Transmitting 9-Bit Characters

The EUSART supports 9-bit character transmissions. When the 9-Bit Transmit Enable (TX9) bit is set, the EUSART will shift nine bits out for each character transmitted. The TX9D bit is the ninth and Most Significant data bit. When transmitting 9-bit data, the TX9D data bit must be written before writing the eight Least Significant bits into the TXxREG. All nine bits of data will be transferred to the TSR register immediately after the TXxREG is written.

A special 9-bit Address mode is available for use with multiple receivers. See Address Detection for more information on the Address mode.