AT91RM9200_06 Datasheet, PDF (603/689 Pages) ATMEL Corporation – ARM920T-based Microcontroller

AT91RM9200
active address, the local match signal is set and the store frame pulse signal is sent to the DMA
block via the HCLK synchronization block.
A frame can also be copied if a unicast or multicast hash match occurs, it has the broadcast
address of all ones, or the copy all frames bit in the network configuration register is set.
The broadcast address of 0xFFFFFFFF is recognized if the no broadcast bit in the network con-
figuration register is zero. This sets the broadcast match signal and triggers the store frame
signal.
The unicast hash enable and the multicast hash enable bits in the network configuration register
enable the reception of hash matched frames. So all multicast frames can be received by setting
all bits in the hash register.
The CRC algorithm reduces the destination address to a 6-bit index into a 64-bit hash register.If
the equivalent bit in the register is set, the frame is matched depending on whether the frame is
multicast or unicast and the appropriate match signals are sent to the DMA block. If the copy all
frames bit is set in the network configuration register, the store frame pulse is always sent to the
DMA block as soon as any destination address is received.
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