Asynchronous Transmission Setup
- 1.Initialize the SPxBRGH, SPxBRGL register pair and the BRGH and
BRG16 bits to achieve the desired baud rate (see EUSART Baud Rate Generator (BRG)).
- 2.Select the transmit output pin by writing the appropriate value to the RxyPPS
register.
- 3.Enable the asynchronous serial port by clearing the SYNC bit and setting the SPEN bit.
- 4.If 9-bit transmission is desired, set the TX9 control bit. A set ninth data bit will indicate that the eight Least Significant data bits are an address when the receiver is set for address detection.
- 5.Set SCKP bit if inverted transmit is desired.
- 6.Enable the transmission by setting the TXEN control bit. This will cause the TXxIF interrupt bit to be set.
- 7.If interrupts are desired, set the TXxIE interrupt enable bit of
the PIEx register
- 8.An interrupt will occur immediately provided that the GIE and
PEIE bits of the INTCON register are also set.
- 9.If 9-bit transmission is selected, the ninth bit should be loaded into the TX9D data bit.
- 10.Load 8-bit data into the TXxREG register. This will start the transmission.
Figure 1. Asynchronous Transmission
Figure 2. Asynchronous Transmission
(Back-to-Back)