Good news, project is alive and goes forward :). PCB works and can show all those nice things from simulator, with subpixel font smoothing:
USB uploader also works. Very convenient for users - ST-Link/V2 not needed at all.
I started to write assembly manual. It's not complete, but enough to understand simplicity. Feel free to PR grammar fixes, because english language is not native for me :).
Minor tech notes
Found small issues, not enough to create next PCB version, but worth to remember for future works:
- LCD Backlight resistor should be reduced from 20 to 10 Ohm.
- Probably, backlight transistor not needed at all. It doesn't seem brightness needs tune. Also, this can be done via styles of LVGL widgets.
- It would be nice to increase size of TVD diode in dispense button filter. But it's needed only if you wish to attach pedal with long wire, and can be not mounted at all.
Plan is to learn how to use 3D printer, and print all plastic components (openscad drafts have been pulished on github. Then we can start debug dispense algorithm. Goal is to auto-tune on the fly all params (speed, retract level) via motor current sensor. But it's difficult to predict in advance, is it possible to to this with desired quality or not. I think, in 2-3 months we should get something final, ready to use.