Chained Dma Transfers - Analog Devices ADSP-21261 SHARC Hardware Reference Manual

Programming Model
bytes may not be received by the SPI DMA due to the condition for gen-
erating the DMA request.
To configure for slave mode DMA:
1. Write to the
the same as the mode that is set up in the SPI master. Configure
the
TIMOD
( = 10).
TIMOD
2. Define DMA receive (or transmit) transfer parameters by writing
to the
IISPIx
write to the chain pointer address of the
3. Write to the
configure the following:
• A receive access (
• A transmit access (
If DMA chaining is desired, set the
SPIDMACx

Enable the SPI port before enabling DMA to avoid data
corruption.

Chained DMA Transfers

The sequence for setting up and starting a chained DMA is outlined in the
following steps.
1. Clear the chain pointer register.
2. Configure the TCB associated with each DMA in the chain except
for the first DMA in the chain.
10-48
register to make the mode of the serial link
SPICTLx
field to select transmit or receive DMA mode
, , and
IMSPIx CSPIx
registers to enable the SPI DMA engine and
SPIDMACx
SPIRCV
SPIRCV
registers.
ADSP-2126x SHARC Processor Hardware Reference
registers. For DMA chaining,
registers.
CPSPIx
= 1) or
= 0)
SPICHEN
bit in the