On Division 6
"This tiny board lets you add a MIDI port to just about anything.
Can be installed directly into a GBA, GBA-SP, DS or DS Lite, or with some extra parts you can interface it with other devices.
* 12 outputs
* Outputs can be active-high or active-low
* Map any MIDI note to any output
* Mono and Poly modes
* High-note and low-note priority modes
* Assign to any MIDI channel or Omni
* Pause mode ensures that first note is released before next is played
* Board dimensions: 1.04" x .4"
* Power supply: 3.3v-5v
* Includes 2.5mm phone jack for mounting in small devices"
via Deviant Synth. The MIDIFY board is the small blue board in this image.
Click on the Division 6 label link below for prior posts including video including one of a microwave oven being controlled by a MIDI keyboard.