
Micrel, Inc.
KSZ8842-PMQL/PMBL
October 2007
86
M9999-100207-1.5
Bit
Default
R/W
Description
8
0
RW
Learning disable
1 = disable switch address learning capability
0 = enable switch address learning
7
0
RW
Sniffer port
1 = Port is designated as sniffer port and will transmit packets that are
monitored.
0 = Port is a normal port
6
0
RW
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
5
0
RW
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
4
0
RW
Reserved
3
0
R/W
User Priority Field
1 = if the packet’s “user priority field” is greater than the “user priority bits”
in port 2’s VID Control register bits [15:13], replace the packet’s “user
priority field” with the “user priority bits” in port 2’s VID Control register bits
[15:13].
0 = do not compare and replace the packet’s ‘user priority field”
2 – 0
111
RW
Port VLAN membership
Define the port’s Port VLAN membership. Bit 2 stands for port 3, bit 1 for
port 2, and bit 0 for port 1. The Port can only communicate within the
membership. An ‘1’ includes a port in the membership; an ‘0’ excludes a
port from the membership.
Port 2 VID Control Register (Offset 0x0524): P2VIDCR
This register contains the global per port control for the switch port 2 function.
Bit
Default
R/W
Description
15 – 13
000
RW
User Priority bits
Port 2 tag [15-13] for priority
12
0
RW
CFI bit
Port 2 tag [12] for CFI
11 – 0
0x001
RW
VID bits
Port 2 tag [11-0] for VID
Note: P2VIDCR 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.