First, here is a bit of history behind the meaning of the acronym, JAMMA.
In the dark ages of the Golden Age of arcade video games (1984 and earlier), game makers operated in small exclusive domains where they designed game components in ways that best served their own interests.
Consequently, each had its own proprietary circuit boards, power supplies, and wiring harnesses. Essentially, there was no interchangeability of components between one manufacturer’s gaming cabinet and a gaming cabinet made by someone else.
Thanks to the Japanese, around 1985, all that exclusivity vanished. The Japan Entertainment Machinery Manufacturers Association (JAMMA) created some industry standards, particularly for the design of gaming printed circuit boards (PCBs). And, things changed forever.
The most important and influential of these new standards was the standard PCB pinout. Any gaming PCB that meets that pinout standard is what we now call a JAMMA board. You can see the JAMMA logo stamped near the pinout section of a JAMMA board. Almost all JAMMA decks sport that logo.
The wiring that connects the components of the game: monitor, power supply, control panel, speaker, etc. – the PCB is called a JAMMA wiring harness. The wiring harness’s 56-pin edge connector sits on the pinout fingers on the PCB.
There are many JAMMA terms that we often hear and use: JAMMA board, JAMMA harness, JAMMA edge connector, JAMMA cabinet, etc. At the root of its meaning is nothing more than the concept of PCB interchangeability between cabinets. different manufacturers
And it’s JAMMA’s standard PCB pinout (graphic below) that has made it all possible.
The following JAMMA pinout chart is basically a map of the 56-pin edge connector of the JAMMA wiring harness. When properly seated on the PCB, the edge connector pins will align with the PCB’s pinout fingers and your game will play.
When you shoot a game, you can plug and play the JAMMA PCB for your next favorite game. Plug-and-play simply means unplugging the edge connector from one PCB and plugging it into another PCB.
And that plug-and-play process can go on and on, because there are now thousands of JAMMA gaming PCBs you can play on your JAMMA cabinet. Thank you, Japan.
JAMMA PIN CHART
Solder side – Alpha characters – 28 pins – AZ, af
The solder side is the bottom side of the PCB. It is the side where the welded connections of the parts are exposed to view. Few pieces, if any, are located on the weld side. The solder side pinout is identified by alphabetic characters.
Parts Side – Numerical Characters – 28 Pins – 1-28
The parts side is the top side of the PCB. It is the side where the pieces are located. The part side pinout is identified by numeric characters.
Usually the printed circuit board is printed and the edge connector is embossed with the alphabetic and numeric characters.
EARTH – A, 1
EARTH – B, 2
+5VDC-C, 3
+5 VDC-D, 4
-5 VDC – E.5
+12 VDC – F, 6
KEY SLOT – H, 7
COIN COUNTER #2 – J
COIN COUNTER #1 – 8
LOCK COIL #2 – K
LOCK COIL #1 – 9
SPEAKER (-) – L
SPEAKER (+) – 10
N/CM
NC-11
GREEN VIDEO – N
RED VIDEO – 12
P-VIDEO SYNCHRONIZATION
BLUE VIDEO – 13
SERVICE SWITCH-R
FLOOR VIDEO – 14
TILT SWITCH (SLAM) – S
SWITCH TEST – 15
CORNER SWITCH #2 – T
CORNER SWITCH #1 – 16
PLAYER 2 – START – U
PLAYER 1 – START – 17
PLAYER 2 – UP – V
PLAYER 1 – UP – 18
PLAYER 2 – DOWN – W
PLAYER 1 – DOWN – 19
PLAYER 2 – LEFT – X
PLAYER 1 – LEFT – 20
PLAYER 2 – RIGHT – Y
PLAYER 1 – RIGHT – 21
PLAYER 2 – BUTTON 1 – Z
PLAYER 1 – BUTTON 1 – 22
PLAYER 2 – BUTTON 2 – a
PLAYER 1 – BUTTON 2 – 23
PLAYER 2 – BUTTON 3 – b
PLAYER 1 – BUTTON 3 – 24
NC-c
N/A – 25
N/Ad
N/A – 26
EARTH-e
EARTH-27
EARTH -f
EARTH-28
Understand the JAMMA pinout diagram:
N/A – Without connection.
key slot – A keyed slot that aligns with a skip in the pinout section of the PCB.
This safety feature is provided to ensure that the power section sits at the correct end of the pinout section. If the edge connector is reversed and the power section sits on the wrong or opposite end, it can cause irreparable damage to the PCB.
If the edge connector key has been removed, mark the connector on the “parts side” to help ensure proper seating.
power section – AF pins, 1-6, e, f, 27, 28
video section – Pins N, P, 13-15
corner section – Pins J, K, T, 8, 9, 16
Controller section (joystick) – VY pins, 18-21
Button switch section – ZB pins, 22-24
