Sega Hot Rod Wheel - Connecting Optics?

[Silver]

I've picked up a Sega Hot Rod steering wheel in great condition, it still has the optics and everything all working.

I want to hook this up probably by an opti-pac, and was wondering if I can use the current optic set up? Anyone used one of these before?

Or will I have to remove the optics to use a mouse hack?

Heres a couple of pics:

EDIT: If it would help to see the otherside of the PCB I can get a pic of that. As you can see there its relatively simple, but does have Caps and resistors... I was hoping I may be able to directly solder from the sensor outputs to optipac. The optic wheel looks unusual to me in that the gaps/solids are so big (the big black cap bit)....

[Minwah]

I expect you could just hook it up to an OptiPac or mouse hack using the termnals already there - looks like there are 6 which makes sense: 5v, GND, X1, X2, Y1 & Y2 - you just need to figure out which is which

That optic wheel is wierd - looks like it only has a few protrusions, rather than the normal toothed wheel.

Edit: ignore what I said, of course it only has 1 axis.  Should still be possible to hook it up, but I'm not sure what the extra contacts are for.

[JB]

I can't see the encoder wheel.

Unless I'm missing something, it looks like the steering wheel axle is attached to a simple gear that drives a mechanism in the small "black box" next to it.

[Silver]

@JB: It's just unusual - try this attached pic

@Minwah yes I hope you're right. Is it usual to have 2 LED's on an optic board? May be thats where the extra connections come from....

[Minwah]

@Minwah yes I hope you're right. Is it usual to have 2 LED's on an optic board? May be thats where the extra connections come from....

I don't honestly know, I think some do, but they are usually self contained in a black housing so are not visible.  My only concern is how the wheel will perform when interfaced, with that unusual optic wheel - worth a try though.

Hopefully if Oscar sees this thread he might be able to shed some more light...

[Silver]

Hmmm yes I'm a bit stumped by the 6 connectors on the pcb.... a lot of arcade wheels (eg atari) seem to have just the 4 - x1,x2,+ve,ground.... but then I do seem to have an extra LED+sensor.

Suggestions for testing welcome - although I don't have a scope or anything to check out changing voltages...?

[OSCAR]

I imagine that optic board would just fine with an Opti-PAC, or probably with a mouse hack.   The encoder wheel is a different design than most, but basically works the same.  Like Arkanoid, it uses a gear set so the wheel turns "X" amount of times per revolution of the wheel.  So if the wheel were to make one revolution, the encoder wheel may make 10, 12, 20... amount of revolutions, effectively making it much like a wheel with 60+ teeth.

The IC is likely a buffer chip, in the event the wheel is stopped with the wheel partially blocking the optics.  It's not too unusual to see optic boards with more than the "typical" Atari style 4-pin connections.  Midway, for example, used a 10-pin connector on the optic board for Tron.

Sorry I can't give you any specific information on that particular optic board, I haven't had the opportunity to play with one of those before.  If you could locate a manual for Hot Rod, or if there is another Sega game of the same vintage that used an optical control, the manual may tell you what each pin is supposed to do.  If you look at the traces on the board, you may just check to see if some of the pins go to the same point on the board.  On the older games, it wasn't unusual to have more than one GND or +5V connection on a board, just in the event of a wire harness failure.  Good luck!

[Silver]

OSCAR - thats very promising thanks!

I've been hunting down a manual for a pinout to no avail. Its good to know there are other boards with similar number of outputs etc...etc...

I'm trying to trackdown the IC pinout too, to give me the +ve and ground lines, as well as the voltage (or does everything use +5v in the arcade/jamma world?)

Thanks.

PS your spinners are working a treat!

[Silver]

Ok, the IC is a bunch of Schmitt triggers by the looks of things - so just taking the TTL (0-5v input signals) and cleaning them up into sharp transistions with different +ve -ve thresholds, so looks like that won't be a problem at all (In fact probably helps to keep it in use).

Its also given me the 0V and +5V on the PCB.

It does look like there are 4 outputs though (coming from the outputs of the schmidt triggers) rather than extra power lines.

How would I go about wiring these to a 2 input optipac or mouse hack?

[Silver]

Ok, apologies for gettin' all electro-techie. Basically I've found there is an x1 and x2 output (1 for each light sensor) - each have which have gone though a schmitt trigger on the IC -  and then another 2 outputs, say x1b and x2b which are x1 and x2 eached passed through ANOTHER schmitt trigger on the IC....

anyone shed any light on what this achieves?

EDIT: Woopsi - think I've just remembered - I believe schmitt triggers invert the logic as well as the hysteresis effect (different threshold levels). So another pass inverts them again - presumable back to active high/low whichever they started with. So this actually gives me a wheel with both active high and low outputs. Or am I WAY out of the ball park here?

Apologies for answering my own posts... First sign of madness?  (Oh no wait that would be deciding to build some huge arcade cab in my flat.....  )

[JB]

@JB: It's just unusual - try this attached pic

Ah, I see now...
The second LED may be an attempt to get a reasonable resolution out of what seems to be a VERY low res encoder "wheel". Since one light is blocked/unblocked before the second one, it's SORT OF like having more teeth.

Or that would be why it's geared to start with. Duh.
...
Combine the 2 for even more accuracy?

[pcates]

That wheel (with the exception of the encoder wheel) looks just like the ones I have from super off road. The optics look the same it has 6 connectors, but only uses 4. I do not remember exactly which ones are used, but the manual for super off road is on KLOV. I just hooked up the 5v gnd X1 and X2 to the optipac and it works perfectly. I do not know what to make of that encoder though.... If the resolution is too low, I have an extra one that would fit that exactly, and has the normal amount of teeth.
Good Luck, Patrick

[NoOne=NBA=]

Here's a picture of one of my Off-Road Wheels, with an Oscar Optic Board held in place on the original bracket by foam tape.
Add an Oscar USB Mouse Hack, and you are set as far as the wheel connections go.

Mine works flawlessly with that setup.
I'm not sure how they will work with your existing encoder wheel though due to the tooth size.

[Silver]

...but the manual for super off road is on KLOV. I just hooked up the 5v gnd X1 and X2 to the optipac and it works perfectly.

I do not know what to make of that encoder though.... If the resolution is too low, I have an extra one that would fit that exactly, and has the normal amount of teeth.

I love this board! Thanks for that - exactly what I needed.  That manual tells me which 2 ouputs are used for off-road - so I'll try those.

Although it is low res it obviously worked fine in the arcade, and thats what I'm trying to copy. Anyway if its too low, I may well take you up on the offer of an extra one! Thaks pcates!

@NoOne=NBA=

Fantastic - if it does not work with the current setup, I'll be placing an order with  Oscar....