SPRUIZ1B July 2023 – August 2024 TMS320F28P650DH , TMS320F28P650DK , TMS320F28P650SH , TMS320F28P650SK , TMS320F28P659DH-Q1 , TMS320F28P659DK-Q1 , TMS320F28P659SH-Q1
The UART can be placed into an internal loopback mode for diagnostic or debug work by setting the LBE bit in the UARTCTL register. In loopback mode, data transmitted on the UnTx output is received on the UnRx input. Note that the LBE bit must be set before the UART is enabled.