Based on my earlier MIDI to CV clone of the Elkyam MIDI to CV using MCP4822, these are in short supply so I swapped them to MCP4922

This repository contains the code and schematic for a DIY MIDI to CV converter. I installed this converter into a home-built analog synthesizer.

• The MIDI to CV converter includes the following outputs:

• Note CV output (88 keys, 1V/octave) using a 12-bit DAC

• Note priority (highest note, lowest note, or last note) selectable with jumper or 3-way switch

• Pitch bend CV output (1.0v /- 1.0V) octave up or down

• Velocity CV output (0 to 5V)

• Control Change CV output (0 to 2V) suitable for a CEM or AS based VCA

• Aftertouch output CV (0-2V) can be increased with an opamp like the velocity.

• Trigger output (5V, 20 msec pulse for each new key played)

• Gate output (5V when any key depressed)

• Clock output (1 clock per quarter note, 20 msec 5V pulses)

• Read the MIDI channel from 4 toggle switches, can be replaced with a HEX rotary switch or bank of 4 dip switches.

• Really needs a 4096mV reference for the AREF pins and recalibrating.

When building and testing the Elkyam MIDI to CV I noticed the voltage was out and it seems he subtracts 21 from the note, I removed this and fixed the bottom note failure. I also added 4 toggle switches so that I could change the channel from OMNI to 1-15 (not 16 unfortunately)