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What's the right way for Jamma connection?

antonioad14(TWON)

antonioad14(TWON)

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Hello! I got a CPS2 system and a Supergun somewhat recently, but unfortunately the supergun I got had a plastic casing that wouldn't let the supergun and CPS2 make a connection with the Jamma connection. So I decided to get an extension to fix this problem, but I have one question how do I know which side is the correct one? I heard if you plug the Jamma in upside down it can cause problems, so don't wanna risk it.
 

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Typically there are thicker wires at one end, that's the power end, and that goes to the shorter end of the JAMMA connector.

If that extension is just straight through, then you won't damage anything by plugging it in the wrong way (because both ends are wrong, instead of one being wrong and sending power to the wrong pins). But it won't support every feature because of the missing wires.

Once you figure it out, consider labelling it or cutting a notch into the card edge, etc, so you don't have to think about it too much every time.
 
NFGx said:
Typically there are thicker wires at one end, that's the power end, and that goes to the shorter end of the JAMMA connector.

If that extension is just straight through, then you won't damage anything by plugging it in the wrong way (because both ends are wrong, instead of one being wrong and sending power to the wrong pins). But it won't support every feature because of the missing wires.

Once you figure it out, consider labelling it or cutting a notch into the card edge, etc, so you don't have to think about it too much every time.
Click to expand...
Thanks, amazing explanation. gonna give it a go sometime Tommorow.
 
I need to clarify that you won't wreck anything if you put both ends wrong. So if you think "thick wires long edge" (which is the opposite of what I said) and do that on both sides, you'll live to tell the tale. If you just guess and do one end right and the other wrong, you'll risk letting the magic smoke out of something.

But yeah, the power side is always the thick side - but there's no guarantee anything will be thicker. Some harnesses are, some aren't. It looks like yours has one thick wire to two power pins, on your connector, and there's no -5V.

If your board doesn't have a key on pin 7, (either a missing pin or a physical block of some kind) then look at the circuits on that board - they'll usually be joined together, or thicker, or grouped together in some way, on the power end. On the opposite end, the last two pins on both sides are ground, so they'll often look different too - but only two pins instead of six.

Also, usually, there'll only be a via (a small pipe that connects one side of the board to the other) connecting both sides of the power pins: ground, +5V, -5V, 12V. None of the other pins will do this, as a rule. Of course on a CPS2 you can't see the board, but this would help with anything that's not in a case.
 
From your picture you can clearly see the thicker (power) wires which are on the 'short' end of the key and on the other side loads of thinner wires for controls, video and audio.

I would recommend inserting a key in #7 and cutting a nudge in the fingerboard at position #7 so you cannot reverse it

1747823811428.png



1747823854513.png
 
PascalP said:
From your picture you can clearly see the thicker (power) wires which are on the 'short' end of the key and on the other side loads of thinner wires for controls, video and audio.

I would recommend inserting a key in #7 and cutting a nudge in the fingerboard at position #7 so you cannot reverse it

1747823811428.png



1747823854513.png
Click to expand...
There’s a hole thread of people putting them in the wrong way. Myself included. It sucks by the way.
 
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