Datasheet

 2017 Microchip Technology Inc. DS00002348A-page 69
KSZ8873MLL/FLL/RLL
Examples:
1. Static Address Table Read (Read the 2nd Entry)
Write to reg. 121 (0x79) with 0x10 // Read static table selected
Write to reg. 122 (0x7A) with 0x01 // Trigger the read operation
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]
2. Static Address Table Write (Write the 8th Entry)
Write to reg. 124 (0x7C), static table bits [57:56]
Write to reg. 125 (0x7D), static table bits [55:48]
Write to reg. 126 (0x7E), static table bits [47:40]
Write to reg. 127 (0x7F), static table bits [39:32]
Write to reg. 128 (0x80), static table bits [31:24]
Write to reg. 129 (0x81), static table bits [23:16]
Write to reg. 130 (0x82), static table bits [15:8]
Write to reg. 131 (0x83), static table bits [7:0]
Write to reg. 121 (0x79) with 0x00 // Write static table selected
Write to reg. 122 (0x7A) with 0x07 // Trigger the write operation
4.7 VLAN Table
The KSZ8873 uses the VLAN table to perform look ups. If 802.1Q VLAN mode is enabled (register 5, bit 7 = 1), this
table will be used to retrieve the VLAN information that is associated with the ingress packet. This information includes
FID (filter ID), VID (VLAN ID), and VLAN membership as described in Table 4 - 11 .
If 802.1Q VLAN mode is enabled, KSZ8873 will assign a VID to every ingress packet. If the packet is untagged or tagged
with a null VID, the packet is assigned with the default port VID of the ingress port. If the packet is tagged with non-null
VID, the VID in the tag will be used. The look up process will start from the VLAN table look up. If the VID is not valid,
the packet will be dropped and no address learning will take place. If the VID is valid, the FID is retrieved. The FID+DA
TABLE 4-11: FORMAT OF STATIC VLAN TABLE (16 ENTRIES)
Bit Name R/W Description Default
19 Valid R/W
1 = entry is valid
0 = entry is invalid
1
18-16 Membership R/W
Specify which ports are members of the VLAN. If a DA
lookup fails (no match in both static and dynamic
tables), the packet associated with this VLAN will be
forwarded to ports specified in this field. For example,
101 means port 3 and 1 are in this VLAN.
111
15-12 FID R/W
Filter ID. KSZ8873 supports 16 active VLANs repre-
sented by these four bit fields. FID is the mapped ID.
If 802.1Q VLAN is enabled, the look up will be based
on FID+DA and FID+SA.
0x0
11-0 VID R/W IEEE 802.1Q 12 bits VLAN ID 0x001