Path: utzoo!mnetor!uunet!husc6!uwvax!rutgers!iuvax!bsu-cs!cfchiesa
From: cfchiesa@bsu-cs.UUCP (Sir Xetwnk)
Newsgroups: comp.sys.atari.8bit
Subject: Re: Linking two computers
Message-ID: <2178@bsu-cs.UUCP>
Date: 21 Feb 88 21:05:57 GMT
References: <578NU109703@NDSUVM1>
Organization: CS Dept, Ball St U, Muncie, Indiana
Lines: 29
Summary: Still having a joystick port free...


In reference to Fred Sullivan's query, the 800XL has TWO joystick ports; the
discussion that claims "but then you wouldn't be able to plug in your joy-
stick" assumes (quite natrally) that one wishes to perform 8-bit I/O -- and
it happens that each joystick port accesses FOUR bits.  Therefore you need
TWO joystick ports to transmit ONE 8-bit data byte.

Or do you?

I would give some thought to the possibility of using only ONE joystick
port, and performing 4-bit I/O over the port-to-port line, reassembling the
original bytes after both halves ("nybbles") are received.  This may sound
awful, but remember something else: SERIAL data transmission uses a ONE-bit
data line, and that works just fine!  (You could conceivably use the four-
bit joystick-cord connection to send four simultaneous channels of serial
data, by the way....  It is entirely a matter of how complicated a handler 
you're willing to attempt to write!

Now you've got me wishing I had a second Atari to try all of this out on!

:-)

Chris Chiesa

-- 
<><><><><><><><><><><><><><><><><><><><><><><><><><><><> Chris Chiesa <><><><><>
<> {ihpn4|seismo}!{iuvax|pur-ee}!bsu-cs!cfchiesa                              <>
<> cfchiesa@bsu-cs.UUCP                                                       <>
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