HI-TECH PICC18 external interrupt doesn't work

[khaled ragab]

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Code C - [expand]
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#include<htc.h>
#include"lcd_fns_4bit_hitech_roll.h"
#define _XTAL_FREQ 20000000
 
 
#pragma config PBADEN = OFF
#pragma config FOSC = HS
#pragma config BOR = OFF
#pragma config WDT = OFF
 
 
unsigned int count=0;
 
//-----------------------------------------------------------------------------------------------------
//-----------------------------------------------------------------------------------------------------
 
void init_interrupt_ports()
{
 
PEIE=1;
GIE=1;
INT0IE=1;
INT1IE=1;
ei();
TRISB=255;
PORTB=0;
 
TRISC=0;
PORTC=0;
 
}
 
//-----------------------------------------------------------------------------------------------------
//-----------------------------------------------------------------------------------------------------
 
void tmr1_start (unsigned char sampling_freq)
{
//--------------------------------
//note : max sampling time (timer) = 520 ms => min sampling freq = 2
//max sampling time (unsigned char) = 255 => min sampling freq = 4
//--------------------------------
 
unsigned char sampling_time_ms;
unsigned int set_value;
float req_value;
 
T1CON=0b00110001;
 
sampling_time_ms = (1000/sampling_freq);
 
//--------------------------------
//fosc:20mhz ---fosc/4---> 5mhz ---1:8prescaler---> 625khz ==> time of a single colck tick = 1000/750000 = 1.6*(10^-3)msec
//1.3*(10^-3)msec * (2^16-1(no of tmr1 ticks)) = 87ms(timer max capacity) 
//--------------------------------
//to determine what value to set in the timers regs to count a certain time
//max value = 2^16-1 = 65535
//required value = sampling_time_ms/(8*10^-3)
//set_value = max value - required valuue
//--------------------------------
req_value = ((sampling_time_ms*1000) / (1.6));
set_value = (int)(((2^16)-1)- req_value);
 
TMR1L=set_value;
TMR1H=(set_value>>8);
}
 
//-----------------------------------------------------------------------------------------------------
//-----------------------------------------------------------------------------------------------------
 
void interrupt ISR(void)
{
    if(INT0IF==1)
    {
        count++;
        INT0IF=0;
    }
}
 
//-----------------------------------------------------------------------------------------------------
//-----------------------------------------------------------------------------------------------------
 
void main()
{
init_lcd();
init_interrupt_ports();
tmr1_start(20);
while(1)
{
    if(TMR1IF==1)
    {
    TMR1IF=0;
    gotorc(0,0);
    show_number(count);
    tmr1_start(20);
    }
}
}

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this is the code i don't know where is the problem the intif is always zero never goes high

 

[internetuser2k12]

#pragma config PBADEN = OFF
#pragma config FOSC = HS
#pragma config BOR = OFF
#pragma config WDT = OFF

comes in mplab c 18 code. Are you sure it is hitech c code?

I think INT0IE and INT0IF should be written as INCONbits.INT0IE and INCONbits.INT0IF