SPMU447 June 2026 CC2755P20
All other audio interface-related register configuration (pins, serial format, clocks, sample word sizes, and channel mapping) must be completed before writing a nonzero value to the AIFDMACFG.END_FRAME_IDX register. To prepare input and output DMA for start-up, the software must preload the first and second DMA pointers to be used and must arm the DMA:
Write the first memory block start addresses to be used to AIFINPTRNEXT and (or) AIFOUTPTRNEXT
Set AIFDMACFG.END_FRAME_IDX = the number of frames per block minus one.
This loads AIFINPTRNEXT into AIFINPTR, and AIFOUTPTRNEXT into AIFOUTPTR, and the output DMA will immediately prefetch sample words for the first two audio channels.
Write the second memory block start addresses to be used to AIFINPTRNEXT and (or) AIFOUTPTRNEXT.