Teensy Firmware

https://docs.platformio.org/en/latest/core/installation.html#system-requirements

On Raspberry PI

teensy_loader_cli

mkdir packages && cd packages
git clone git@github.com:PaulStoffregen/teensy_loader_cli.git
cd teensy_loader_cli
make
sudo cp teensy_loader_cli /usr/bin/

Platformio

pip install virtualenv
virtualenv -p python3 ~/.platformio/penv
source ~/.platformio/penv/bin/activate
pip install platformio
pio boards
cd project
pio project init --board teensy41
pio run --target upload