Description of Operation
8-14
ADSP-BF537 Blackfin Processor Hardware Reference
The address filter is evaluated in the following sequence. Note that this
sequence is in the same order as the related bits in the operating mode reg-
ister, from LSB to MSB:
HU
,
HM
,
PAM
,
PR
,
IFE
, and
DBF
. The first few filter
decisions are additive, while the last two are subtractive.
1. Initially, the address filter is true if the frame’s MAC destination
address (DA) is either the broadcast address (all 1s) or exactly
matches the 48-bit station MAC address in the
EMAC_ADDRHI
and
EMAC_ADDRLO
registers.
2.
HU (hash unicast)
– If the
HU
bit is 1 and the DA is a unicast
address which matches the hash table, the address filter is set to
true.
3.
HM (hash multicast)
– If the
HM
bit is 1 and if the DA is a multi-
cast address which matches the hash table, the address filter is set to
true.
4.
PAM (pass all multicast)
– If the
PAM
bit is 1 and the DA is any
multicast address, the address filter is set to true.
5.
PR (promiscuous)
– If the
PR
bit is 1, the address filter is set to true
regardless of the frame DA.
6.
FLCE (flow control enable)
– If the
FLCE
bit in the flow control
register is 1, and if the DA is an exact match to either the global
multicast pause address or to the station MAC address, the address
filter is set to true.
7.
IFE (inverse filter)
– If the
IFE
bit is 1 and the DA exactly matches
the 48-bit station MAC address, the address filter is set to false.
8.
DBF (disable broadcast frames)
– If the
DBF
bit is 1 and the DA is
the broadcast address, the address filter is set to false.
The hash table address filtering is configured with the
EMAC_HASHLO
and
EMAC_HASHHI
registers described
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...