and the code, https://github.com/elkayem/midi2cv
I use a dual opamp and a single dac, because i only need note and velocity. The opto i use is, H11L1
It works but has a strange issue that i can not figure out.
The author says the code supports midi notes from 21 to 108.
When I send midi notes to test the device,
(Arduino powered with +12, TL082 Opamp powered with +15 to GND )
The notes <= 36 gives +15V in the output of the opamp. The note 37 gives +3.43V The note 38 gives +1.7V . . .then it increments as expected until note 108 which gives +7.52 V
Also to add I have +1.5V DC offset on the both outputs of the opamp. (This, i can live with but i would love it not to happen. )
I would be very happy if you help me on this, thank you.