ADSP-214xx SHARC Processor Hardware Reference
15-35
Serial Peripheral Interface Ports
With enabled SPI:
1. Poll the
SPIFE
bit in the
SPISTAT
register. If this bit is high the SPI
buffer can be cleared.
2. Clear the
RXSPIx
/
TXSPIx
buffers and the buffer status without dis-
abling the SPI. This can be done by ORing 0xC0000 with the
present value in the
SPICTLx
register. For example, programs can
use the
RXFLSH
and
TXFLSH
bits to clear
TXSPIx
/
RXSPIx
and the buf-
fer status.
3. Clear the
SPIDMAC
register.
4. Clear all errors by writing to the W1C-type bits in the
SPISTAT
reg-
ister. This ensures that no interrupts occur due to errors from a
previous DMA operation.
5. Reconfigure the
SPICTL
register to remove the clear condition on
the
TXSPI
/
RXSPI
registers.
6. Configure DMA by writing to the DMA parameter registers and
the
SPIDMACx
registers using the
SPIDEN
bit (bit 0).
Switching From Receive to a New DMA
Use the following sequence to switch from receive to transmit DMA. Note
that
TXSPIx
and
RXSPIx
are registers but they may not contain any bits,
only address information.
With disabled SPI:
1. Poll the
SPIFE
bit in the
SPISTAT
register. If this bit =1 the SPI can
be disabled.
2. Clear the
SPICTLx
registers to disable the SPI. Disabling the SPI
also clears the
RXSPIx
/
TXSPIx
register contents and the buffer
status.
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Содержание SHARC ADSP-214 Series
Страница 60: ...Contents lx ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 72: ...Notation Conventions lxxii ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 130: ...Programming Model 2 52 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 264: ...Programming Models 3 134 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 290: ...Programming Model 4 26 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 296: ...Programming Model 5 6 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 396: ...Effect Latency 7 28 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 520: ...Programming Model 10 62 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 616: ...Debug Features 14 22 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 656: ...Programming Model 15 40 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 714: ...Programming Model 19 10 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 1132: ...Register Listing A 306 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 1192: ...Index I 34 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...