Specifications

Micrel, Inc.
KSZ8895MQ/RQ/FMQ
Global Registers (Continued)
Address Name Description Mode Default
4
Enable Pre-Tag on
Switch SW5-MII/RMII
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.
March 12, 2014
60
Revision 1.7