37.6.8.1 DMA Operation

Each Serializer can be connected either to one single DMAC channel or to one DMAC channel per data slot in Stereo mode. This is selected by writing the RXCTRL/TXCTRL.DMA bit.
Table 37-3. I2C DMA Request Generation
SERCTRLm.DMA Mode Slot Parity DMA Request Trigger
0 Receiver all I2S_DMAC_ID_RX_m
Transmitter all I2S_DMAC_ID_TX_m
1 Receiver even I2S_DMAC_ID_RX_m
odd I2S_DMAC_ID_TX_m
Transmitter even I2S_DMAC_ID_TX_m
odd I2S_DMAC_ID_RX_m

The DMAC reads from the RXDATA register and writes to the TXDATA register for all data slots, successively.

The DMAC transfers may use 32-bit, 16-bit, or or 8-bit transactions according to the value of the TXCTRL/RXCTRL.DATASIZE field. 8-bit compact stereo uses 16-bit and 16-bit compact stereo uses 32-bit transactions.