crystal oscillator required for serial communication for PIC16F877A

[Umair Ahmed]

Hi, i am working with PIC16F877A i need to do the serial communication. kindly guide me what value of external crystal i should use for serial communication. And which is the register used for serial communication in PIC16F877A.

 

[bigdogguru]

The PIC16F877A datasheet contains all the information you need:

PIC16F87XA Data Sheet

Reference: pg 114, TABLE 10-3: BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 0) and TABLE 10-4: BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 1)

FOSC is the crystal frequency, the tables indicated %ERROR, therefore choose your FOSC at a chosen BAUD rate to minimize %ERROR.

The info should get you started in the right direction.