ksz8893mqlam Micrel Semiconductor, ksz8893mqlam Datasheet - Page 41

• Manufacturer Part Number: ksz8893mqlam
• Description: Integrated 3-port 10/100 Managed Switch With Phys
• Manufacturer: Micrel Semiconductor

The KSZ8893MQL/MBL filters error frames, and thus does not implement the RX_ER output signal. To detect
error frames from RMII PHY devices, the SMTXER input signal of the KSZ8893MQL/MBL is connected to the
RXER output signal of the RMII PHY device.
Collision detection is implemented in accordance with the RMII Specification.
In RMII mode, tie MII signals, SMTXD[3:2] and SMTXER, to ground if they are not used.
The KSZ8893MQL/MBL RMII can interface with RMII PHY and RMII MAC devices. The latter allows two
KSZ8893MQL/MBL devices to be connected back-to-back. The following table shows the KSZ8893MQL/MBL
RMII pin connections with an external RMII PHY and an external RMII MAC, such as another KSZ8893MQL/MBL
device.
SNI (7-Wire) Operation
The serial network interface (SNI) or 7-wire is compatible with some controllers used for network layer protocol
processing. In SNI mode, the KSZ8893MQL/MBL acts like a PHY and the external controller functions as the
MAC. The KSZ8893MQL/MBL can interface directly with external controllers using the 7-wire interface. These
signals are divided into two groups, one for transmission and the other for reception. The signals involved are
described in the following table.
December 2007
External
PHY Signals
REF_CLK
CRS_DV
RXD1
RXD0
TX_EN
TXD1
TXD0
RX_ER
KSZ8893MQL/MBL
PHY-MAC Connections
Pin Descriptions
Transmit enable
Serial transmit data
Transmit clock
Collision detection
Carrier sense
Serial receive data
Receive clock
KSZ8893MQL/M
BL
MAC Signals
REFCLK
SMRXDV
SMRXD[1]
SMRXD[0]
SMTXEN
SMTXD[1]
SMTXD[0]
SMTXER
Table 5: RMII Signal Connections
Pin
Descriptions
Reference Clock
Carrier sense/
Receive data valid
Receive data bit 1
Receive data bit 0
Transmit enable
Transmit data bit 1
Transmit data bit 0
Receive error
Table 6. SNI Signals
External MAC
Controller Signals
TXEN
TXD
TXC
COL
CRS
RXD
RXC
41
KSZ8893MQL/MBL
PHY Signals
SMTXEN
SMTXD[0]
SMTXC
SCOL
SMRXDV
SMRXD[0]
SMRXC
KSZ8893MQL/MBL
MAC-MAC Connections
KSZ8893MQL/M
BL
MAC Signals
REFCLK
SMRXDV
SMRXD[1]
SMRXD[0]
SMTXEN
SMTXD[1]
SMTXD[0]
(not used)
External
MAC Signals
REF_CLK
CRS_DV
RXD1
RXD0
TX_EN
TXD1
TXD0
(not used)
M9999-121007-1.5