ISR:
	push tempreg
	lds tempreg,CPU_SREG
	push tempreg

	; counterreg will be only incremented 
	; when counterreg is below 16
	ldi tempreg,0x0F
	cpse tempreg,counterreg
	inc counterreg

	pop tempreg
	sts CPU_SREG,tempreg
	pop tempreg

	reti