Connecting Buttons to Feather
Going back to the Button PCB, we can get it ready to connect to the Adafruit Feather. Before soldering, I suggest slipping on a piece of heat shrink tubing to keep the wires grouped together.
Solder Button Wires to Feather
The buttons will need to be connected to the analog pins on the Adafruit Feather. Solder the wires to pins A5, A4, A3 and A2 – Doesn't matter which order the buttons go as along as they are connected to those analog pins. Connect the ground wire to any of the available ground pins on the Adafruit Feather.