GPIO setup

Using Linux Device-Tree

For ring trigger it is necessary to configure a Key Stroke. This can be achived with configuring an gpio.

Copy the gpio.dts to /boot/overlay-user/gpio.dts and if you are using armbian execute

armbian-add-overlay /boot/overlay-user/gpio.dts

This will compile the dts file to a dtbo compiled one and will append the overlay to your `armbianEnv.txt