Xref: utzoo comp.sys.amiga:71488 comp.sys.amiga.hardware:4509
Path: utzoo!attcan!uunet!cbmvax!raible
From: raible@cbmvax.commodore.com (Bob Raible - LSI Design)
Newsgroups: comp.sys.amiga,comp.sys.amiga.hardware
Subject: Re: Trackball
Message-ID: <15812@cbmvax.commodore.com>
Date: 12 Nov 90 20:34:25 GMT
References: <10896@milton.u.washington.edu>
Reply-To: raible@cbmvax.commodore.com (Bob Raible - LSI Design)
Organization: Commodore, West Chester, PA
Lines: 19


	Let me preface this message by stating that instructions have
posted many times on how to hack an Atari Trakball, hopefully some kind
soul will email(I will if I can dig it up). Now for the bad news - I 
also obtained an Atari Trakball for $4 or so while on vacation and when
I excitedly disassmebled mine and found to my chagrin that the posted
instructions must have been referring to a different model. If this is
the case email me and I'll try to re-create my steps. It turns out that
Atari has a lot of logic inside to convert mouse(trakball) type
quadrature signals into either joystick position info or some other
weird encoded form, depending on the posiion of the switch on the back
panel labelled JS/TB. The unit black and quite massive with a ball
almost the size of a billiards ball. The only markings other than ATARI
TRAK-BALL is "KM-483   8" on a paper label stuck on the underside.  The
two fire buttons are wired together, but I was easily able to bring both
out with a cut and jumper.

As a note of encouragement, I note that shoot'em ups such as Hybris and
Battle Squadron greatly benefit from this nifty appliance!