This page describes an experiment in using PyMata Express to communicate (using Firmata) between a Raspberry Pi and an ItsyBitsy microcontroller.
Installing PyMata Express on Linux/Raspberry Pi#
To install Pymata Express on Linux (including Raspberry Pi) and macOS computers, open a terminal window and type:
sudo pip3 install pymata-express
Installing Firmata Express on an Arduino#
https://mryslab.github.io/pymata-express/firmata_express/