SEGA MASTER SYNTH
BASICALLY A LITTLE SCALE MASTER SYSTEM MIDI CONVERTER, WITH A 16 KNOB MIDI INTERFACE.
link to little scale :- http://little-scale.blogspot.com/2012/12/how-to-build-sega-master-system-midi.html
below is the code for an arduino mega. it has midi thru, and it is based on the NOTES and VOLTS midi interface project.
for more info on this code check it out here :- https://www.notesandvolts.com/
Basically add arduino midi input, and midi output circuits (search them up youll find a schematic) Then add knob switches as below :-
16 x POTENTIOMETERS (10k) LEG 1 to GND, LEG 2 to the below pins, LEG 3 to 5V
A0 = NOISE CHANNEL VOLUME
A1 = PULSE CHANNEL 1 VOLUME
A2 = PULSE CHANNEL 2 VOLUME
A3 = PULSE CHANNEL 3 VOLUME
A4 = VIBRATO DEPTH CHANNEL 1
A5 = VIBRATO DEPTH CHANNEL 2
A6 = VIBRATO DEPTH CHANNEL 3
A7 = VIBRATO AMOUNT CHANNEL 1
A8 = VIBRATO AMOUNT CHANNEL 2
A9 = VIBRATO AMOUNT CHANNEL 3
A10 = AMPLITUDE DEPTH CHANNEL 1
A11 = AMPLITUDE DEPTH CHANNEL 2
A12 = AMPLITUDE DEPTH CHANNEL 3
A13 = AMPLITUDE SPEED CHANNEL 1
A14 = AMPLITUDE SPEED CHANNEL 2
A15 = AMPLITUDE SPEED CHANNEL 3
SWITCHES, PIN 1 TO GND and PIN 2 of the switches to :-
D17 = AMPLITUDE ENGAGE CHANNEL 1
D16 = AMPLITUDE ENGAGE CHANNEL 2
D15 = AMPLITUDE ENGAGE CHANNEL 3
D20 = VIBRATO ENGAGE CHANNEL 1
D19 = VIBRATO ENGAGE CHANNEL 2
D18 = VIBRATO ENGAGE CHANNEL 3
D21 = BASS MODE
you can change around the pins, becausde the above is rather none sensicle, i built this machine before i coded it, and in only a few hours so it was rather oddly laid out.