zadatak2 Lo2

//L02 zadatak 2

.equ delayCnt = 4 // ovo racunamo sa onom formulom za X
.def tmp = r16
.def mask = r17
.cseg
	rjmp reset

reset:
	ldi tmp,high(RAMEND)
	out	SPH, tmp
	ldi	tmp, low(RAMEND)
	out SPL, tmp

	ldi tmp, (1<<0)
	out DDRA, tmp

	ldi mask, (1<<0)


	main:
		in tmp, PORTA //ucita podatak s porta
		eor tmp, mask  //XOR-a s maskom koju smo ucitali
		out PORTA, tmp

		rcall delay
	rjmp main

	delay:
		push r17
		push r18
		push r19

		clr r17
		clr r18
		ldi r19, delayCnt

		delay_loop:
			dec r17 ; 0,255 , 254... , 0
			brne delay_loop
				dec r18 ; 0,255,254,...,0
				brne delay_loop
					dec r19 ; n,n-1
					brne delay_loop
		pop r19
		pop r18
		pop r17

ret