Japanese Amusement Machine Manufacturers' Association

The Japan Amusement Machine and Marketing Association (Japanese: 一般社団法人日本アミュ一ズメントマシン協会), abbreviated JAMMA, is a Japanese trade association headquartered in Tokyo.

JAMMA is run by representatives from various arcade video game manufacturers, including Namco Bandai, Sega, Taito, Tecmo, Capcom, Konami and Atlus, among others.

Until 1 April 2012, JAMMA stood for Japan Amusement Machinery Manufacturers Association (社団法人日本アミューズメントマシン工業協会). The corporation was renamed after they merged with the Nihon Shopping Center Amusement Park Operator's Association (NSA) and the Japan Amusement Park Equipment Association (JAPEA).

Before 2012, JAMMA had been organizing an annual trade fair called the Amusement Machine Show for many years. In 2013, they began collaborating with the Amusement Machine Operators' Union (AOU), who had their own trade show, to promote a new event: the Japan Amusement Expo.

JAMMA is the namesake of a widely used wiring standard for arcade games. An arcade cabinet wired to JAMMA's specification can accept a motherboard for any JAMMA-compatible game. JAMMA introduced the standard in 1985; by the 1990s, most new arcade games were built to JAMMA specifications. As the majority of arcade games were designed in Japan at this time, JAMMA became the de facto standard internationally.

Before the JAMMA standard, most arcade PCBs, wiring harnesses, and power supplies were custom-built. When an old game became unprofitable, many arcade operators would rewire the cabinet and update the artwork in order to put different games in the cabinets. Reusing old cabinets made a lot of sense, and it was realized that the cabinets were a different market from the games themselves. The JAMMA standard allowed plug-and-play cabinets to be created (reducing the cost to arcade operators) where an unprofitable game could be replaced with another game by a simple swap of the game's PCB. This resulted in most arcade games in Japan (outside racing and gun shooting games that required deluxe cabinets) to be sold as conversion kits consisting of nothing more than a PCB, play instructions and an operator's manual.

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