Arduino can be built with C20/C++20 or C17/C++17 by switching to the latest gcc-arm-none-eabi. Below shows 2 different ways one using arduino-cli and the other using a Makefile included in this repo.

The REBL_UI offers a simple way to build a user interface with a Rotary Encoder, a Button, and an LCD. Currently it is set up for 16x2 LCD, but could easily be changed to whatever. It includes a very ...