Spy Hunter to JAMMA Prototype

  1. The MCR board uses a daughter board to obtain readings from potentiometers for both the steering wheel and accelerator. Unlike TRON's spinner, these controls are entirely analog and are read into absolute values using an ADC (analog-to-digital converter). There is one data "bus" sharing inputs into the MCR board for both steering and accelerator, and the value being read is determined by a separate pin on the main board. Depending on what the main board calls for, you must provide the correct value to the pins.

Wrong.

The inputs are mux'ed into a single ADC -- the ADC output data bus isn't shared with anything else (but it could be).
 
Wrong.

The inputs are mux'ed into a single ADC -- the ADC output data bus isn't shared with anything else (but it could be).
The ADC's output is what gets buffered through the LS244. Depending on the value for STREN, either the steering pot or the accelerator are enabled as inputs.

In my converter board, the outputs are multiplexed through an LS157, depending on what the board is asking for.

This is why I put bus in quotes. It's a shared physical pathway... here on analog inputs, or for my adapter a shared digital output.
 
FYI added a short video of gameplay experience to bottom of blog. It's pretty decent. Obviously not the same experience as a steering yoke and pedal. But enjoyable.

I have the next round of PCBs in fabrication for DVTs and will have a few I can send out if anyone would like to build their own for testing. I'll order a bigger batch of the final production boards and probably do what I did with the TRON boards and let the barenaked boards go at cost, or assembled for more to support the research (I usually do EVT, DVT, and PVT runs, @ ~$150/run, so it costs me around $400-$500 just to get to a production board I'm willing to release to the public).
 
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I have the next round of PCBs in fabrication for DVTs and will have a few I can send out if anyone would like to build their own for testing. I'll order a bigger batch of the final production boards and probably do what I did with the TRON boards and let the barenaked boards go at cost, or assembled for more to support the research (I usually do EVT, DVT, and PVT runs, @ ~$150/run, so it costs me around $400-$500 just to get to a production board I'm willing to release to the public).

Research? What is there to "research" when everything you're doing was done a decade ago.

Before tariffs, those boards would have been about $3 each shipped at proto qty. The actual complexity is in in all the cabling you're not including with the bare board.
 
Latest prototype. Working great. I made a few changes and have ordered what I think will be the final boards, black w/ENIG. Fixed a few bugs, added more decoupling, and added a couple of dips to enable CHAMMA support for buttons 5/6, if you want to avoid using an extension connector altogether. I'll ping the thread when I have the final boards ready to go!

IMG_3286.jpeg
 
So would you say this is more for testing boards or you can actually use this to play the game in a jamma type cabinet or supergun set up?
 
I'm enjoying playing it with a gamepad on my setup.

Low/High gear works nicely. The gas pedal button gives you moderate speed in either gear, however if you push "up", you also get the turbo with the exhaust flames. It takes a little getting used to, just as the NES version does, but it works really well for gameplay. See the video at the bottom of the blog.
 
The version in the repo is the board I have in production now, and what I expect will test as the final board. Feel free to run your own batch, although I've ordered some extra in case anyone wants one. It's the same size as this prototype, this is what it looks like fully assembled. Lots of Molex but worth it IMO.

IMG_3291.jpeg
 
Latest board prototypes came in. It turns out I needed to make one tiny connection that will be in the final board revision (already in GitHub). Anyway I'm happy to send out some of these boards as blanks (I'll tell you where to make the small change). All said and done, $10 a blank board plus flat rate priority ($12) seems fair. I have a BOM up as well. So message me if you're interested. This board supports either CHAMMA (via switches at bottom) or an extension harness to get buttons 4-6. The HAS and Axunworks can do both.

IMG_3313.jpeg
 
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