SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
If a collision occurs at the MAC application interface while the TX/RX Controller is transferring data to the MAC, the transmission is aborted and the MAC indicates a retry attempt by giving a collision status before the EOF is transferred to the TX/RX Controller from the DMA. This enables the TX/RX Controller to retry transmission of the frame data from the FIFO.
After more than 96 bytes are transferred to the MAC, the FIFO controller clears space in the FIFO and makes it available to the DMA to transfer more data. Retransmission is not possible after this threshold is crossed or when the MAC indicates a late collision event.
When a frame transmission is aborted because of underflow and a collision event follows, which initiates a retry, then the retry has higher priority than the abort.