This is the kind of project that you are going to do because you are bored. You will not need to do this project ever. This is just for entertainment. So. Materials required:
Any small cardboard box(max 7x7x7)
At least ten alligator wires
A hobby knife
A Mac(Windows may be possible, I don't know.)
ROMs to be emulated
Time required: 15-30 minutes
Step 1: Assembling Materials
This project WILL NOT be very organized. At least, the inside of the box won't be. So make sure you have everything. Pretty simple, right?
Step 2: Cut Various Holes
You will need to cut at least seven holes in your box. Five for the buttons, one for the ground lead, one for the line to the computer. Or you can thread the wires through the lid. Again, this is a simple step, but it's very important.
Step 3: Making Buttons
You will need five buttons. Up, Down, Left, Right, Fire. The buttons should be a maximum of 1.5"x1.5". Also, you should probably make a bracelet out of tinfoil while you're at it. The buttons should have little pointy bits on the bottom to go into the holes. Fold tinfoil into an appropriate shape and out int into a hole.
Step 4: Connecting the Buttons to the MaKey MaKey
You will need your alligator wires for this. You should, INSIDE the box, attach one end of the wires to the pointy part of the buttons. Attach the corresponding ends the the corresponding holes.
Space = Fire
Up Arrow = Up
Down Arrow = Down
Left Arrow = Left
Right Arrow = Right
Also, attach any part of the bracelet to any of the 5 ground(Earth) holes.
Step 5: Setting Up the Software
Download OpenEmu Experimental Version from here: https://github.com/OpenEmu/OpenEmu/releases/downlo...
Download Atari ROMs from here: http://www.emuparadise.me/Atari_7800_ROMs/47
Drag the ROMs from your downloads folder directly into an OpenEmu window. They should install.
Step 6: Finishing Up
Hit command-comma to bring up the OpenEmu preferences. Go to the controls tab and select Atari 7800. Change the controls so that they match the list in step 4. The other controls won't matter.
Step 7: Have Fun!
That's all folks. This is a HIGHLY moddable project, just please reference the original if you mod it. Some suggestions are:
Use two MaKey MaKeys for two-player fun
Paint the box to look like a controller
Use actual buttons somehow