out	40	speaker_zero
	out	42	speaker_char
	out	40	speaker_one
speaker_wait	in	41	speaker_input
	bne	speaker_wait	speaker_input	speaker_one
	out	40	speaker_zero

speaker_valid	.data	40
speaker_ack	.data	41
speaker_sample	.data	42
speaker_zero	.data	0
speaker_one	.data	1
speaker_input	.data	0
speaker_char	.data	0