* = $1000

screen = $400
		lda	#$00
		sta	counter

		lda	#<screen
		sta	modify+1
		lda	#>screen
		sta	modify+2

loop		ldx	#$00

		lda 	#$01
modify		sta	screen,x
		inx
		cpx	#250
		bne	modify

		inc	counter

		clc
		lda	#250
		adc	modify+1
		sta	modify+1
		lda	#00
		adc	modify+2
		sta	modify+2

		lda	counter
		cmp	#4
		bne	loop
		rts



counter		byte	0