KSZ8893M Datasheet, PDF (93/116 Pages) Micrel Semiconductor – Integrated 3-Port 10/100 Managed Switch with PHYs

Micrel, Inc.
KSZ8893MQL/MBL
Static MAC Address Table
The KSZ8893MQL/MBL supports both a static and a dynamic MAC address table. In response to a Destination
Address (DA) look up, the KSZ8893MQL/MBL searches both tables to make a packet forwarding decision. In
response to a Source Address (SA) look up, only the dynamic table is searched for aging, migration and learning
purposes.
The static DA look up result takes precedence over the dynamic DA look up result. If there is a DA match in both
tables, the result from the static table is used. The entries in the static table will not be aged out by the
KSZ8893MQL/MBL.
The static table is accessed by a external processor via the SMI, SPI or I²C interfaces. The external processor
performs all addition, modification and deletion of static MAC table entries.
Bit
57-54
53
52
51
50-48
47-0
Name
R/W
FID
R/W
Use FID
R/W
Override
R/W
Valid
R/W
Forwarding
R/W
Ports
MAC Address R/W
Description
Filter VLAN ID – identifies one of the 16 active VLANs
= 1, use (FID+MAC) for static table look ups
= 0, use MAC only for static table look ups
= 1, override port setting “transmit enable=0” or
“receive enable=0” setting
= 0, no override
= 1, this entry is valid, the lookup result will be used
= 0, this entry is not valid
These 3 bits control the forwarding port(s):
001, forward to port 1
010, forward to port 2
100, forward to port 3
011, forward to port 1 and port 2
110, forward to port 2 and port 3
101, forward to port 1 and port 3
111, broadcasting (excluding the
ingress port)
48-bit MAC Address
Default
0000
0
0
0
000
0x0000_0
000_0000
Table 16. Format of Static MAC Table (8 Entries)
Examples:
1. Static Address Table Read (Read the 2^nd Entry)
Write to reg. 121 (0x79) with 0x10
Write to reg. 122 (0x7A) with 0x01
Then,
Read reg. 124 (0x7C), static table bits [57:56]
Read reg. 125 (0x7D), static table bits [55:48]
Read reg. 126 (0x7E), static table bits [47:40]
Read reg. 127 (0x7F), static table bits [39:32]
Read reg. 128 (0x80), static table bits [31:24]
Read reg. 129 (0x81), static table bits [23:16]
Read reg. 130 (0x82), static table bits [15:8]
Read reg. 131 (0x83), static table bits [7:0]
// Read static table selected
// Trigger the read operation
February 2010
93
M9999-021110-1.6