I’ve been working on and off on the SF2′ board set I got a few weeks ago. I got a great deal on the board, but I knew going in that it was untested and potentially broken. After getting it all set up, it boots fine but has graphical corruption and acts as if Button-4 (light kick for SF2′) is constantly being pressed. Not good! Let’s get to diagnosing the issue.
Some base information needed for the diagnosis:
- NEO 29 Cab w/ standard loom
- CPS1′ board w/ JAMMA connector
Before starting to diagnose the issue, let me point out why the above notes are important: JAMMA boards are not natively compatible with MVS cabinets. The pinouts on each of the standards is just slightly different and because of this you will need a converter. I purchased this one from Jammaboards who seem to make them to order. They also offer the reverse direction of MVS PCB to Jamma Cabinet if you need that instead.
Now, the first thing I did was to check the pinouts on my wiring loom and on the CPS1 Kick Harness to make sure nothing was amiss. After verifying everything was correct there, I disconnected the kick harness just to make sure it wasn’t causing some sort of weird short (because MVS natively supports 4 Buttons, I was only using the kick harness to supply input to Button 5 and Button 6, which means it wouldn’t have been causing my issue with Button 4. I disconnected it just to be safe, though.)
After looking around online and finally soliciting help on ArcadeOtaku, I took the next step of unplugging every single input on my cabinet. My thought was that my wiring loom may have been incorrectly set up by the previous owner and that was what was presenting the Button 4 problem. Even with every input disconnected, the problem remained. Because of this, I ruled out the kick harness.
I’m currently in the process of reseating all of the EPROM chips in hopes that might fix the graphic corruption that is happening on screen. Unfortunately, however, I suspect that the problem resides with the B/C boards themselves because that is what holds the graphic data as well as the Button 4 input data. I’ll make another post when I make more progress on this.