720 joystick -- hackable?

[kspiff]

I think one of the hardest games to get the feel right on is going to be Atari's 720.. I was thinking about picking up a joystick and seeing what it would take to hack, but what kind of joys are these?  Are they the hybrid optical/microswitch-type (or whatever) like Happ's Ult360s?  A pots-based analog joystick (I seem to remember the rotation was clean and had no clicking)?  It probably uses optics (since I'm always seeing replacement optic units for these joys).. I don't think it would be Hall Effect/49-way.. but I dunno.  

Any help welcome.  Thanx!

k-spiff

[kspiff]

It's an optical.. looks like a hack with an OptiPac would be cake, might even not require a new optic board.

k-spiff

[Lindner24]

On a 720 control, there is two optical wheels.
One is normal and the other has only two holes.
I think that is for calibration (so your joystick points
the way your skater is going). So I think it might be
tough to get it dialed in.

[u_rebelscum]

I think one of the hardest games to get the feel right on is going to be Atari's 720.. I was thinking about picking up a joystick and seeing what it would take to hack, but what kind of joys are these?

I'm very interested in this too.

Like you say, it's two optical sensors which can be easily hacked into a mouse's X and Y axes.  Mame currently only uses the X axis for 720, and the second input (the one with two holes) is ignored, AFAIK.  So this means edits to mame source, & probably a 720 real joystick specific build for calibration reasons.

BTW, there's a 720 control on ebay right now.  Let me know if you are bidding on it so I don't over bid you (just in case I cave in and decide I can buy it).

And Lindner24, is that your controller?  Do you know how many holes the normal wheel has?

[Lindner24]

There are 72 holes on a 720 encoder wheel.
That should be easy enough to remember :)

Actually that is my controller. A friend of mine is storing his REAL 720 in my basement, I bought a control panel on eBay for a replacement. The problem is calibration... I can't get the joystick to point the direction the skater is going. It seems to be about 90+ degrees off. I've put it in calibration mode, and it doesn't seem to making it through the whole process.

When he first brought it over the skater didn't spin at all. So I'm still in the trouble shooting stages with no luck yet. It's almost playable but very frustrating.

I think this is a common problem for 720's and it doesn't seem like anybody has  good answer how to fix the problem.

[Jakobud]

it's really nothing special.  Its just a big spinner with a joystick attached.  Totally doable.  Go for it!

Jakobud

[kspiff]

That's why I asked -- I saw the 720 stick on ebay.. but $85 is too rich for my blood.. besides, if it includes the PCB and sound amp it's better to let someone have the stuff that can use it.

So that's how it keeps the skater calibrated.. hm.. well, I can't hack the MAME source anyways so.. I kind of figured it was just calibrated once but somehow knew there had to be something else.. optics mess up sometimes..

Too bad, though, I think that's the first time I've even seen one for sale.. Oscar should do a repro (sic) ..

k-spiff