2PLAYERs Gameboy Modding Tutorial
Recently I have been doing some tinkering with my gameboy as well as some other systems I got at local thrift stores and ent shops. I am by no means a pro at this but I have managed to make some interesting tools for my studio. Mostly I deal with MIDI synths but this mod will show you a couple options that can be used with just a gameboy. Specifically, a gameboy pocket. So, LET’S BEGIN!
All you really need is a Gameboy and an NES. Basically, I have modified the arduinoboy code to output through the gameboy pocket and directly into the NES to make use of the 2A03. I havent made use of the expansion chip yet but i am working on it.
So here is the underside of the NES
Now the reason why you see a Sega in the picture up top is because i figured out a way to access the FM chip through the NES and gameboy pocket as well! Start by soldering a ribbon cable to the 2A03 as seen here:
Next those lines will be soldered to the logic chip and FM chip of the Sega. Note that it needs to be a model 1 genesis because the FM chip is integrated in later models and i havent figured those logic chips out yet.
Now both systems are connected!
But what is the point if you cannot control them? Enter in an arduino!
I modified the arduino to connect to an old IDE cable i had laying around. This is why you need a gameboy pocket. The IDE fits perfectly into the game slot! and we can take 5V from there to power the arduino.
The IDE cable i used has 3 connections, so in theory i could connect another gameboy pocket. But with everything else already going on i figure i should start small and then add another. Technically i believe adding another gameboy will introduce some latency and you would have to start offsetting notes to get everything to play on time. I wasnt too thrilled about that.
Next we add some obligatory wires on a breadboard with a couple resistors and an LED. My favorite color wire is green because it conducts information more eco-friendily. The red wire is hot, so dont touch that one.
I am not really sure what this stuff does but it works when hooked up. It was part of the arduinoboy spec so i figured it should stay around. We can then connect the red and black wire to a NES joystick to help in altering the FM sythesis channel modulation frequencies. i just plugged them into the screws at the bottom and that did the trick.
Also i stuck this DMG screen into the sega so i could see which sound properties i was fixing with the joystick. This is optional but you could prosound it first. Its not back lit but the sega outputs color so this is basically now a gameboy color screen. WARNING: you cannot revert to standard DMG screen colors after doing this mod.
After adding the NES screen i got a little over excited and added a screen to the arduinoboy to output the NES video signal. I had this old laptop screen hanging around so i figured it should be used. This was done by cross wiring a signal variable into the 555 timer on the arduino board. Google this mod, it is very common and relatively easy.
Now everything is almost ready to start making music!
The last step is completly optional but it gives you a bunch more channels and unlocks some OPL3 as well. Simply take an old creative sound blaster (Note: it has to be an ISA card or it will not function properly) and plug it directly into the sega. Since OPL3 is a derivative or the FM chip in the Sega you simply need to do an intergral algorithm and you can use it. Presto! You have all you could ever need sound wise running off just one gameboy pocket! The battery life isnt too great but you can always plug into a wall.