USART Receiving in MPLAB (PIC16F877A)

[rohan0630056]

pic16f877a usart tutorial

I am trying to receive a number send from PC to the PIC16F877A. I learned to program on MPLAB... I can transmit data from PC to PIC but cant receive,, can any1 PLZ help me on this purpose. PLZ Help me...i cant find y the code is not working...can u plz tell me...

My code is given below:

list p=16f877
include <p16f877.inc>

org 0x00
goto start

start
bsf INTCON, GIE
bsf INTCON, PEIE
call initialPORTS
call initialSPAC
return

initialPORTS
bsf STATUS, RP0
movlw b'00000000'
movwf TRISB
movlw b'11000000'
movwf TRISC
bcf STATUS, RP0
clrf PORTB
clrf PORTC
return

initialSPAC
bsf STATUS, RP0
movlw b'00100100'
movwf TXSTA
movlw .25
movwf SPBRG
bcf STATUS, RP0
movlw b'10010000'
movwf RCSTA

loop
btfsc PIR1, 3
call initialREC
goto loop
return

initialREC
movf RCREG,0
movwf PORTB
return

end

 

[wp100]

mplab pic16f877 usart

Hi,

This tutorial should help http://www.winpicprog.co.uk/pic_tutorial7.htm
See example 7.7 for the hardware version - it does work.

 

[rohan0630056]

pic16f877 usart example

Thx a lot....bt can u tell me the mistake i made..in my code...

 

[wp100]

mplab pic16f877a

Hi,


WHAT !!! I give you that good code example and you still want me to debug your code !!

Well you will have to call my premium rate help line at 500 TAKA per minute for the answer ! :wink:


You do not show your oscillator fequency, so cannot be 100% sure those Init settings are right.

However, if you compare your code with the example I showed, you will spot what I think is the only line of code in error.

Its a double fault, first you are checking the wrong bit and second you are doing the wrong test on it.
(the btfss/sc is an error I often used to make)

btfss PIR1, RCIF ;check for received data


Don't know what programmer you are using, but some of them like the Pickits do have an inbuilt Debugger and Usart tools that can be very helpfull.