External Port DMA
3-104 ADSP-214xx SHARC Processor Hardware Reference
Chained DMA Mode
Chained DMA is used to support repetitive reads and writes to a specific
area which is defined by the individual TCBs.
Changing DMA Direction on the Fly
The SHARC processors allow a change of external port data direction for
each individual TCB in a chain sequence.
Figure 3-22. Circular Buffering Write DMA
Figure 3-23. Circular Buffering Read DMA
20
19
18
3
2
1
1
2
17
16
DESTINATION INDEX
(IIEP)
SOURCE INDEX
(IIEP)
DESTINATION BUFFER
SOURCE BUFFER
17
20
19
18
DESTINATION BASE
ADDRESS (EBEP)
20
19
18
3
2
1
1
2
17
16
DESTINATION INDEX
(IIEP)
SOURCE INDEX
(EIEP)
DESTINATION BUFFER
SOURCE BUFFER
17
20
19
18
SOURCE BASE
ADDRESS (EBEP)