Sega 838-13683-02 help

[hjrcustoms]

Hi Everyone,

I am currently running a Naomi 2 (not in a cab) and trying to use the 838-13683-02 board for jamma conversion. I am having issues with it registering credit presses from the harness. Not sure its an issue with the board itself or if the cabinets run something else for credit detection.

Thanks,

Ben.

 

[clintkolodziej]

Did you ever solve this? I have the same issue with a Naomi 1 with the same IO board. Credit doesn't work, also Directionals are all stuck high on the JVS test. I read a few places that without a coin meter this board has issues, there is talk of wiring the coin meter pin on the jamma edge to +5v with a 100ohm resister in line to spoof that. Apparently what I read without the coin meter this board, and other Sega IO boards won't register inputs. For me Test/Service/Start/B1-B5 all work as is.

 

[hjrcustoms]

No luck unfortunately, I had a quick search but couldn't really come up with anything, so its sitting in the too hard basket at this point to be revisited at a later date.

 

[nam9]

You need to spoof the coin meter on these I/O boards. It’s as simple as adding a resistor as @clintkolodziej suggested:

 

[clintkolodziej]

I did this on my board and got it working. I was also having some really odd issues with my fight sticks going native DB15 to my HAS, directions weren't working and on one stick diagonals mapped to the credit button. Really odd. When I hook my sticks up with USB into undamned usb decoders everything is working 100%. I may remove the coin meter mods to see if things still work without them through the UD decoders - I kind of did a quick solder job anyway so if they are needed permanently I'll redo them. If I find anything more I'll post my results.

I used 120ohm resistors, I saw something where an official Sega document mentioned to use that resistance, can't remember where I saw it though but anecdotally others say 100ohm works as well.

 

[hjrcustoms]

Thank you both, added the resisters and credit input all working.