difference between jvs and jamma

[purifuri]

What is the difference between jvs and jamma?? and what do you prefer?

[Franco B]

Probably not the best forum for this

Info taken from the Arcade Otaku Wiki:

What is JAMMA?

A wiring standard for arcade machines introduced in 1985 by the “Japanese Amusement Machine Manufacturers Association”. In this context, “JAMMA” refers to the wiring standard on the 56 pin JAMMA connector which consists of various inputs and outputs such as video, controls, credits etc. Most generic arcade cabinets produced throughout the ‘90’s are “JAMMA”.

Put simply, JAMMA is the interface you plug your game PCB into. One universal interface meant that arcade operators could add new games to existing machines when the old titles weren’t selling any more.

JAMMA+ refers too a slight variation on the JAMMA standard, such as an auxiliary harness for extra buttons.


What is JVS?

“JAMMA Video Standard”. JVS is essentially JAMMA 2. An updated standard created in the mid-to-late 90’s to improve upon JAMMA’s shortcomings. JVS uses separate connections. A HD-15 type video connection (commonly known as a VGA connector although this refers to a resolution really), RCA audio connections (stereo!), JST power connections (now with 3.3V!) and, perhaps most importantly, more advanced controls are handled via an I/O PCB within the cabinet which connects to the game hardware by USB cable.


So, how do I run JVS games in my JAMMA cabinet or vice versa?

Simple answer, with an I/O (input/output) board.

Running JVS in a JAMMA cab: There are two main types of JVS-JAMMA I/O used with Japanese machines, SEGA and Capcom. The SEGA I/O does not have a sound amplifier so you will need one separately if your machine doesn’t have a stereo amp. The Capcom I/O has a built in amp that converts to mono. It also has a CPS2/3 kick connector for ease of button wiring. So for ease of use, the Capcom I/O is pretty much plug and play whereas the SEGA one might save you a few quid if you have the right machine or extras.

The only other issue you should be aware of is power. A Naomi cartridge system will work on a JAMMA machine with an I/O but a Naomi GD ROM will probably not as it requires a JVS power supply. You will need to fit one separately, or alternatively some machines such as the Blast City and AWSD are JAMMA/JVS hybrids and come equipped with the necessary power connections. It is sometimes possible to power a Naomi 2 GD ROM system by turning the 5V line up fully but this is not advised as it could kill your I/O, or worse!

Running JAMMA in a JVS cab: Slightly simpler, a JAMMA-JVS I/O connects to your cabs JVS connections and you plug a JAMMA PCB into it. The ones to look out for are the Konami and Namco branded models for Windy II and Cyber-Lead, they will work with any JVS machine. River Service also make one. Remember though, if you don’t have a monitor that supports 15KHz, you’ll need some sort of upscanner/upscaler.