Help with timer0 for 16f877

[crowinu]

16f877 timer0

hi guys,

i am doing a project for my schoolwork (PIC controlled dimmer) and i need to use the timer0. I need some help in using timer0. another thing i am using assembly language not c Neutral, i guess it makes it more diffcult. i need to do something like this, every 1s a small routine is called and is repeatitly done.
10x for any help

crowinu.

 

[happy2005]

timer0 in c for 16f877

Adjust timer0 prescaler 1/16. Clock freq. should be 4 MHz. Timer0 increments one every 16x1us. it takes 4.096 ms for 256 count. Enable the timer0 interrupt. And increment a register (8-bit) in interrupt service routine of timer0. When the register value reaches the 244 (passed time is approximately 0,999424 sec), clear the register and set a flag.
In the main routine check the flag, if it is true, call the your subroutine.

 

[magnoedu]

dear friend y same the problem please is possible you put the code in c ccs to show how make???

 

[powerelectronics]

hi friend i attach the led code using timer0 .i am used hitech c compiler

#include<pic.h>
/*---------------------------*/

void TMR0Init();

/*---------------------------*/

#define TMR0_TICK 250
#define TMR0_PRESCALE 3 //(FOSC=16MHz,Prescale=3),(FOSC=4MHz,Prescale=1)

#define TMR0_RELOAD (255 - (TMR0_TICK-6))
#define LED RD0

/*---------------------------*/

static unsigned int count;

/*---------------------------*/



//void main(){}

/*---------------------------*/

void TMR0Init(){
TMR0 = 0; // Clear TMR0
INTCON = 0; // Disable all interrupts and clear T0IF
OPTION &= 0xC0; // Turn off least 6 bits to configure tmr0
OPTION |= TMR0_PRESCALE; // set prescaler to 1:x
T0IE = 1; // Enable TMR0 interrupt
GIE = 1; // Enable the global interrupt
}
/*---------------------------*/

void interrupt
tmr0_isr(void){

if(TMR0IF){
TMR0 = TMR0_RELOAD;

count++;
if(count == 1000){
LED = !LED; //Toggles LED once per second
count = 0;
}

T0IF = 0;
}
}
/*---------------------------*/