typedef void (*voidFunc)(void);
#define RTICTL *((unsigned char*)(0x34 + 0x7))
#define CRGINT *((unsigned char*)(0x34 + 0x4))
#define CRGFLG *((unsigned char*)(0x34 + 0x3))

void initCRG(void (*fp)(void))
{
	// sätt avbrottsintervall
	RTICTL = 0x40;
	
	// aktiver crg
	CRGINT |= 1<<7; // 0x80
	
	// init avbrottsvektor
	*((voidFunc *)0x3ff0) = fp;
}

void kvitteraCRG(void)
{
	CRGFLG |= 0x80;
}