//ZERO CROSSING DETECTOR
unsigned char FlagReg;
sbit ZC at FlagReg.B0;
void interrupt()
{
if (INTCON.INTF){ //INTF flag raised, so external interrupt occurred
ZC = 1;
INTCON.INTF = 0;
}
}
void main() {
PORTB = 0;
TRISB = 0x01; //RB0 input for interrupt
PORTD = 0;
TRISD = 0; //PORTD all output
OPTION_REG.INTEDG = 0; //interrupt on falling edge
INTCON.INTF = 0; //clear interrupt flag
INTCON.INTE = 1; //enable external interrupt
INTCON.GIE = 1; //enable global interrupt
while (1){
if (ZC){ //zero crossing occurred
PORTD.f0 = 1; //Send a 1ms pulse
delay_ms(1);
PORTD.f0 = 0;
ZC = 0;
}
}
}