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Pin setup G-Balance JVS I/O

Urabutbl

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Does anybody have the pin config for the G-Balance JVS i/o? It's sadly not in the G-Balance manual.

My GFI I/O is fried, so I'm replacing it with a Sega V3 i/o, but I suspect that some of the pins are slightly different - at the moment my Naomi recognizes the Sega i/o and starts up, and loads into Guilty Gear, but despite looping pin 1 and 3 on the Sega v3, I can't seem to get any inputs going. First problem is I can't coin up, by service button or coin chute. I know I also need to "fool" the card that there are coin meters present, but the thing is that there IS a coin meter on the G-Balance. It seems to attach to pin 49, which is just as it should be. My problem is that since the test button won't work either, I can't figure out what any of my inputs are doing... so I don't know if the card pin layout is completely different, or my soldering is bad (it is, but I mean non-working bad).

Anyway, would greatly appreciate it if anyone had the pin configuration for the GFI I/O :)
 
Test and service buttons are on the Naomi motherboard, use those.

Check that the inputs on the IO are actually working. Remove the 60-pin harness, loop pin 1 and pin 3, then connect a GND (pins 9-15) and 1P start button (pin 17) together. See if you can start a game.

The pinout for Sega IOs is here:

http://triplemoonstar.brinkster.net/theshed/default.asp?stockid=2532

If the IO is working, just meter out the harness with a multimeter and see where each pin leads to. You can then repin the connector as per the Sega pinout (if needed).
 
First off, thank you; I can't believe I've owned a Naomi for this long (and even took it apart to clean it and change the chassi fan) without learning there were test and service buttons on it. Never needed them before I guess.

2nd, I'm at a complete loss now. Just to see if I could get any input, I looped pin 1 and 3 straight in the socket, and connected both coin meters (pin 49 and 50) to 5v pins (5 and 6) using a breadboard with 100 ohm resistors so I can't blame my wiring. But even if I run a cable straight from a button to the I/O, I get no input (I've obviously tried several different ones from the harness as well)! Am I missing something blindingly obvious in my ignorance?

It should be mentioned that in the test menu, the Naomi correctly identifies the sega I/O, and all the values are 0:ed out (the coin values change to from 0000 to 8000 if I remove the coin meter-cables) EXCEPT for the Analogue values, which are jumping like crazy - they stabilize if I remove the USB cable from the Naomi. My only hypothesis is that I've been sold a duff Sega I/O, and that the analogue values are somehow overriding the digital inputs.

Any ideas? I'm tearing my hair out here.
 
With a JVS Type 1:

sega_jvs_io_loopback.jpg

+5V to CN7 / CN8
JVS cable connected
Jumper between pin 1 and pin 3 on the 60-pin connector

If I touch GND and an input together I get a reading on screen. At no point are the analog values jumping like crazy.

You might have just gotten a duff unit.
 
Yeah, definitely a broken unit then :(

Thank you so much for confirming it for me though, I could've spent hours and days tinkering, convinced I was going wrong somewhere.
 
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