#define THRESHOLD 10
main()
{
	static int j, d;

#asm
	ld a,0x51
	ioi ld (WDTTR),a
	ld a,0x54
	ioi ld (WDTTR),a
#endasm

#nodebug
	WrPortI(SPCR, &SPCRShadow, 0x84);
	WrPortI(PEFR, &PEFRShadow, 0x00);
	WrPortI(PEDDR, &PEDDRShadow, 0x00);
	BitWrPortI(PADR, &PADRShadow, 1, 1); // Preset the gate output high
	while(1) {
		while(1) {
		/* Bring PA0 low, then high again, leaving PA1 high.  Making this inline assembly reduces the
		time this takes from 15 us to 1 us. */
#asm
			ld a, 0x03
			ioi ld (PADR), a
			ld	(PADRShadow), a
			ld a, 0x02
			ioi ld (PADR), a
			ld	(PADRShadow), a
			nop
			nop
			nop
			nop
			nop
			nop
#endasm
			d = RdPortI(PEDR);
			j = 0; // delay
			if(d > THRESHOLD) {
				break;
			}
		}
		/* If the count goes over the threshold for two consecutive cycles, then trip the gate.
		For speed, the second test is inlined instead of being made into some sort of loop with a
		variable check. */
#asm
			ld a, 0x03
			ioi ld (PADR), a
			ld	(PADRShadow), a
			ld a, 0x02
			ioi ld (PADR), a
			ld	(PADRShadow), a
			nop
			nop
			nop
			nop
			nop
			nop
#endasm
		d = RdPortI(PEDR);
		j = 0; 
		if(d > THRESHOLD) {
			//BitWrPortI(PADR, &PADRShadow, 0, 1); // Set the gate output low
#asm
			xor a, a
			ioi ld (PADR), a
			ld	(PADRShadow), a
#endasm
			
			while(1) { /* check to see if the reset switch has been pressed */
				d = RdPortI(PBDR);
				if(!(d & 0x04)) {
					BitWrPortI(PADR, &PADRShadow, 1, 1);
					break;
				}
			}
		}
	}
}