ADSP-2126x SHARC Processor Hardware Reference
10-23
Serial Peripheral Interface Port
With disabling of the SPI:
1. Write 0x00 to the
SPICTL
register to disable SPI. Disabling SPI also
clears the
RXSPI
/
TXSPI
register contents and the buffer status.
2. Disable DMA and clear the DMA FIFO by writing 0x80 to the
SPIDMAC
register. This ensures that any data from a previous DMA
operation is cleared because the
SPICLK
signal runs for five more
word transfers even after the DMA count falls to zero in receive
DMA.
3. Clear all errors by writing to the
SPISTAT
register. This ensures that
no interrupts occur due to errors from a previous DMA operation.
4. Reconfigure the
SPICTL
register and enable SPI.
5. Configure DMA by writing to the DMA parameter registers and
the
SPIDMAC
register.
Without disabling the SPI:
1. Clear
RXSPI
/
TXSPI
without disabling the SPI. This can be done by
ORing 0xc0000 with the present value in the
SPICTL
register. Use
the
RXFLSH
(bit 19) and
TXFLSH
(bit 18 in the
SPICTL
register) bits
to clear the
RXSPI/TXSPI
registers.
2. Disable DMA and clear the FIFO. For example, write 0x80 to the
SPIDMAC
register. This ensures that any data from a previous DMA
operation clears because the
SPICLK
runs for five more word trans-
fers even after the DMA count is zero in receive DMA.
3. 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.
Summary of Contents for ADSP-21261 SHARC
Page 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Page 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Page 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Page 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Page 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Page 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Page 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Page 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Page 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Page 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Page 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Page 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...