115 (47-40)
Read Register 116 (39-32)
Read Register 117 (31-24)
Read Register 118 (23-16)
Read Register 119 (15-8)
Read Register 120 (7-0)
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MIB (Management Information Base) Counters
The MIB counters are provided on per port basis. These counters are read using indirect memory access as below:
For Port 1
Table 19. Port1 MIB Counter Indirect Memory Offerts
Offset
Counter Name
Description
0x0
RxLoPriorityByte
Rx lo-priority (default) octet count including bad packets.
0x1
RxHiPriorityByte
Rx hi-priority octet count including bad packets.
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 or 1522 bytes).
0x5
RxJabbers
Rx packets longer than 1522B w/either CRC errors, alignment errors, or symbol errors
(depends on max packet size setting) or Rx packets longer than 1916B only.
0x6
RxSymbolError
Rx packets w/ invalid data symbol and legal preamble, packet size.
0x7
RxCRCerror
Rx packets within (64,1522) bytes w/an integral number of bytes and a bad CRC (upper limit
depends on max packet size setting).
0x8
RxAlignmentError
Rx packets within (64,1522) bytes w/a non-integral number of bytes and a bad CRC (upper
limit depends on max packet size setting).
0x9
RxControl8808Pkts
The number of MAC control frames received by a port with 88-08h in EtherType field.
0xA
RxPausePkts
The 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 errored broadcast packets or valid multicast
packets).
0xC
RxMulticast
Rx good multicast packets (not including MAC control frames, errored 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
Rx1024to1522Octets
Total Rx packets (bad packets included) that are between 1024 and 1522 octets in length
(upper limit depends on max packet size setting).
0x14
TxLoPriorityByte
Tx lo-priority good octet count, including PAUSE packets.
0x15
TxHiPriorityByte
Tx hi-priority 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
The number of PAUSE frames transmitted by a port.
0x18
TxBroadcastPkts
Tx good broadcast packets (not including errored broadcast or valid multicast packets).
0x19
TxMulticastPkts
Tx good multicast packets (not including errored 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.
For port 2, the base is 0x20, same offset definition (0x20-0x3f)
For port 3, the base is 0x40, same offset definition (0x40-0x5f)
For port 4, the base is 0x60, same offset definition (0x60-0x7f)
For port 5, the base is 0x80, same offset definition (0x80-0x9f)
Table 20. Format of “Per Port” MIB Counter
Address
Name
Description
Mode
Default
Format of Per Port MIB Counters (16 entries)
31
Overflow
1, Counter overflow.
0, No Counter overflow.
RO
0
30
Count Valid
1, Counter value is valid.
0, Counter value is not valid.
RO
0
29-0
Counter Values
Counter value.
RO
0
Table 21. All Port Dropped Packet MIB Counters
Offset
Counter Name
Description
0x100
Port1 Tx Drop Packets
Tx packets dropped due to lack of resources.
0x101
Port2 Tx Drop Packets
Tx packets dropped due to lack of resources.
0x102
Port3 Tx Drop Packets
Tx packets dropped due to lack of resources.
0x103
Port4 Tx Drop Packets
Tx packets dropped due to lack of resources.
0x104
Port5 Tx Drop Packets
Tx packets dropped due to lack of resources.
0x105
Port1 Rx Drop Packets
Rx packets dropped due to lack of resources.
0x106
Port2 Rx Drop Packets
Rx packets dropped due to lack of resources.
0x107
Port3 Rx Drop Packets
Rx packets dropped due to lack of resources.
0x108
Port4 Rx Drop Packets
Rx packets dropped due to lack of resources.
0x109
Port5 Rx Drop Packets
Rx packets dropped due to lack of resources.
Table 22. Format of “All Dropped Packet” MIB Counter
Address
Name
Description
Mode
Default
Format of All Port Dropped Packet MIB Counters
30-16
Reserved
Reserved.
N/A
N/A
15-0
Counter Values
Counter value.
RO
0
Note:
All port dropped packet MIB counters do not indicate overflow or validity; therefore the application must keep track of overflow and valid
conditions.
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The KSZ8895MQX/RQX/FQX/ML provides a total of 34 MIB counters per port. These counters are used to monitor
the port detail activity for network management and maintenance. These MIB counters are read using indirect
memory access, per the following examples.
Programming Examples:
(1) MIB counter read (read port 1 Rx64Octets counter)
Write to Register 110 with 0x1c (read MIB counters selected)
Write to Register 111 with 0xe (trigger the read operation)
Then
Read Register 117 (counter value 31-24)
// If bit 31 = 1, there was a counter overflow
// If bit 30 = 0, restart (reread) from this register
Read Register 118 (counter value 23-16)
Read Register 119 (counter value 15-8)
Read Register 120 (counter value 7-0)
(2) MIB counter read (read port 2 Rx64Octets counter)
Write to Register 110 with 0x1c (read MIB counter selected)
Write to Register 111 with 0x2e (trigger the read operation)
Then
Read Register 117 (counter value 31-24)
//If bit 31 = 1, there was a counter overflow
//If bit 30 = 0, restart (reread) from this register
Read Register 118 (counter value 23-16)
Read Register 119 (counter value 15-8)
Read Register 120 (counter value 7-0)
(3) MIB counter read (read port 1 tx drop packets)
Write to Register 110 with 0x1d
Write to Register 111 with 0x00
Then
Read Register 119 (counter value 15-8)
Read Register 120 (counter value 7-0)
Note:
To read out all the counters, the best performance over the SPI bus is (160+3) × 8 × 80 = 104us, where there are 255 registers, 3 overhead, 8
clocks per access, at 12.5MHz. In the heaviest condition, the byte counter will overflow in 2 minutes. It is recommended that the software read all
the counters at least every 30 seconds. The per port MIB counters are designed as “read clear.” A per port MIB counter will be cleared after it is
accessed. All port dropped packet MIB counters are not cleared after they are accessed. The application needs to keep track of overflow and valid
conditions on these counters.
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MIIM Registers
All the registers defined in this section can be also accessed via the SPI interface. Note: different mapping
mechanisms are used for MIIM and SPI. The “PHYAD” defined in IEEE is assigned as “0x1” for Port 1, “0x2” for Port
2, “0x3” for Port 3, “0x4” for Port 4, and “0x5” for Port 5. The “REGAD” supported are 0x0-0x5 (0h-5h), 0x1D (1dh)
and 0x1F (1fh).
Address
Name
Description
Mode
Default
Register 0h: MII Control
15
Soft Reset
1, PHY soft reset.
0, Normal operation.
R/W
(SC)
0
14
Loop Back
1 = Perform MAC loopback, loop back path as follows:
Assume the loop-back is at Port 1 MAC, Port 2 is the
monitor port.
Port 1 MAC Loopback (Port 1 reg. 0, bit 14 = ‘1’)
Start: RXP2/RXM2 (Port 2). Can also start from
port 3, 4, 5
Loopback: MAC/PHY interface of Port 1’s MAC
End: TXP2/TXM2 (Port 2). Can also end at
Ports 3, 4, 5 respectively
Setting address ox3,4,5 reg. 0, bit 14 = ‘1’ will
perform MAC loopback on Ports 3, 4, 5 respectively.
0 = Normal Operation.
R/W
0
13
Force 100
1, 100Mbps.
0, 10Mbps.
R/W
1
12
AN Enable
1, Auto-negotiation enabled.
0, Auto-negotiation disabled.
R/W
1
11
Power Down
1, Power down.
0, Normal operation.
R/W
0
10
PHY Isolate
1, Electrical PHY isolation of PHY from Tx+/Tx-.
0, Normal operation.
R/W
0
9
Restart AN
1, Restart Auto-negotiation.
0, Normal operation.
R/W
0
8
Force Full Duplex
1, Full duplex.
0, Half duplex.
R/W
0
7
Collision Test
Not supported.
RO
0
6
Reserved
RO
0
5
Hp_mdix
1 = HP Auto MDI/MDI-X mode.
0 = Micrel Auto MDI/MDI-X mode.
R/W
1
4
Force MDI
1, Force MDI.
0, Normal operation. (MDIX transmit on TXP/TXM pair)
R/W
0
3
Disable Auto MDI/MDI-X
1, Disable auto MDI/MDI-X.
0, Enable auto MDI/MDI-X.
R/W
0
2
Disable far End fault
1, Disable far end fault detection.
0, Normal operation.
R/W
0
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MIIM Registers (Continued)
Address
Name
Description
Mode
Default
1
Disable Transmit
1, Disable transmit.
0, Normal operation.
R/W
0
0
Disable LED
1, Disable LED.
0, Normal operation.
R/W
0
Register 1h: MII Status
15
T4 Capable
0, Not 100 BASET4 capable.
RO
0
14
100 Full Capable
1, 100BASE-TX full-duplex capable.
0, Not capable of 100BASE-TX full-duplex.
RO
1
13
100 Half Capable
1, 100BASE-TX half-duplex capable.
0, Not 100BASE-TX half-duplex capable.
RO
1
12
10 Full Capable
1, 10BASE-T full-duplex capable.
0, Not 10BASE-T full-duplex capable.
RO
1
11
10 Half Capable
1, 10BASE-T half-duplex capable.
0, 10BASE-T half-duplex capable.
RO
1
10-7
Reserved
RO
0
6
Preamble Suppressed
Not supported.
RO
0
5
AN Complete
1, Auto-negotiation complete.
0, Auto-negotiation not completed.
RO
0
4
far End fault
1, far end fault detected.
0, No far end fault detected.
RO
0
3
AN Capable
1, Auto-negotiation capable.
0, Not auto-negotiation capable.
RO
1
2
Link Status
1, Link is up.
0, Link is down.
RO
0
1
Jabber Test
Not supported.
RO
0
0
Extended Capable
0, Not extended register capable.
RO
0
Register 2h: PHYID HIGH
15-0
Phyid High
High order PHYID bits.
RO
0x0022
Register 3h: PHYID LOW
15-0
Phyid Low
Low order PHYID bits.
RO
0x1450
Register 4h: Advertisement Ability
15
Next Page
Not supported.
RO
0
14
Reserved
RO
0
13
Remote fault
Not supported.
RO
0
12-11
Reserved
RO
0
10
Pause
1, Advertise pause ability.
0, Do not advertise pause ability.
R/W
1
9
Reserved
R/W
0
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MIIM Registers (Continued)
Address
Name
Description
Mode
Default
8
Adv 100 Full
1, Advertise 100 full-duplex ability.
0, Do not advertise 100 full-duplex ability.
R/W
1
7
Adv 100 Half
1, Advertise 100 half-duplex ability.
0, Do not advertise 100 half-duplex ability.
R/W
1
6
Adv 10 Full
1, Advertise 10 full-duplex ability.
0, Do not advertise 10 full-duplex ability.
R/W
1
5
Adv 10 Half
1, Advertise 10 half-duplex ability.
0, Do not advertise 10 half-duplex ability.
R/W
1
4-0
Selector Field
802.3
RO
00001
Register 5h: Link Partner Ability
15
Next Page
Not supported.
RO
0
14
LP ACK
Not supported.
RO
0
13
Remote fault
Not supported.
RO
0
12-11
Reserved
RO
0
10
Pause
1, link partner flow control capable.
0, link partner not flow control capable.
RO
0
9
Reserved
RO
0
8
Adv 100 Full
1, link partner 100BT full-duplex capable.
0, link partner not 100BT full-duplex capable.
RO
0
7
Adv 100 Half
1, link partner 100BT half-duplex capable.
0, link partner not 100BT half-duplex capable.
RO
0
6
Adv 10 Full
1, link partner 10BT full-duplex capable.
0, link partner not 10BT full-duplex capable.
RO
0
5
Adv 10 Half
1, link partner 10BT half-duplex capable.
0, link partner not 10BT half-duplex capable.
RO
0
4-0
Reserved
RO
00001
Register 1dh: LinkMD Control/Status
15
Vct_enable
1 = Enable cable diagnostic. AfterVCT test has
completed, this bit will be self-cleared.
0 = Indicate cable diagnostic test (if enabled) has
completed and the status information is valid for read.
R/W
(SC)
0
14-13
Vct_result
00 = Normal condition
01 = Open condition detected in cable
10 = Short condition detected in cable
11 = Cable diagnostic test has failed
RO
00
12
Vct 10M Short
1 = Less than 10 meter short
RO
0
11-9
Reserved
RO
0
8-0
Vct_fault_count
Distance to the fault.
It’s approximately 0.4m*vct_fault_count[8:0]
RO
000000000
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MIIM Registers (Continued)
Address
Name
Description
Mode
Default
Register 1fh: PHY Special Control/Status
15-11
Reserved
RO
00000
10-8
Port Operation Mode
Indication
Indicate the current state of port operation mode:
[000] = reserved
[001] = still in auto-negotiation
[010] = 10BASE-T half duplex
[011] = 100BASE-TX half duplex
[100] = reserved
[101] = 10BASE-T full duplex
[110] = 100BASE-TX full duplex
[111] = PHY/MII isolate
RO
000
7-6
Reserved
N/A, don’t change
RO
00
5
Polrvs
1 = Polarity is reversed
0 = Polarity is not reversed
RO
0
4
MDI-X status
1 = MDI
0 = MDI-X
RO
0
3
Force_lnk
1 = Force link pass
0 = Normal operation
R/W
0
2
Pwrsave
1 = Enable power save
0 = Disable power save
R/W
0
1
Remote Loopback
1 = Perform Remote loopback, loop back path as
follows:
Port 1 (PHY ID address 0x1 reg. 1f, bit 1 = ‘1’)
Start: RXP1/RXM1 (port 1)
Loopback: PMD/PMA of port 1’s PHY
End: TXP1/TXM1 (port 1)
Setting PHY ID address 0x2,3,4,5 reg. 1f, bit 1 = ‘1’
will perform remote loopback on port 2, 3, 4, 5.
0 = Normal Operation.
R/W
0
0
Reserved
RO
0
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Absolute Maximum Ratings(1)
Supply Voltage
(VDDAR, VDDAP, VDDC) ............................... –0.5V to +2.4V
(VDDAT, VDDIO) ......................................... –0.5V to +4.0V
Input Voltage ................................................ –0.5V to +4.0V
Output Voltage ............................................. –0.5V to +4.0V
Lead Temperature (soldering, 10 sec.) ...................... 260°C
Storage Temperature (TS) ......................... –55°C to +150°C
HBM ESD Rating ........................................................... 5KV
Operating Ratings(2)
Supply Voltage
(VDDAR, VDDC) ....................................... 1.140V to 1.260V
(VDDAT) ................................................ 3.135V to 3.465V
(VDDIO @ 3.3V) .................................... 3.135V to 3.465V
(VDDIO @ 2.5V) ..................................... 2.375V to 2.625V
(VDDIO @ 1.8V) ..................................... 1.710V to 1.890V
Ambient Temperature (TA)
Commercial ............................................ –0°C to +70°C
Industrial ............................................... –40°C to +85°C
Max Junction Temperature (TJ) ................................. 125°C
128-Pin Package Thermal Resistance(3)
PQFP Thermal Resistance (θJA) .................. 41.54°C/W
PQFP Thermal Resistance (θJC) .................. 19.78°C/W
LQFP Thermal Resistance (θJA) ................... 48.22°C/W
LQFP Thermal Resistance (θJC) .................. 13.95°C/W
Electrical Characteristics(4,5)
VIN = 1.2V/3.3V (typ.); TA = 25°C
Symbol
Parameter
Condition
Min.
Typ.
Max.
Units
100BASE-TX Operation—All Ports 100% Utilization
IDX
100BASE-TX (Transmitter) 3.3V Analog
VDDAT
86
mA
IDda
100BASE-TX 1.2V Analog
VDDAR
22
mA
IDDc
100BASE-TX 1.2V Digital
VDDC
42
mA
IDDIO
100BASE-TX (Digital IO) Standalone 5-port
VDDIO
2.4
mA
IDDIO
3.3V Digital IO SW5-MII MAC/PHY + P5-MII
VDDIO
22/38
mA
IDDIO
3.3V Digital IO SW5-RMII + P5-RMII
VDDIO
39
mA
10BASE-T Operation —All Ports 100% Utilization
IDX
10BASE-T (Transmitter) 3.3V Analog
VDDAT
107
mA
IDda
10BASE-T 1.2V Analog
VDDAR
8.6
mA
IDDc
10BASE-T 1.2V Digital
VDDC
44
mA
IDDIO
10BASE-TX (Digital IO) Standalone 5-port
VDDIO
2.2
mA
IDDIO
3.3V Digital IO SW5-MII MAC/PHY + P5-MII
VDDIO
5/18
mA
IDDIO
3.3V Digital IO SW5-RMII + P5-RMII
VDDIO
29
mA
Auto-Negotiation Mode
IDX
10BASE-T (Transmitter) 3.3V Analog
VDDAT
55
mA
IDda
10BASE-T 1.2V Analog
VDDAR
22
mA
IEDM
10BASE-T 1.2V Digital
VDDC
46
mA
IDDIO
10BASE-T (Digital IO) Standalone 5-port
VDDIO
1.5
mA
Power Management Mode (Standalone)
IPSM1
Power Saving Mode 3.3V
VDDAT + VDDIO
35
mA
IPSM2
Power Saving Mode 1.2V
VDDAR + VDDC
55
mA
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
114
Revision-1.1
Symbol
Parameter
Condition
Min.
Typ.
Max.
Units
ISPDM1
Soft Power Down Mode 3.3V
VDDAT + VDDIO
2
mA
ISPDM2
Soft Power Down Mode 1.2V
VDDAR + VDDC
1.8
mA
IEDM1
Energy Detect Mode + PLL OFF 3.3V
VDDAT + VDDIO
5.5
mA
IEDM2
Energy Detect Mode + PLL OFF 1.2V
VDDAR + VDDC
1.5
mA
CMOS Inputs
VIH
Input High Voltage (VDDIO=3.3/2.5/1.8V)
2.0/1.8
/1.3
V
VIL
Input Low Voltage (VDDIO=3.3/2.5/1.8V)
0.8/0.7
/0.5
V
IIN
Input Current (Excluding Pull-up/Pull-down)
VIN = GND ~ VDDIO
–10
10
µA
CMOS Outputs
VOH
Output High Voltage (VDDIO=3.3/2.5/1.8V)
IOH = –8mA
2.4/2.0
/1.5
V
VOL
Output Low Voltage (VDDIO=3.3/2.5/1.8V)
IOL = 8mA
0.4/0.4
/0.3
V
IOZ
Output Tri-State Leakage
VIN = GND ~ VDDIO
10
µA
100BASE-TX Transmit (measured differentially after 1:1 transformer)
VO
Peak Differential Output Voltage
100Ω termination on the
differential output
0.95
1.05
V
VIMB
Output Voltage Imbalance
100Ω termination on the
differential output
2
%
tr tt
Rise/fall Time
3
5
ns
Rise/fall Time Imbalance
0
0.5
ns
Duty Cycle Distortion
±0.5
ns
Overshoot
5
%
Output Jitters
Peak-to-peak
0
0.75
1.4
ns
10BASE-T Receive
VSQ
Squelch Threshold
5MHz square wave
300
400
585
mV
10BASE-T Transmit (measured differentially after 1:1 transformer) VDDAT = 3.3V
VP
Peak Differential Output Voltage
100Ω termination on the
differential output
2.2
2.5
2.8
V
Output Jitters
Peak-to-peak
1.4
3.5
ns
Rise/fall Times
28
30
ns
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating. Unused inputs must always be tied to an appropriate logic voltage level (ground
or VDD).
3. No heat spreader in package. The thermal junction to ambient (θJA) and the thermal junction to case (θJC) are under air velocity 0m/s.
4. Specification for packaged product only. There is no an additional transformer consumption due to use on chip termination technology with internal
biasing for 10Bese-T and 100Base-TX.
5. Measurements were taken with operating ratings.
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
115
Revision-1.1
Timing Diagrams
EEPROM Timing
Figure 19. EEPROM Interface Input Receive Timing Diagram
Figure 20. EEPROM Interface Output Transmit Timing Diagram
Table 23. EEPROM Timing Parameters
Symbol
Parameter
Min.
Typ.
Max.
Units
tCYC1
Clock Cycle
16384
ns
tS1
Set-Up Time
20
ns
tH1
Hold Time
20
ns
tOV1
Output Valid
4096
4112
4128
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
116
Revision-1.1
SNI Timing
Figure 21. SNI Input Timing
Figure 22. SNI Output Timing
Table 24. SNI Timing Parameters
Symbol
Parameter
Min.
Typ.
Max.
Units
tCYC2
Clock Cycle
100
ns
tS2
Set-Up Time
10
ns
tH2
Hold Time
0
ns
tO2
Output Valid
0
3
6
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
117
Revision-1.1
MII Timing
Figure 23. MAC Mode MII Timing – Data Received from MII
Figure 24. MAC Mode MII Timing – Data Transmitted from MII
Table 25. MAC Mode MII Timing Parameters
10Base-T/100Base-TX
Symbol
Parameter
Min.
Typ.
Max.
Units
tCYC3
Clock Cycle
400/40
ns
tS3
Set-Up Time
10
ns
tH3
Hold Time
5
ns
tOV3
Output Valid
3
7
25
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
118
Revision-1.1
Figure 25. PHY Mode MII Timing – Data Received from MII
Figure 26. PHY Mode MII Timing – Data Transmitted from MII
Table 26. PHY Mode MII Timing Parameters
10BaseT/100BaseT
Symbol
Parameter
Min.
Typ.
Max.
Units
tCYC4
Clock Cycle
400/40
ns
tS4
Set-Up Time
10
ns
tH4
Hold Time
0
ns
tOV4
Output Valid
16
20
25
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
119
Revision-1.1
RMII Timing
Figure 27. RMII Timing – Data Received from RMII
Figure 28. RMII Timing – Data Transmitted to RMII
Table 27. RMII Timing Parameters
Timing Parameter
Description
Min.
Typ.
Max.
Unit
tcyc
Clock cycle
20
ns
t1
Setup time
4
ns
t2
Hold time
2
ns
tod
Output delay
3
14
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
120
Revision-1.1
SPI Timing
Figure 29. SPI Input Timing
Table 28. SPI Input Timing Parameters
Symbol
Parameter
Min.
Typ.
Max.
Units
fC
Clock Frequency
25
MHz
tCHSL
SPIS_N Inactive Hold Time
10
ns
tSLCH
SPIS_N Active Set-Up Time
10
ns
tCHSH
SPIS_N Active Hold Time
10
ns
tSHCH
SPIS_N Inactive Set-Up Time
10
ns
tSHSL
SPIS_N Deselect Time
20
ns
tDVCH
Data Input Set-Up Time
5
ns
tCHDX
Data Input Hold Time
5
ns
tCLCH
Clock Rise Time
1
µs
tCHCL
Clock fall Time
1
µs
tDLDH
Data Input Rise Time
1
µs
tDHDL
Data Input fall Time
1
µs
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
121
Revision-1.1
Figure 30. SPI Output Timing
Table 29. SPI Output Timing Parameters
Symbol
Parameter
Min.
Typ.
Max.
Units
fC
Clock Frequency
25
MHz
tCLQX
SPIQ Hold Time
0
0
ns
tCLQV
Clock Low to SPIQ Valid
15
ns
tCH
Clock High Time
18
ns
tCL
Clock Low Time
18
ns
tQLQH
SPIQ Rise Time
50
ns
tQHQL
SPIQ fall Time
50
ns
tSHQZ
SPIQ Disable Time
15
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
122
Revision-1.1
Auto-Negotiation Timing
Figure 31: Auto-Negotiation Timing
Table 30. Auto-Negotiation Timing Parameters
Symbols
Parameters
Min.
Typ.
Max.
Units
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 pulse
111
128
139
µs
Number of Clock/Data pulse per burst
17
33
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
123
Revision-1.1
MDC/MDIO Timing
Figure 32. MDC/MDIO Timing
Table 31. MDC/MDIO Typical Timing Parameters
Timing Parameter
Description
Min.
Typ.
Max.
Unit
tP
MDC period
400
ns
t1MD1
MDIO (PHY input) setup to rising edge of MDC
10
ns
tMD2
MDIO (PHY input) hold from rising edge of MDC
4
ns
tMD3
MDIO (PHY output) delay from rising edge of MDC
222
ns
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
124
Revision-1.1
Reset Timing
Figure 33. Reset Timing
Table 32. Reset Timing Parameters
Symbol
Parameter
Min.
Typ.
Max.
Units
tSR
Stable Supply Voltages to Reset High
10
ms
tCS
Configuration Set-Up Time
50
ns
tCH
Configuration Hold Time
50
ns
tRC
Reset to Strap-In Pin Output
50
ns
tvr
3.3V rise time
100
us
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
125
Revision-1.1
Reset Circuit Diagram
Micrel recommends the following discrete reset circuit as shown in Figure 34 when powering up the KS8895MQ device.
For the application where the reset circuit signal comes from another device (e.g., CPU, FPGA, etc), we recommend the
reset circuit as shown in Figure 35.
Figure 34. Recommended Reset Circuit
Figure 35. Recommended Circuit for Interfacing with CPU/FPGA Reset
At power-on-reset, R, C, and D1 provide the necessary ramp rise time to reset the Micrel device. The reset out
RST_OUT_n from CPU/FPGA provides the warm reset after power up.
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
126
Revision-1.1
Selection of Isolation Transformer(1)
One simple 1:1 isolation transformer is needed at the line interface. An isolation transformer with integrated common-
mode choke is recommended for exceeding FCC requirements at line side. Request to separate the center taps of RX/TX
at chip side. The following table gives recommended transformer characteristics.
Table 33. Transformer Selection Criteria
Characteristics Name
Value
Test Condition
Turns Ratio
1 CT : 1 CT
Open-Circuit Inductance (min.)
350µH
100mV, 100kHz, 8mA
Insertion Loss (max.)
1.1dB
0.1MHz to 100MHz
HIPOT (min.)
1500Vrms
Note: The IEEE 802.3u standard for 100BASE-TX assumes a transformer loss of 0.5dB. For the transmit line transformer, insertion loss of up to 1.3dB
can be compensated by increasing the line drive current by means of reducing the ISET resistor value.
The following transformer vendors provide compatible magnetic parts for Micrel’s device:
Table 34. Qualified Magnetic Vendors
Vendors and Parts
Auto
MDIX
Number
of Ports
Vendors and Parts
Auto
MDIX
Number of
Ports
Pulse
H1664NL
Yes
4
Pulse
H1102
Yes
1
Pulse
H1164NL
Yes
4
Bel Fuse
S558-5999-U7
Yes
1
TDK
TLA-6T718A
Yes
1
YCL
PT163020
Yes
1
LanKom
LF-H41S
Yes
1
Transpower
HB726
Yes
1
Datatronic
NT79075
Yes
1
Delta
LF8505
Yes
1
Selection of Reference Crystal
Table 35. Typical Reference Crystal Characteristics
Chacteristics
Value
Units
Frequency
25.00000
MHz
Frequency tolerance (max)
<= 50
ppm
Load capacitance (max)
27
pF
Series resistance (ESR)
40
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
127
Revision-1.1
Package Information
128-Pin PQFP Package
Micrel, Inc.
KSZ8895MQX/RQX/FQX/ML
April 28, 2014
128
Revision-1.1
128-Pin LQFP Package
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical
implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
© 2014 Micrel, Incorporated.
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Authorized Distributor
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