Микроконтроллеры PIC

первой в настройках порта всегда идет команда отключения модуля SPEN = 0; потом всё по пунктам из мануала 1. Initialize the SPBRGH:SPBRG register pair and the BRGH and BRG16 bits to achieve the desired baud rate (see Section 16.3 “EUSART Baud Rate Generator (BRG)”). 2. Enable the serial port by setting the SPEN bit and the RX/DT pin TRIS bit. The SYNC bit must be clear for asynchronous operation. 3. If interrupts are desired, set the RCIE interrupt enable bit and set the GIE and PEIE bits of the INTCON register. 4. If 9-bit reception is desired, set the RX9 bit. 5. Set the DTRXP if inverted receive polarity is desired. 6. Enable reception by setting the CREN bit. 7. The RCIF interrupt flag bit will be set when a character is transferred from the RSR to the receive buffer. An interrupt will be generated if the RCIE interrupt enable bit was also set. 8. Read the RCSTA register to get the error flags and, if 9-bit data reception is enabled, the ninth data bit. 9. Get the received 8 Least Significant data bits from the receive buffer by reading the RCREG register. 10. If an overrun occurred, clear the OERR flag by clearing the CREN receiver enable bit.