SFFS948 May 2025 MSPM0L1227-Q1 , MSPM0L1228-Q1 , MSPM0L2227-Q1 , MSPM0L2228-Q1
The UART can be placed into an internal loopback mode for diagnostic or debug work by setting the LBE bit in the UART.CTL0 register. In loopback mode, data transmitted on the TXD output is received on the RXD input. Data received on the RXD I/O pin is ignored when loopback is enabled. A timer can be used to check if the communication completed within the expected amount of time.