#INT_RDA

[GQ]

Would somebody suggest why this code wont work, cuz it aint?
Im printing a character upon a serial interrupt

Code:
********************************

#include <16F877a.h>
#device *=16
#include<stdlib.h>
#fuses XT,NOWDT,NOLVP
#use delay (clock=4000000)
#use rs232(baud=4800,xmit=PIN_A1,rcv=PIN_B1,parity=N)

char ch;
int i;

#INT_RDA
void serial_isr()
{
putc('a');
}


void main()
{
enable_interrupts(INT_RDA);
enable_interrupts(GLOBAL);

while(1)
{
delay_ms(333);
}
}

[PCM programmer]

#int_rda only works with the hardware UART.
If you move your RS-232 to pins C6 and C7, then you can use it.
Example:
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, ERRORS)

[GQ]

Thanx,programs working. but it continously prints 'a' once a key is pressed. That means the key acts as just another key triggering the isr. Since it keeps on printing 'a' without getting out of the isr(no delay of while loop), it also means the isr interrupt flag bit is not going low. Am i right?

*****************
Code:

#include <16F877a.h>
#device *=16
#include<stdlib.h>
#fuses XT,NOWDT,NOLVP
#use delay (clock=4000000)
//#use rs232(baud=4800,xmit=PIN_A1,rcv=PIN_B1,parity=N)
#use rs232(baud=4800, xmit=PIN_C6, rcv=PIN_C7, ERRORS)
char ch;
int i;

#INT_RDA
void serial_isr()
{
/*
ch=getc();
if(ch=='A')
putc('a');
else if(ch=='B')
putc('b');
else
putc('E');
*/

putc('a');
}


void main()
{
enable_interrupts(INT_RDA);
enable_interrupts(GLOBAL);

while(1)
{
delay_ms(1000);
}
}

[PCM programmer]

You must actually 'get' the character while inside the isr. Do this with
the getc() function. You have it commented out.

[GQ]

thanx