KSZ8895MQ_12 MICREL [Micrel Semiconductor], KSZ8895MQ_12 Datasheet - Page 36

• Manufacturer Part Number: KSZ8895MQ_12
• Description: Integrated 5-Port 10/100 Managed Ethernet Switch with MII/RMII interface
• Manufacturer: MICREL [Micrel Semiconductor]

Micrel, Inc.
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 KSZ8895MQ/RQ/FMQ 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 KSZ8895MQ/RQ/FMQ 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 KSZ8895MQ/FMQ support P5-MII, the KSZ8895RQ 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.
March 2012
MRXDV
MRXER
MTXEN
MTXER
MRXD3
MRXD2
MRXD1
MRXD0
MTXD3
MTXD2
MTXD1
MTXD0
Signal
MCRS
MRXC
MTXC
MCOL
MII
Transmit data bit 3
Transmit data bit 2
Transmit data bit 1
Transmit data bit 0
Collision detection
Receive data valid
Receive data bit 3
Receive data bit 2
Receive data bit 1
Receive data bit 0
Transmit enable
Transmit clock
Transmit error
Receive clock
Carrier sense
Receive error
Description
KSZ8895MQ/FMQ
Table 3. Port 5 PHY P5-MII/RMII Signals
PMRXD[3]
PMRXD[2]
PMRXD[1]
PMRXD[0]
PMTXD[3]
PMTXD[2]
PMTXD[1]
PMTXD[0]
PMRXDV
PMRXER
PMTXEN
PMTXER
PMRXC
PMTXC
P5-MII
PCRS
PCOL
36
KSZ8895MQ/FMQ MII
Signal Type
O
O
O
O
O
O
O
O
O
O
I
I
I
I
I
I
PMREFCLK/PMTXC
KSZ8895RQ
PMRXD[1]
PMRXD[0]
PMTXD[1]
PMTXD[0]
PMRXDV
PMRXER
PMTXEN
P5-RMII
PMRXC
KSZ8895MQ/RQ/FMQ
M9999-032612-1.5
KSZ8895RQ
RMII Signal
Type
O
O
O
O
O
I
I
I
I