emulator
========
to run emulator you need installed.
then `cd src && ./run_emulator.sh`.
hardware
========
to compile firmware use .
you need to create python venv or something, and then `pio run` will create firmware file.
schematic is in diagram.json, use to display.
most of the stuff you can also see in platformio.ini, other than that connect button from pin 4 to ground.