Re: which encoder wheel?

>One thing I've forgotten to ask in all of this is WHICH
>encoder wheel would be used for the input device? I would
>guess the Tempest wheel is the most common and, like
>the Sega wheel, it has a nice heavy flywheel attached.
>
>I have seen (and picked up) some HP encoder assemblies
>that are the size of a panel pot and have quadrature
>outputs. These don't have flywheels, but would be handy
>for a bench setup, or for putting into a little box for
>bench use.

Good point. I haven't counted up all the teeth on the various wheels out
there, but the one I'm using for testing is one of the Clarostat Optical
Encoder assemblies with 128 pulses per revolution. (I think that's
probably quite high compared to Tempest and certainly higher than the Sega
stuff.) It's easy (relatively speaking) to scale the number of pulses
down, but it's a pain to make more "virtual" pulses out of what you get in.
(You need to trigger on rising and falling edges in that case and it's not
something I want to figure out... ;-)

A lot of Atari stuff seems to use a 64 position encoder assembly. Sega
stuff looks clost to that amount as well. Kick was something really
coarse-- maybe 16 or 32 teeth? I don't know about the Atari whirly-gig's
(like Blasteroids) I think they're close to the spinner on Tempest. Major
Havoc I'm not sure about for the "real" controller-- I have a (the?)
prototype Major Havoc roller controller that I can count out I suppose.

IMHO, the Tempest spinner is the best of the lot...

-Clay

Clayton N. Cowgill Engineering Manager
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Received on Tue Aug 5 13:27:39 1997