Noob question about joystick wiring

[jptsetme]

I've wanted to build a MAME arcade machine for years, and my 5 year old son has recently become very interested in classic arcade games.  I started looking for a cabinet and decided (perhaps impulsively) to buy a broken NFL Blitz 2000 Gold machine.  No board, no monitor, but the cabinet is in decent condition and I'm told the joysticks and buttons all work.

Now that I've done some more research, I see that this game uses 49 way optical joysticks, and it doesn't appear that there's a readily available way to connect these joysticks to a PC.  The GP-Wiz49 controllers seem to have been unavailable for quite a while, and honestly I wouldn't be too eager to spend $140 on 4 controllers for these joysticks anyway.  I don't really need these to be 49 way joysticks and I'm trying to figure out if there's a reason I couldn't wire them up as 8 way (or even 4 way) joysticks to a single I-PAC4 controller.  I'm a software guy and haven't touched a breadboard since college many years ago -- can someone please help me understand if my thinking is flawed (either because it simply doesn't work that way or because it would not function well for some reason)? 

I'm thinking I could demultiplex the joystick output and simply OR together the groups of directions that should map to the 8 (or 4) discrete directions I want to support, and then send that output to the input on an I-PAC. The wiring diagram for the joysticks is on page 95 of the manual here: http://www.crazykong.com/manuals/NFLBlitz2KGold.man.pdf

I'm hoping for advice like "yeah, you can convert these to 8-way or 4-way joystick outputs - that's been done before here's a link to some info", "yeah, you could do that (and maybe a bit of here's how I suggest you do it: DIY with a breadboard, Arduino, something else)", or "you're a moron, that won't work and here's why".  Feel free to add the "you're a moron" part regardless.  :-)

Thanks for your help -- really looking forward to this project.

[RetroACTIVE]

Unfortunately there is no quick and dirty solution to your quest.  49 ways are pretty unique and there really isn't a practical way to 'convert' them.  IMHO, you'd be better off selling them and buying new sticks.

[Damian]

I'm also a newbie and have no direct experience with 49-way sticks. However, I've done a bit of electronic tinkering in my time, and the manual does _seem_ to bear out what jpsetme said. I'd say the easiest thing is to rig them up to power and use a multimeter to verify what the manual seems to be telling you. If there really are a few wires that go high when you want them to, I don't really see why it couldn't work. RetroACTIVE, is there some electrical weirdness with these sticks? I mean, it looks like it's a simple +5V circuit, but I only know enough to get myself into trouble. 

[RetroACTIVE]

I'm also a newbie and have no direct experience with 49-way sticks. However, I've done a bit of electronic tinkering in my time, and the manual does _seem_ to bear out what jpsetme said. I'd say the easiest thing is to rig them up to power and use a multimeter to verify what the manual seems to be telling you. If there really are a few wires that go high when you want them to, I don't really see why it couldn't work. RetroACTIVE, is there some electrical weirdness with these sticks? I mean, it looks like it's a simple +5V circuit, but I only know enough to get myself into trouble. 

No weirdness... just think if it as a 7x7 switch matrix.

This might be what you guys are looking for: 49 Way Joystick Translation

[DeLuSioNal29]

IMHO, you'd be better off selling them and buying new sticks.

+1.  You'd get a pretty penny for those and with that money you can purchase 8-way joys and a joystick encoder.

D

[jptsetme]

Thanks for all the info, guys.  If I could make more for the 49 way sticks than it would cost for new sticks and a controller, that's compelling.  If I were to buy new sticks, are the $8.50 Happ Competition sticks decent?  If I can get decent sticks for what I'd sell these for, it would probably save me a little time and might be better performing / longer lasting.  Any suggestion on where to find buyers?

Thanks for the translation link, RetroACTIVE (and thanks for looking at the manual with me Damian).  Cool to see this has been done, and I think I could do this with less components than they used since I probably don't need to support all the different mappings they have programmed.  Looking at the position table beneath the wiring diagram for the 49 way stick, it looks even easier than I thought  to convert the output to 4 way output.  Splitting the output into 2 4-bit 2's complement nibbles, the high order nibble is up/down (0 center, + up, - down) and the low order nibble is left/right (0 center, + left, - right) -- anyone see a reason why that wouldn't work?

I'm embarrassed to admit that I drew a little logic diagram of how to do this.  1 4-way or gate, 2 2-way and gates and a not (per joystick), and that's probably not optimal.  But if the sticks are worth something as-is, that would probably be the better bet.

Thanks again!
--Joe

[jptsetme]

Here's what I drew for left/right -- same for up/down but with pins 6-9.  This is untested and I probably won't go this route if the sticks have more value as 49 way sticks.  Still interesting.

[RetroACTIVE]

To me there are sooo many 8 way sticks out there that will have far better performance than an 'adapted' 49 way it's just not worth the effort.   But... if you like to tinker and such then certainly have a go at it.  I can see where it's sort of a fun project.

However, if all you have is the 4 sticks and buttons, you have a good deal of 'stuff' to acquire to get to a working machine.  Just consider the amount of time and cash and personal energy you have to invest in it and choose accordingly.

It's all fun no matter how you cut it

[jptsetme]

+1.  You'd get a pretty penny for those and with that money you can purchase 8-way joys and a joystick encoder.

Where would you suggest I sell them?  I might go that route.

[PL1]

+1.  You'd get a pretty penny for those and with that money you can purchase 8-way joys and a joystick encoder.

Where would you suggest I sell them?  I might go that route.

The B/S/T forum is one place to list them.

Since MAME doesn't support them IIRC, you might have better luck putting them up on KLOV since their user base is more focused on dedicated cabs.

This guy has some listed there for $20 each.


Scott