Path: utzoo!utgpu!watmath!att!dptg!rutgers!apple!usc!ginosko!aplcen!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.sys.apple
Subject: Re: IIGS capability question
Message-ID: <10887@smoke.BRL.MIL>
Date: 31 Aug 89 00:55:59 GMT
References: <470@ncelvax.UUCP> <10836@smoke.BRL.MIL> <2237@netcom.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 23

In article <2237@netcom.UUCP> kreme@netcom.UUCP (Kreme The Immortal) writes:
>In article <10836@smoke.BRL.MIL> gwyn@brl.arpa (Doug Gwyn) writes:
>>If you want to play arcade games, you need a joystick.  This should be
>>Apple's (//e-compatible), because others cheat on the circuitry and may
>Huh? I have used a CH Mach III on my //e and on various GS machines without
>a problem.  I've never had a problem, and I've never hear of CH cheating
>on circutry...  Care to explain?

Apple's joystick uses 150Kohm potentiometers.  This is a somewhat unusual
value, so some manufacturers substitute 100Kohm pots (for example) and
add capacitance to maintain the same RC time constant for the 555 timer
that coverts the resistance to a counter value.  This approach assumes
that all Apples supply the same value of internal capacitance, which may
not be the case.

The other common change is to use higher resistance values to extend the
count range.  That means that center position would not be count 127,
for example.  If the software does not provide a joystick calibration
procedure (some do, e.g. Xenocide), then such a joystick will not work
with that program in the way the user expects.

I got the above information from various sources and don't swear that
it's completely correct..