JAMMA and Interfaces

[jvendryes]

I was reading about interfaces on the Step-by-Step guide (http://arcadecontrols.com/arcade_newbie4.html). A lot of good information, gave me a few noob questions:

Is that guide assuming you are using MAME rather than JAMMA?
Is it different for JAMMA?
Does "ghosting" or "blocking" happen with a JAMMA setup rather than MAME?

Thanks!

[Beretta]

yes, this is assuming you are using mame or some other emulator, there for you need a way of interfacing to a pc.


jamma on the other hand is a standard interface for arcade games.. i dont remember when it became a standard.. before the jamma standard games had their own propitiatory wiring.

the jamma standard is nothing more then a wiring harness, this is so you can plug in any jamma board in a bout 3 seconds.

jamma handles everything, sound, controls, video, power, all in one convenient edge connector.

think of the jamma interface as an older console.. like a nes, snes, or genesis.

and the jamma arcade board as the video game "cart", they're not compatible mind you but this gives you an idea of how simple it is to change games using the jamma interface.

PC's do not use jamma, as i said this is a wiring harness.. if you so desired you could wire your controls using a jamma harness.. however you would still neeed to use one of those methods for actually interfacing from the pc.

there is no ghosting on jamma because arcade games was made for those buttons to be pressed at once.. ghosting really only happens on keyboard hacks because most keyboards use a "matrix" for key presses.. so there are far fewer actual inputs on a keyboard then there are key's on a keyboard.

for example on a keyboard the "A" key is not equal "input #1", it instead would probably be "input #1 + input #2" and the same for most other key's on the keyboard..

in normal use this is not a issue, however for hacking you quickly run into the limitation that the matrix has, and that is if you press the right (or wrong) keys you can get into a situation where 3 key presses generate a phantom 4th.. on most keyboards these days ghost key's are'nt much of a issue.. it's usually a problem of blocking.. thats because the keyboard knows which key's will generate ghost key's so instead blocks all input, this stops ghosting but does'nt solve the problem of not being able to hit X,Y,Z together.