Building
--------
Get the CircuitPython repo.
git clone https://github.com/adafruit/circuitpython.git

Patch CircuitPython.
TODO: supervisor/shared/usb/usb_desc.c supervisor/usb.h
copy board file.
cp -r geekabit_adapter circuitpython/ports/raspberrypi/boards/

Build it using this excellent guide.
https://learn.adafruit.com/building-circuitpython/build-circuitpython

I had to manually install huffman in order to compile mpy_cross.
pip3 install --upgrade huffman

Copy firmware.
cp circuitpython/ports/raspberrypi/build-geekabit_adapter/firmware.uf2 .


Installation
------------
- Hold down the BOOTSEL button on the Raspberry Pi Pico.
- Plug the Pico into a USB port on your computer.
- The Pico will appear as a USB mass storage device named "RPI-RP2".
- Copy the file firmware.uf2 to the RPI-RP2 drive.
- After copying, the Pico will reboot automatically.
- The Pico will appear as a USB mass storage device named "CIRCUITPY".
- Copy boot.py and code.py to the CIRCUITPY drive.
- Unplug and re-plug the Pico.

After this, the adapter should appear as a USB HID device compatible with the
EVBox ChargeStation Tool.
