I circuit bent a Sega Genesis for MIDI-controlled glitch visuals. I can hook it up to a DAW or MIDI sequencer and then glitch out a game in sync with music.
I put this together a few years ago, but had some questions about it, so I cracked open the game system to show how it works. All I’ve done is set up some places to short out the VRAM, where the Genesis stores the sprites for the graphics. Then I added an Arduino to control when it short them out (triggered by MIDI).
Keep in mind that not all Genesis systems are the same, they have different board revisions, so your Genesis might have things in different places.
Sample output: