30.1.1.1 Enabling the Transmitter
The EUSART transmitter is enabled for asynchronous operations by configuring the following three control bits:
- The Transmit Enable (TXEN) bit is set to ‘
1
’ to enable the transmitter circuitry of the EUSART - The EUSART Mode Select (SYNC) bit is set to ‘
0
’ to configure the EUSART for asynchronous operation - The Serial Port Enable (SPEN) bit is set to ‘
1
’ to enable the EUSART interface and to enable automatically the output drivers for the RxyPPS selected as the TXx/CKx output
All other EUSART control bits are assumed to be in their default state.
If the TXx/CKx pin is shared with an analog peripheral, the analog I/O function must be disabled by clearing the corresponding ANSEL bit.
Important: The TXxIF Transmitter Interrupt Flag in the PIRx
register is set when the TXEN enable bit is set and the Transmit Shift Register (TSR) is
Idle.