Modes Of Operation; Register-Based Dma Operation - Analog Devices Blackfin ADSP-BF537 Hardware Reference Manual

Modes of Operation

Modes of Operation
The following sections describe the DMA operation.

Register-based DMA Operation

Register-based DMA is the traditional kind of DMA operation. Software
writes source or destination address and length of the data to be trans-
ferred into memory-mapped registers and then starts DMA operation.
For basic operation the software performs these steps:
• Write the source or destination address to the 32-bit
register.
ADDR
• Write the number of data words to be transferred to the 16-bit
DMAx_X_COUNT
• Write the address modifier to the 16-bit
This is the two's-complement value added to the address pointer
after every transfer. This value must always be initialized as there is
no default value. Typically, this register is set to
DMA transfers, to
byte transfers.
5-12
register.
for 16-bit transfers, and to
0x0002
ADSP-BF537 Blackfin Processor Hardware Reference
DMAx_START_
register.
DMAx_X_MODIFY
for 32-bit
0x0004
0x0001
for