25.3.2.3.2 Disabling the Transmitter

A disabling of the transmitter will not become effective until ongoing and pending transmissions are completed; I.e., when the Transmit Shift register and Transmit Buffer register do not contain data to be transmitted. When the transmitter is disabled, it will no longer override the TxDn pin, and the PORT module regains control over the pin. To protect external circuitry the pin is automatically configured as an input by hardware. The pin can now be used as a normal I/O pin with no port override from the USART.