Specifications

Micrel, Inc.
KSZ8895MQ/RQ/FMQ
Static MAC Address Table
KSZ8895MQ/RQ/FMQ 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 KSZ8895MQ/RQ/FMQ. 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.
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
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
Table 15. Static MAC Address Table
March 12, 2014
92
Revision 1.7