Dreamcast controller to arcade stick help

[aoiddr]

I have kind of hit a brick wall with trying to wire up arcade joysticks/buttons to third party Dreamcast controllers so I can keep VMU support.

I first tried an Interact Quantum Fighter Controller and this works great for everything but the shoulder buttons (L/R). It has horizontal pots and ground/signal/vcc wires and I can't seem to find a clean way to get inputs from them. Tried resistors and diodes and tapping from different pads, but no luck.
(Note: the C and Z buttons are programmable for everything but the L and R buttons...so they're useless.)

I then tried a Madcatz Dreampad, but ended up with one of the controller PCBs that uses three different sets of grounds (instead of one common ground), so only clusters of buttons will work correctly when triggered. Pushing any other buttons gives random button presses or actions (like down might trigger start or something else might turn on that program light on the controller).
Start/A/B/C are wired to one ground on the pcb. X / Y / Z are wired to another. And Up/Down/Left/Right are wired to another.

Anyone thoughts/suggestions here to either fix the above controllers I started or a recommendation for a controller that would definitely work to mod?

 

[kowal]

I think the best solution would be to hunt down some “dead” Dreamcast arcade stick with a working PCB on Buyee. I’ve got three Agetec/ASCII Green Goblin PCBs from back when I used to mod them in bulk, but shipping from Poland to the US wouldn’t be worth it now. Shame you’re not in the EU.

Right now the Goblin has weird prices (eBay) — I used to buy them for like $10–15 just for the shell, and now they’re treated like some kind of retro “legend,” even though the stock setup is complete crap. But I think you can still find one for under $20 — I’d look for something in poor condition but cheap (yellowed case, rust on the panel, snapped cable). Nobody really wants those, so the price stays low, and the PCB is probably still fine

From my experience: out of around 50 different DC sticks, I never had a PCB failure, so they seem pretty bulletproof.

 

[N10248]

I think the best solution would be to hunt down some “dead” Dreamcast arcade stick with a working PCB on Buyee. I’ve got three Agetec/ASCII Green Goblin PCBs from back when I used to mod them in bulk, but shipping from Poland to the US wouldn’t be worth it now. Shame you’re not in the EU.

Right now the Goblin has weird prices (eBay) — I used to buy them for like $10–15 just for the shell, and now they’re treated like some kind of retro “legend,” even though the stock setup is complete crap. But I think you can still find one for under $20 — I’d look for something in poor condition but cheap (yellowed case, rust on the panel, snapped cable). Nobody really wants those, so the price stays low, and the PCB is probably still fine

From my experience: out of around 50 different DC sticks, I never had a PCB failure, so they seem pretty bulletproof.

This is what I did with my NNC cabinet...

 

[Segafan1985]

This is what I did with my NNC cabinet...

This looks super cool.

I still need some type of VMU support for my NNC with Dreamcast setup. Do you have a writeup on how you did this on another thread? I use an Arthrimus so I can have a Naomi and Dreamcast in there at the same time. Would your setup work with that?

 

[N10248]

This looks super cool.

I still need some type of VMU support for my NNC with Dreamcast setup. Do you have a writeup on how you did this on another thread? I use an Arthrimus so I can have a Naomi and Dreamcast in there at the same time. Would your setup work with that?

The VMU is simply connected to the original joystick's PCB, easiest way would be just leave a regular controller inside the cabinet connected to port 3 or 4 of the dreamcast with a vmu plugged in to it.