Interrupt Mask Register
| RXRDY | RXRDY Interrupt Mask |
| TXRDY | TXRDY Interrupt Mask |
| RXBRK | Receiver Break Interrupt Mask |
| ENDRX | End of Receive Buffer Interrupt Mask (available in all USART modes of operation) |
| ENDTX | End of Transmit Buffer Interrupt Mask (available in all USART modes of operation) |
| OVRE | Overrun Error Interrupt Mask |
| FRAME | Framing Error Interrupt Mask |
| PARE | Parity Error Interrupt Mask |
| TIMEOUT | Time-out Interrupt Mask |
| TXEMPTY | TXEMPTY Interrupt Mask |
| ITER | Max Number of Repetitions Reached Interrupt Mask |
| TXBUFE | Transmit Buffer Empty Interrupt Mask (available in all USART modes of operation) |
| RXBUFF | Receive Buffer Full Interrupt Mask (available in all USART modes of operation) |
| NACK | Non Acknowledge Interrupt Mask |
| RIIC | Ring Indicator Input Change Mask |
| DSRIC | Data Set Ready Input Change Mask |
| DCDIC | Data Carrier Detect Input Change Interrupt Mask |
| CTSIC | Clear to Send Input Change Interrupt Mask |
| MANE | Manchester Error Interrupt Mask |