SWRU543B January 2019 – June 2025 CC3230S , CC3230SF , CC3235MODS , CC3235MODSF , CC3235S , CC3235SF
The DMA read request line asserts when the channel is enabled, and the number of bytes defined in SPI_XFERLEVEL[AFL] bit field is held in the FIFO buffer for the receive register of the channel. A DMA read request can be individually masked with the DMAR bit of the SPI_CHCONF register. The DMA read request line is deasserted on the first SPI word read completion of the receive register of the channel. No new DMA request is asserted if the user has not performed the correct number of read accesses, as defined by SPI_XFERLEVEL[AFL].
The DMA write request line asserts when the channel is enabled, and the number of bytes held in the FIFO buffer is below the level defined by the SPI_XFERLEVEL[AEL] bit field. A DMA write request can be individually masked with the DMAW bit of the SPI_CHCONF register.