
Data Transfer
8-12
ADSP-214xx SHARC Processor Hardware Reference
For ping-pong DMA mode, transmit and receive for all data types are
handled in the following manner.
• At the start of buffer processing, the beginning of the next buffer
becomes the beginning of the current buffer, as the
BSA
bits from
the
MLB_CNBCRx
register are loaded into the
BCA
bit field of the
MLB_CCBCRx
register. Additionally, the end of the next buffer
becomes the end of the current buffer, as the
BEA
bit field from the
MLB_CNBCRx
register is loaded into the
BFA
bit field of the
MLB_CCBCRx
register.
• A current buffer start interrupt is generated (
STS
bit in the
MLB_CSCRx
register), which informs the software that hardware has
updated the
MLB_CCBCRn
register, cleared the local channel
RDY
bit,
and is available to accept the next buffer. Software may then pre-
pare the next buffer by writing:
BSA
,
BEA
, and
RDY
bits.
• During the processing of the current buffer,
BCA
bits continue to
mark which quadlet of data or packet is currently being processed.
• A current buffer done interrupt is generated when the last quadlet
in the current buffer has been successfully transmitted/received.
The current buffer and the next buffer can be configured for either
multi-packet or single-packet buffering, when receiving and transmitting
asynchronous and control packet data.
• Multi-packet buffering allows the system to reduce the interrupt
load at the expense of larger DMA buffers.
• Single-packet buffering allows DMA buffer size to be reduced at
the expense of increasing the interrupt rate.
For more information, see “Programming Model” on page 8-16.
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Summary of Contents for SHARC ADSP-214 Series
Page 60: ...Contents lx ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 72: ...Notation Conventions lxxii ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 130: ...Programming Model 2 52 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 264: ...Programming Models 3 134 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 290: ...Programming Model 4 26 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 296: ...Programming Model 5 6 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 396: ...Effect Latency 7 28 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 520: ...Programming Model 10 62 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 616: ...Debug Features 14 22 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 656: ...Programming Model 15 40 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 714: ...Programming Model 19 10 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 1132: ...Register Listing A 306 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Page 1192: ...Index I 34 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...