timer0 interrupt setting

main.c

#include <p18f4553.h>
#include "task_led.h"
#include "timer0.h"

//******************************************************************************
//  CONFIG
//******************************************************************************
        #pragma config PLLDIV   = 5         // (20 MHz crystal on PICDEM FS USB board)
        #pragma config CPUDIV   = OSC1_PLL2  
        #pragma config USBDIV   = 2         // Clock source from 96MHz PLL/2
        #pragma config FOSC     = HSPLL_HS
        #pragma config FCMEN    = OFF
        #pragma config IESO     = OFF
        #pragma config PWRT     = OFF
        #pragma config BOR      = ON
        #pragma config BORV     = 3
        #pragma config VREGEN   = ON      //USB Voltage Regulator
        #pragma config WDT      = OFF
        #pragma config WDTPS    = 32768
        #pragma config MCLRE    = ON
        #pragma config LPT1OSC  = OFF
        #pragma config PBADEN   = OFF
//      #pragma config CCP2MX   = ON
        #pragma config STVREN   = ON
        #pragma config LVP      = OFF
//      #pragma config ICPRT    = OFF       // Dedicated In-Circuit Debug/Programming
        #pragma config XINST    = OFF       // Extended Instruction Set
        #pragma config CP0      = OFF
        #pragma config CP1      = OFF
//      #pragma config CP2      = OFF
//      #pragma config CP3      = OFF
        #pragma config CPB      = OFF
//      #pragma config CPD      = OFF
        #pragma config WRT0     = OFF
        #pragma config WRT1     = OFF
//      #pragma config WRT2     = OFF
//      #pragma config WRT3     = OFF
        #pragma config WRTB     = OFF       // Boot Block Write Protection
        #pragma config WRTC     = OFF
//      #pragma config WRTD     = OFF
        #pragma config EBTR0    = OFF
        #pragma config EBTR1    = OFF
//      #pragma config EBTR2    = OFF
//      #pragma config EBTR3    = OFF
        #pragma config EBTRB    = OFF

#define GIEL()		INTCONbits.GIEL=1;

unsigned int counter=0;
unsigned char flag_1sec=0;
unsigned char flag_2sec=0;
unsigned char flag_3sec=0;
unsigned char flag_led1=0;
unsigned char flag_led2=0;

void main()
{
    //------------------------------------------------------------------------------
    //  Init PIC periphery
    //------------------------------------------------------------------------------
	RCONbits.IPEN=1;
	mInitLEDAll();
	Timer0_Init();
	Timer0_Write(63661);
	Timer0_Start();
	INTCONbits.GIEH=1;

	while(1)
	{
		if(flag_led1==1)
		{
			flag_led1=0;
			taskLED1();
			
		}

		if(flag_led2==1)
		{
			flag_led2=0;
			taskLED2();
		}
	}

}

//----------------------------------------------------------------------------
// High priority interrupt vector
void InterruptHandlerHigh() ;
#pragma code InterruptVectorHigh = 0x08
void InterruptVectorHigh(void) {
  _asm
    goto InterruptHandlerHigh //jump to interrupt routine
  _endasm
}

//----------------------------------------------------------------------------
// Low priority interrupt routine
#pragma code
#pragma interrupt InterruptHandlerHigh
//
// Timer0 overflow
void InterruptHandlerHigh() 
{
    if (INTCONbits.TMR0IF) {
		INTCONbits.TMR0IF = 0;

		//set timer int on overflow
   		Timer0_Write(63661);

		counter++;
		if(counter>=100) 
		{
			counter=0;
			flag_1sec=1;
		
		}
		
		if(flag_1sec==1)
		{
			flag_1sec=0;
			flag_2sec++;
			flag_led1=1;
		}

		if(flag_2sec==2)
		{
			flag_2sec=0;
			flag_led2=1;
		}
	}
}

task_led.c

#include "task_led.h"

void taskLED1(void)
{
	mLED_1^=1;

}
	
void taskLED2(void)
{
	mLED_2^=1;
}

task_led.h

#ifndef TASK_LED_H
#define	TASK_LED_H

#include <p18cxxx.h>

#define mInitLED1()		   {TRISBbits.TRISB6=0;}
#define mInitLED2()		   {TRISBbits.TRISB7=0;}
#define mInitLEDAll()	   {mInitLED1(); mInitLED2();}
#define mLED_1              LATBbits.LATB6
#define mLED_2              LATBbits.LATB7

void taskLED1(void);
void taskLED2(void);

#endif	/* TASK_DISPLAY_H */

timer0.c

#include "timer0.h"

void Timer0_Init(void)
{
	TMR0H = 0;                // Reset Timer0 to 0x0000
	TMR0L = 0;
	INTCONbits.TMR0IF = 0;    // Clear Timer0 overflow flag
	INTCONbits.TMR0IE = 0;
	
/* T0CON values
			bit 7 TMR0ON: Timer0 On/Off Control bit 
			1 = Enables Timer0 
			0 = Stops Timer0
			bit 6 T08BIT: Timer0 8-Bit/16-Bit Control bit 
			1 = Timer0 is configured as an 8-bit timer/counter 
			0 = Timer0 is configured as a 16-bit timer/counter 
			bit 5 T0CS: Timer0 Clock Source Select bit 
			1 = Transition on T0CKI pin 
			0 = Internal instruction cycle clock (CLKO) 
			bit 4 T0SE: Timer0 Source Edge Select bit
			1 = Increment on high-to-low transition on T0CKI pin 
			0 = Increment on low-to-high transition on T0CKI pin 
			bit 3 PSA: Timer0 Prescaler Assignment bit 
			1 = TImer0 prescaler is NOT assigned. Timer0 clock input bypasses prescaler. 
			0 = Timer0 prescaler is assigned. Timer0 clock input comes from prescaler output.
			bit 2-0 T0PS2:T0PS0: Timer0 Prescaler Select bits    
			111 = 1:256 Prescale value
			110 = 1:128 Prescale value
			101 = 1:64   Prescale value
			100 = 1:32   Prescale value
			011 = 1:16   Prescale value
			010 = 1:8     Prescale value
			001 = 1:4     Prescale value
			000 = 1:2     Prescale value
*/

//set up timer0 see abive
	T0CONbits.TMR0ON=0;
	T0CONbits.T08BIT=0;
	T0CONbits.T0CS=0;
	T0CONbits.PSA=0;
	T0CONbits.T0PS=5;
	
	INTCON2bits.TMR0IP=1;
}

void Timer0_Start(void)
{
	T0CONbits.TMR0ON = 1;	// Enable Timer0
	INTCONbits.TMR0IE = 1;  // Enable Timer0 overflow interrupt
}

void Timer0_Stop(void)
{
	T0CONbits.TMR0ON = 0;	// Disable Timer0
	INTCONbits.TMR0IE = 0;  // Disable Timer0 overflow interrupts
}

void Timer0_Write(unsigned int timer0)
{
	union Timers timer;

	timer.lt = timer0;    // Copy timer value into union

	TMR0H = timer.bt[1];  // Write high byte to Timer0
	TMR0L = timer.bt[0];  // Write low byte to Timer0
}

timer0.h

#ifndef __TIMER_0_H
#define __TIMER_0_H

#include <p18cxxx.h>

/* used to hold 16-bit timer value */
union Timers
{
  unsigned int lt;
  char bt[2];
};

void Timer0_Init(void);
void Timer0_Start(void);
void Timer0_Stop(void);
void Timer0_Write(unsigned int timer0);

#endif