Sample program using the WAI instruction for low power mode with the 68HC11

#include <hc11.h>
#include "pia.h"

#define TRUE 1

void tof_isr(void);

unsigned char upcount;

main()
{
	upcount = 0;

	PIA_CRB = 0x00;
	PIA_DDRB = 0xff;
	PIA_CRB = 0x04;
	PIA_B = upcount;

	TOF_JMP = JMP_OP_CODE;
	TOF_VEC = tof_isr;
	TMSK2 |= 0x80;
	TFLG2 = 0x80;

	enable();

	while (TRUE)
	{
		asm(" wai");
	}
}

#pragma interrupt_handler tof_isr

void tof_isr(void)
{
	PIA_B = upcount++;
	TFLG2 = 0x80;
}