mini MIDI to CV converter with Gate and Trigger outputs

[Mickeyluv]

Thanks for the reply - It looks to be exactly what I need. I've got my guitar controller breadboarded and working, but the CV output isn't accurate enough with the circuit I'm using for the MIDI to CV (PIC with 8-bit DAC) and this looks ideal.

EDIT: I've just replaced the original MIDI to CV converter with the Arduino setup. It's perfect for guitar. The next stage is to build up a permanent module for my synth. Thanks for the effort that went into developing this - much appreciated.

[Mickeyluv]

I hope it's OK to post again here after such a long time, but I have a question about how the DAC values are calculated and I want to understand this more thoroughly for another idea I'm working on. I've shown the first octave of the DAC table here from the .ino for clarification. As an example, the DAC output for 0.0833 volts is given as 62. My thinking is the output would be 62/4096*5=0.076V and so on for all DAC values given. In practice the output sounds in-tune, so my reasoning must be flawed, as the closest value to 0.833V would be DAC68 at 0.830V with my calculation.

What am I missing?

DAC note CV
-----------------------
0, // 0 0,0000 V
62, // 1 0,0833 V
140, // 2 0,1667 V
202, // 3 0,2500 V
276, // 4 0,3333 V
340, // 5 0,4167 V
411, // 6 0,5000 V
478, // 7 0,5833 V
546, // 8 0,6667 V
616, // 9 0,7500 V
682, // 10 0,8333 V
754, // 11 0,9167 V

[kkissinger]

[PHOBoS]

[Mickeyluv]

Thanks for the replies. I'm working on a project to convert an audio square wave to 1V/Oct. The DAC value will be calculated from the instantaneous frequency and be continuously variable rather than quantized. Maybe this will be too slow in practice - I don't know yet.

Understanding how the DAC values were arrived at in the Midi to CV convertor is a great help.