SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
The arbiter inside the DMA module performs the arbitration between the Transmit and Receive channel accesses. The DMA can be configured to arbitrate in a round-robin or fixed-priority configuration. When the DA bit of the EMACDMABUSMOD register is clear, the DMA arbiter allocates the data bus in the ratio set by the PR bit field of the EMACDMABUSMOD register when both the TX and RX DMA request access at the same time. When the DA bit is set, the RX DMA always has priority over the TX DMA for data access by default. However if the TXPR bit of the EMACDMABUSMOD register is also set, then the TX DMA always gets priority over the RX DMA.