Gameboy Advance development page by Avelino Herrera Morales
Gameboy DMG-01 with Arduinoboy Midi Interface - MATRIXSYNTH
Uncommon Electronics - Super MIDI Boy V2 - Full MIDI Support, Link Port (DMG), Variable Clock, 1/8” Analog Clock Sync Out, RCA & 1/8” Stereo ProSound, CPU Clock Fix (to original Gameboy