Hi @guys!
The MCP4728 (DAC) code is working like a charm, so … CV-OUT is implemented, and also CV/Gate for IN & OUT:
- CV/Gate IN & OUT is mapped to/from MIDI-Note on/off
- CV IN & OUT, that can be mapped to/from MIDI CC, Pitch Bending & Channel Pressure.
Development branch “cvgate” has been created on 3 repositories:
- zyncoder
- zynthian-ui
- zynthian-webconf
Webconf’s wiring tab has evolved a little bit for fitting the new requirements, including the implementation of a “form reload on-change mechanism” that can be used for making forms more dynamic & reliable.
Finally, regarding the CV/Gate to/from MIDI-note translation, currently all available voltage range is used on Input and Output, and notes, from 0 to 127, are distributed linearly on this voltage range. If you connect zynthian’s CV/Gate OUT to zynthian’s CV/Gate IN, you should get a nearly perfect MIDI-analog-THRU 
For improving integration with other CV/Gate devices, some kind of scaling mechanism, configurable from webconf. should be implemented for CV IN & OUT.
Enjoy!!