jhs@MITRE-BEDFORD.ARPA (02/22/88)
> So how many joystick ports are there? My 800/Fossil has four. Is there > only one on an XL? There are two joystick ports on the XL/XE series machines. I guess I was thinking that both would be used to provide an 8-bit-wide parallel port such as the fellow referred to, since each has just 4 parallel bits. You could, of course, use just one joystick port to get a 4-bit parallel path, leaving the other port free for a normal joystick. I believe the individual pins can be programmed for input or output separately, so you could even set it up with two 1-bit inputs and 2 1-bit outputs. Hmm... this would let you implement two separate bidirectional serial ports. In turn this would let you set up a RING of serial ports with as many Ataris around the ring as you wished. Or you could set up two independent unidirectional rings. I can see there are a lot of communication possibilities I never even thought of, using the joystick ports. However, if you want to do an 8-bit parallel connection there, it would tie up both ports as I indicated previously. -John Sangster, jhs@mitre-bedford.arpa