Path: utzoo!utgpu!attcan!uunet!seismo!sundc!pitstop!sun!decwrl!purdue!haven!uvaarpa!virginia!kesmai!dca
From: dca@kesmai.COM (David C. Albrecht)
Newsgroups: comp.sys.amiga
Subject: Re: Joysticks
Message-ID: <198@kesmai.COM>
Date: 4 Nov 88 00:09:50 GMT
References: <941@hub.ucsb.edu> <4@sdcc10.ucsd.EDU>
Organization: Kesmai Corporation, Charlottesville, VA
Lines: 26

In article <4@sdcc10.ucsd.EDU>, cs161agc@sdcc10.ucsd.EDU (John Schultz) writes:
> 
 >   SpaceSpuds (3D) supports Standard IBM Joysticks in the second mouse
 > port.  The RKM suggests approx. 470K ohm pots for analog joysticks,
 > but using pots with this value will yield readings from about 0..49.
 > The range should be from 0..255.  We did some testing and found 1
 > Mega ohm pots will generate the necessary range (approx. 470x2 =
 > 940).  Perhaps Dale or Bob can tell us why this is so...  Anyway,
 > before analog joysticks are to become popular on the Amiga, custom
 > joysticks with 1M pots will have to be produced.  I have a Gravis
 > IBM analog joystick working with SpaceSpuds, but with a range of
 > only -24..+24.  The circuitry in the 500s generate spurious readings
 > with even less range; with 2000s, a more stable range abliet less
 > than a 1000.  Hopefully these problems will be remedied and a major
 > joystick manufacturer will build special joysticks for the Amiga.

I just recently added joystick support to Air Warrior.  As noted, the values
tend to jitter and produce spurious values so I still need to add a dead
band and a low pass filter to make it useful.  I noted that the resolution
of an IBM analog joystick is pretty crappy on the Amiga.  One of the players
came back with that all you had to do was add a .1 uf cap from the pot
wiper to ground.  The value he is currently using is .022.  I haven't
tried this but at some point I no doubt will.  You might try it and see
how it works for you.

David Albrecht