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IP178C/IP178C LF/IP178CH/IP178CH LF
Datasheet
46/93
June 21, 2007
Copyright © 2004, IC Plus Corp.
IP178Cx-DS-R12
2.11
Static MAC address table
User can setup the static MAC address table to force the switching behavior of IP178C/IP178CH by
programming MII register 31.14 ~ 30.21. When IP178C/IP178CH receives packets, which match
pre-defined MAC address in the table (static_mac_0, static_mac_1), it forwards the packet to MII port
(CPU). The static MAC address table has precedence over the dynamic DA look up result.
In a spanning tree application, the MII register 31.17[10] static_override_0 is “1”, MII register 31.17[9]
static_valid_0 is ”1”, the MII register 31.14~31.16 MAC address field is 01-80-c2-00-00-00 and the MII
register 31.17[8:0] static_port_mask_0 is 9’b1_0000_0000 (MII). That is, IP178C/IP178CH only forwards
BPDU to MII (CPU) and in spite of the port states.
MII register
R/W
Description
Default
31.17.10
R/W override_0
1: override the transmission, receiving and learning setting
in MII register 31.13.
0: not override
1
31.17.9
R/W state_valid_0
1: the entry is valid
0: the entry is not valid
0
31.17[8:0]
R/W state_port_mask_0
Bit 8: forward to port 8 (MII)
Bit 7: forward to port 7
Bit 6: forward to port 6
Bit 5: forward to port 5
Bit 4: forward to port 4
Bit 3: forward to port 3
Bit 2: forward to port 2
Bit 1: forward to port 1
Bit 0: forward to port 0
9’b1_0000_0000
31.14 – 16
R/W state_mac_0
01-80-C2-00-00-00