https://www.klipper3d.org/RPi_microcontroller.html
cd ~/klipper/
sudo cp "./scripts/klipper-mcu-start.sh" /etc/init.d/klipper_mcu
sudo update-rc.d klipper_mcu defaults
cd ~/klipper/
make menuconfig
- Micro-controller Architecture --> Linux process
- q --> yes
sudo service klipper stop
make flash
sudo service klipper start
sudo raspi-config
- Interface Options --> SPI --> enable