...The build requires version 5.3.1 20160307 or newer of ARM GCC and will print an error message if the version is older than this. In order to turn your source code into binaries, you will need a tool called make. Windows users need to explicitly install make on their machines. Make sure you can use it from the terminal window. The entire Particle firmware is contained in this repository. The main user code sits in the application.cpp file under firmware/user/src/ folder. Unless you know what you are doing, refrain from making changes to any other files. ...