General - 7.2 English

AXI 1G/2.5G Ethernet Subsystem Product Guide (PG138)

Document ID
PG138
Release Date
2023-11-15
Version
7.2 English

The TEMAC core provides up to four multicast addresses that can be specified for receive address validation (if an incoming multicast frame receive address matches one of the four specified addresses, it is accepted). More multicast address values can be used by operating in promiscuous mode with software application filtering.

Extended multicast filtering is included at build time by setting the C_MCAST_EXTEND parameter to 1. This provides additional logic for address filtering. The TEMAC core prevents receiving any multicast frames if they do not match one of the four entries in the built-in multicast address table. As a result, the TEMAC core has to be placed in promiscuous mode to force it to pass all multicast frames through to the extended multicast address filtering logic.

TEMAC in promiscuous mode will also pass through all unicast address frames. To avoid increasing the processor load for unicast address filtering, additional unicast address filtering has to be added to the extended multicast address filtering logic. Ensure that the TEMAC core is in promiscuous receive address mode when using this extended multicast address filtering mode.