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piscian18

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I have a Square Multi Design G-balance with a multi Jamma/JVS setup however it's missing the conversion I/O listed in the manual.

The main cabin has JVS and Jamma Plugs per the manual, however my cab is basically missing all of it. It only has this little conversion board and thats the catch. It looks like its not JVS to the control panel. Its proprietary.

Does anyone recognize the JVS board and that Jamma cable and know how I could get either? If I did want to to tear it out but retain the jamma and JVS plugs any recommendations on the best course of action?

How its supposed to look

6x9M0Av.jpg


the JVS i/o board
0HcZHwD.jpg


What I'm stuck with
8ov4qDy.jpg



Board to control panel

b7KQ2Qo.jpg
 
I have a G-Balance that has it's own problems (my original I/O fried), but I can answer some of your questions.

First off, the little converter i/o you have seems to be just that - a pin converter. Probably it is changing the G-Balance pins to conform to whatever JVS I/O was in the cabinet previously. I think the original loom in the G-Balance is standard JVS, as mine used to work flawlessly with both a Naomi and a Type X2, with the original GFI I/O and no converter. So, possibly your cabinet's previous owner had something like a Taito Fast i/o in there, which has different pin settings.

The reason that that is likely is that Taito I/Os are somewhat easier to use as a replacement if the original GFI I/O breaks, since the G-Balance outputs 12v to the JVS only, using the same connector as the SEGA JVS 5v... which totally fries a SEGA JVS if you carelessly hook it up, (something I discovered recently to my chagrin). With that converter, you'd be able to slot in a Taito fast I/O and go, since they also like 12v (if it is in fact built for Taito Fast I/O pins).

What you will not get with that is the slot for the jamma connector (the black thingie in your pic), which goes into the original GFI I/O. There IS an analogue connector on many I/Os, but you'd probably have to trial and error your way into finding the right pin-outs, since they're not meant for jamma. Since you're ALSO missing the optional extra VGA-converter/upscaler board that you need to get video out from the Jamma to the G-Balance, you'd have to buy one from China and then spend absolutely ages getting it to work. Not worth it.

My advice is to just get a cheaper SEGA JVS 3 I/O, and not use the converter. Then just grab the 5v and ground from the first four ports on the Jamma-slot, and hook it up to CN7 on the Sega JVS. If you must have Jamma in your machine, get a JVS-to-jamma-converter. Way easier, and probably cheaper on the whole.
 
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I've now replaced the I/O in my G-balance for a Sega V3. The G-balance is NOT a standard pinout, at least on my loom. I had to test my way to the correct pinout (and there are still a few I don't know, though probably 12v power for lights and some other stuff, though EVERYTHING is working fine on mine), but I now got it working, just using simple Dupont-cables. I've posted a picture of the pins on MY loom, as well as where I connected it to on the JVS. Be aware that yours MIGHT be different... Especially if you go via your pin-converter. You might want to just connect one of the ground pins on whatever i/o you buy and simply test what each pin does. Also, if you use a Sega I/O you also need to connect pin 1 and 3 to eachother, and any other two 5v to pin 50 and 51 with a 100ohm resistor in the middle.

Oh, and if yours is the same and you figure out what 47 and 49-56 does...

EDIT since the last pic didn't quite make it...
 

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