Timer0 Interrupts. Help!!!

Hi

I am trying to modify the following code so that the LED on PORTD is desplayed every 2second. I cant figure it out for the life in me!! I think about looping the timer
But as far as I can see the timer is opperatring in the background and so how do I loop it? I have a hit that the LED does not have to flash every time the interrupt occures.
But i canot see how to achieve this.

//=========================================================================================
// Preprocessor Directives
//=========================================================================================
#include<io16f877.h>
#pragma vector=0x04



//=========================================================================================
// Global Variables
//=========================================================================================


//=========================================================================================
// ANSI Prototypes
//=========================================================================================
__interrupt void my_ISR(void);
void del(void);

//=========================================================================================
// The Main Program
//=========================================================================================

void main(void)//Main Program Starts Here
{
//Timer0, interrupt, PORTA and PORTB are initialised here


TRISB=0x00;
TRISD=0x00;
OPTION=0x07;
INTCON=0xa0;
TMR0=0x00;
PORTD=0x00;
PORTB=0x00;


while(1)
{
del();
PORTB=PORTB+1;
}


}
//========================================================================================
// User Defined Functions
//========================================================================================

void del(void)
{
unsigned int i;
for (i=0;i<32000;i++);
return;
}

//========================================================================================

__interrupt void my_ISR(void)

{

T0IF=0;
PORTD=PORTD^0x08;
TMR0=0x00;

}



Thanks for any help.

benscott171 said:

I am trying to modify the following code so that the LED on PORTD is desplayed every 2second.

Click to expand...

Is this only one LED? If so there is no need to use the PORTB=PORTB+1; command. Instead you can use:


Question: you said that the LED is in PORTD, but you are driving PORTB. If it is on PORTD, then in the above code replace PORTB with PORTD.
Assuming that you have done proper initializations and your delay function is OK, then it should work.

Hope this helps.

EDIT: With the above code you don't need timer interrupt, remove the code inside interrupt.