Path: utzoo!attcan!uunet!mcvax!kth!draken!umecs!apollon!dvlsan
From: dvlsan@apollon.cs.umu.se
Newsgroups: comp.sys.atari.st
Subject: Re: cartridge port addressing
Message-ID: <864@umecs.cs.umu.se>
Date: 24 May 89 12:11:49 GMT
References: <419@carroll1.UUCP> <116@sdcc10.ucsd.EDU>
Sender: news@umecs.cs.umu.se
Reply-To: dvlsan@zeus.cs.umu.se (Stefan Andersson)
Organization: Dep. of Inform.Proc.,University of Umea,Sweden
Lines: 23

In article <116@sdcc10.ucsd.EDU> cs163afu@sdcc10.ucsd.edu.UUCP 
(Some call me...Tim) writes:
>...
>One alternative that works for simple expansions (home grown ones
>come to mind, but a multi-joystick expansion uses this path) is
>through the parallel port.  For some reason, it's bi-directional--
>you could communicate with a device plugged in there.  
>...
Gee... I wanna know how to do this, could you please post info about it(
or e-mail, if that feels better).  (I guess it involves low level programming
of whatever chip drives the centronics interface, but there's no need to
reinvent the wheel :-))

Some time ago i saw an article in byte about writing to the ST cartridge port.
It involved using special hardware (fairly simple, as I recall it) to 
multiplex data and adress out on the adress bus, thereby performing a "write".
If there is sufficient interest, I could dig it out of my bookshelf,
and post a summary.

/Stefan
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