.s
zero	150
one	151
hi	152
temp	153
port	0
.a 	0
.c
:loop	cla
	sta zero
	lda #1
	sta one
	lda #240
	sta hi
	cla
	out port
	com
	out port
	add #1
	out port
	adc zero
	out port
	xor #255
	out port
	ora one
	out port
	and hi
	out port
	lda #3
	out port
	sta temp
	cla
	out port
	lda temp
	out port
	cla
	jz s0
	com
:s0	out port
	lda #1
	stc
	jc s1
	cla
:s1	out port
	lda #255
	jn s2
	cla
:s2	out port
	cla
	jmp s3
	com
:s3	out port
	stc
	rol
	out port
	stc
	ror
	jn s4
	lda #1
:s4	out port
	clc
	jc s5
	com
:s5	out port
	id
	out port
	lda #1
	out port
	cla
	out port
	jmp loop
.e

	
	
	