And now for something a bit different... A Supergun!

[glitch77]

I am building myself a nice supergun (for those out of the loop, a supergun is a 'black box' that connects to a JAMMA board and gives you controls, and a TV-output. Effectively making any JAMMA board a home console instantly.)

But this thing has a twist; It can be played with no TV.

The top of the SG will house a 5" LCD screen, which via a RGB to NTSC converter, will display an almost perfect picture. There will also be internal speakers for stereo audio. It will also have L/R audio, and S-Video outputs, so that you can easily hook it to a television.

It will also be the smallest Supergun that I think I have ever seen. 8" wide, 6" deep, and about 5" tall, which when you think about an arcade power supply being over half that size, room begins to be an issue quickly.

I am about 40% there. All power wiring is done, the JAMMA interface is ready, the controller port (havent finalized the actual controllers yet) is ready, power supply is ready, and about 3/4 of the mounting is done. The hardest part that I lack is finishing the RGB to NTSC converter. They can be easily obtained for about 100 bucks, but can be built for just a few bucks, and LOTS of knowhow.

I will try to get pics of the work, but will definatly get some of the finished SG.


Technical stuff:

Power - AC is taken in by a standard computer cord and socket (easiest way to socket the power cord, looks good too.) The power supply is just some old one I had, puts out +12v [2 amps], +5v [12 amps], -5V [1 amp], and GND.

Controls - Each player will have U,D,L,R, BTN1, BTN2, BTN3, BTN4, Start, and Coin. This will work for everything but 6-button street fighter, which could be added later be soldering up some more wires. They will connect using one 25-pin printer connector. Both controllers will use a single plug.

Controllers - I am debating about this heavily. I think at first, I will be using SNES controllers that have been customized to use an arcade style hookup (one wire per input). Later, I could easily make new controllers of different types, using the same connector. But for now, I would like to keep it "on the couch with friends" style, with lightweight, familier controllers.

Video - S-Video out. 5" built in LCD. (Toshiba TFD50W32B)

Audio - Unknown. L/R audio out.

Cooling - Internal 2" 12v fan running at 7v for silent operation.


---- RGB to NTSC ----
For the conversion, I am using an AD725 chip from Analog Devices. It is surface mount, so I did have to order a SOIC-16 to DIP adapter to make things easier (only 6 bucks at Digi-Key). I dont know if I have the expertise to actually finish this thing, and may have to break down and buy a pre-fabbed one, but I am going to try my best. I have been able to track down most everything I need (crystal, resistors of all types, loads of capacitors, etc) with my limited skills, so we shall see!

[flampoo]

I've always wanted a supergun for a NG system. This should be cool.

[Stingray]

I look forward to seeing your progress. I've been considering doing a supergun myself, but I need to do a lot more research on it before I decide if I want to do it or not.

-S

[teetu]

I actually got into the whole BYOAC by making a supergun.

did u think about using a psone lcd screen?  I know they are a bit pricey, but u won't need a RGB>NTSC converter.  Their picture is fantastic!

[glitch77]

I am using a PSone screen, but it is a cheap-o that doesnt accept pure RGB. This isnt a big issue though, because for the TV-out, I have to have the converter anyhow. So its allright. The screen was in the clearance bin for 20 bucks about a year ago.

I am wiring up the converter now. Will post results soon!

[CthulhuLuke]

make sure to post the circuit layout of your rgb to ntsc convertor as well  I'd really be interested in putting one of these together this summer, but the rgb to ntsc convertor has been a major drawback.  I even have a fully functional power supply plus a jamma harness, I'm all ready!
    -end results should be pretty awesome, when I was in japan they had some neo geo carts going on little 7" lcd screens, IT KICKED SERIOUS ASS!

[glitch77]

Just got through with the first version of the RGB-NTSC converter.... Roasted the first chip, bigtime.

If chip 2 doesnt work out, I might have to abandon making my own... I hope not.

[glitch77]

Below is a schematic for the RGB->S-video chip. The only thing that isnt on there is the Oscillator that hooks to the 4FSC pin. It is a 14.318180 MHz OSC that only needs 5v and Gnd to work, the output pin of the OSC runs into 4FSC. The Chroma and Luma for S-video are the pins on the opposite sides of the composite out, and require the same 220mF capacitor, and 75ohm resitor.

[glitch77]

The chips can be found here:

http://www.analog.com/Analog_Root/productPage/productHome/0%2C2121%2CAD725%2C00.html

They do not, not, offer free samples.

[glitch77]

I re-wired the chip and hooked it up with no sync input on 4FSC, and got alot of mumbo jumbo on the screen (good thing!), and didnt nuke the chip. It must have been a short somewhere I couldnt see.

Anyhow, once I get the oscillators and coils in, Ill post up.