Most of us who play an occasional arcade game will have never taken a look inside a cabinet however much its contents might interest us. We’ll know in principle what kind of hardware we’d expect to see if we were given the chance, but the details are probably beyond us.
In fact, there is a standard for the wiring in arcade cabinets. Arcade operators demanded running costs as low as possible, and the industry responded with the JAMMA wiring standard. The Japan Amusement Machinery Manufacturers Association was the name the Japanese trade body was known under in the 1980s, and they originated a specification for both wiring and connector that would allow hardware to be easily installed for any game that supported it.
[Jochen Zurborg] has created an interesting board supporting the JAMMA connector, one that interfaces it with a Raspberry Pi and offers full support of the Pi as a video source. He’s launching his Pi2Jamma as a commercial product so sadly there are no schematics or Gerbers for you to look at, but if you’d prefer to roll your own it probably wouldn’t be beyond most Hackaday readers to do so. What it does though is open up the huge world of emulation on the Pi to owners of classic cabinets, and if you don’t mind forking out for one then we can see it might make for a very versatile addition to your cabinet.
We’ve featured [Jochen]’s work before here at Hackaday with a joystick that faithfully replicates arcade items. As to the Pi, this is the first JAMMA board we’ve seen with video, but we’ve featured another board using a Pi to bring console controllers to JAMMA boards in the past.
Uh! Jamma Pi
Stahp.
pfft. raspberry jamma.
… were you going for the oblique “raspberry pyjama” ? because if so, <applause>
raspberry jamma, a pun on raspberry jam and jamma.
already been done
http://www.aussiearcade.com/showthread.php/67986-JAMMA-board-from-Raspberry-PI
Thank you! There’s no way I’d pay this much for a board like this
I think the aussie one works out more expensive than the one listed here on browsing for the kit prices on that thread…
This isnt aimed at makers, this is aimed at the market that buy’s blue elf’s and the like and run x in one game boards in stock cabinets, for that 130e is probably positioned just a tiny bit cheaper than the x in one box nearest it, however I fear that market is rather saturated.
I’ll more than likely roll my own innards one day as I have some cocktail cabs using JAMMA and occasionally I swap original boards into them although I have replaced my screens with portable crt tv units already when the originals went bad so can just feed the composite in without any conversion, but soldering wires onto a jamma connector isnt that much fun, so if it was under 90e I’d probably just spring for one…
The hardware isn’t the magical part. The wow is that somebody figured out how to get the RPi3 to output 15KHz/60Hz video without laggy VGA to CGA framebuffering/etc. Once somebody else figures it out and releases the source nobody will buy this. While the author deserves credit for being the first to accomplish this, the price for the hardware/software seems out of touch for the Raspberry Pi crowd. I don’t want to see the author get screwed by having somebody release his code without permission because he deserves some compensation. I’d pay $50 USD for the image that sweet-talks the video hardware to speak 15KHz but 129 Euros plus shipping to the USA is too rich for my blood. Maybe if you want to emulate rare/prototype games this would be an affordable solution but for now I’ll stick with my genuine PCBs.
I’ve been waiting for somebody to do this for years. Since the RPi can output composite video 15KHz RGB was just hiding somewhere in the hardware waiting to see daylight.
I was very curious about how they were getting RGB video off the Pi header. Looks like they’ve just taken https://www.raspberrypi.org/blog/gert-vga-adapter/, added some shifters, audio amp and a jamma edge connector. The software side will be interesting though. At least it (should be) low cost.
Thanks for looking it over. I expected it to use the RPi’s onboard video instead of bitbanging if that is the correct term. Months ago I bought a Cubieboard in hopes I could dive in and tweak the VGA to sync down to CGA but work has sucked every iota of free time from my existence.
I wonder if the software also includes consoles like the NES and Genesis. Getting RGB quality lag free NES 15KHz video out of an RPi would be pretty awesome.
It’s not bitbanging, it’s using the DPI interface from the SoC and using a resistor ladder as a DAC. 15khz is definitely doable – see https://youtu.be/gjUBQKyeWlQ.
15KHz/60Hz video out of pee is nothing special, rgb DPI interface can do some crazy things like directly driving sony PSP LCD screen.