This directory contains the source code for the USB device firmware for this project. It uses the AVR Arduino core and can be built using PlatformIO.
If you need to change anything in the build configuration, you can do so in the file platformio.ini. Adding support for a different Atmega32U4-based board that is supported by PlatformIO should be as simple as adding a new [env:<NAME>] section and setting its board to the appropriate PlatformIO board type. If you need to override build_flags, though, make sure to include the -DUSB_VERSION=0x210 bit, as that setting will replace the previously set flags, not add to it.
See the PlatformIO docs for the full reference on the format of that file.
The source code should be buildable on any host that PlatformIO can run on. If you don't already have it installed, install the PlatformIO CLI tools by following the PlatformIO installation instructions. Make sure the pio command is in your PATH (see here if you need help with that).
To build all configured board variants:
pio runTo program the built firmware into an attached USB device:
pio run -v --target upload --environment <ENVIRONMENT> --upload-port <PORT>Where <ENVIRONMENT> is one of the board type specific build environments configured in platformio.ini and <PORT> is the device name of the USB serial port the device shows up as on your system, such as COM6 or /dev/ttyUSB0.
Or you could use the atmega32u4_upload.py script from this project. Run it with --help option for full usage details. You can find the built firmware files at .pio/build/<ENVIRONMENT>/firmware.hex relative to this directory.