pic16f877a uart not working

[navin tiwari]

hello there!
I’m trying to communicate with PC using pic16f877a’s uart.. I’ve written a code in HITECH C.. but it doesn’t seem to work.. pls help.. I’m using 20 MHz crystal and 9600 bauds..
the code is given below..

<code>
#include <htc.h>
#define _XTAL_FREQ 20000000
__CONFIG(FOSC_HS&LVP_OFF&CP_OFF&BOREN_OFF&PWRTE_OFF&WRT_OFF&WDTE_OFF);
unsigned char x;
void main()
{
    TRISC6 = 1;
    TRISC7 = 1;
    BRGH = 1;
    SYNC = 0;

    SPEN = 1;
    SPBRG = 129; //9600 baud with 20MHz
    TXIE = 1;
    RCIE = 1;
    GIE = 1;
    PEIE = 1;
       CREN = 1;
    TXEN = 1;
    while(1);
    
}

void interrupt ISR(void)
{
    if(RCIE && RCIF)
    {    
        x = RCREG;
        if(TXIF)
            TXREG = x;
            __delay_ms(100);
    }
}
</code>
 

[AJISH ALFRED]

Hi Navin,

I would suggest to simplify the code by avoid the interrupt. Place that piece of code which writes into the transmit buffer inside the infinite loop of the main code and try again.

[erwin]

check your loop or try to use mikroC it is easier to understand..there is a library for uart…

[Author]

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