SLAU962A December 2025 – June 2026 MSPM33C321A , MSPM33C321A-Q1
The STAT register contains empty and full flags (TXFE, TXFF, RXFE, and RXFF bits), and the RIS register shows the overflow status of the receive FIFO via the RXFIFO_OVF bit. There is no indicator for a transmit FIFO overflow. A write is just lost if it overflows the transmit FIFO. If the FIFOs are not present, the empty and full flags are set according to the status of the 1-byte-deep holding registers.
Out of reset, both FIFOs are configured to trigger an interrupt at half-level mark.