I have an arcade machine in a cabinet that doesn't work.

I got another board, but the pins didn't match - I figured out I needed to replace the wires.

I  bought a JAMMA harness, but everything was in Chinese.

Here's how I muddled through to installing the wires to the proper places. 

Step 1: What is JAMMA?

JAMMA is an industry-standardized layout for arcade game board connectors.  The name JAMMA stands for "Japan Amusement Machinery Manufacturers Association," and it became a de facto standard sometime in the 1980s.

The pins are labelled with letters and numbers
  • the component side is all numbers
  • the solder side is all letters
    • not including "i" or "o" since those are similar to numbers
    • starting with capitals
    • ending with lower case
Some notes on the pinout -
  • the connector has a "solder" side and a "component" side.  The "component" side faces the direction all the chips on the board do
  • "N/C" means "not connected" to any wires
  • The "KEY SLOT" is a notch in the JAMMA board.  The notch makes the connector asymmetrical so you don't connect the board upside-down.  Some connectors have a plastic piece here.
  • some games have 4 buttons, so pins "c" and "25" are these 4th buttons

About This Instructable


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Bio: Indie Film! Art science! Reuse and sustainability!
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