A GPIO expander MCP23017 is used for managing all input from encoders and switches. Only I2C pins and GPIOs 25 & 27 are used.
It includes 3 standard MIDI ports (IN, OUT & THRU) with optional activity LED. UART pins (TxD & RxD) are used for this. All the 3 ports are opto-coupled following the scheme shared by @Imager
You can find the project files in the HW repository:
This is my first KiCad project and probably it’s a complete mess for a good electronic dessigner Anyway, i’m really happy with my new tool and i hope to bring more and better PCB designs to the community in the near future …
Great!! I think your project reached a professional grade sometime ago. Specially worth to mention is the fact that you accept to develop new feature requests which is an valuable extra.
No. It replace and extend the 2in1 PCB while improving and simplifying the wiring.
You still need the 4 controller PCBs, but soldering a JST connector instead of an angle-row-pin.
BTW, I’m working in an updated version of the mounting tutorial.