ADSP-BF537 Blackfin Processor Hardware Reference
8-11
Ethernet MAC
functions while station management transfers are in progress. Alterna-
tively, the processor may determine the status of the transfer in progress
by reading the
STABUSY
bit in the
EMAC_STAADD
register.
Receive DMA Operation
Data flow between the MAC and the Blackfin peripheral subsystem takes
place via bidirectional descriptor based DMA. The element size for any
DMA transfer to and from the Ethernet MAC is restricted to 32 bits. In
the receive case, a queue or ring of DMA descriptor pairs are used, as illus-
trated in
. In the figure, data descriptors are labeled with an “A”
and status descriptors are labeled with a “B.”
Figure 8-5. Ethernet MAC Receive DMA Operation
XXXX
Active DMA Descriptor
ActiveQueueEnd
DONE
NOT DONE
1A
DATA
DESCRIPTORS:
ActiveQueueHead
1B
2A
2B
3A
3B
END
0000
0000
NOT DONE
DATA
DATA
STATUS BUFFERS:
DATA BUFFERS:
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 ...