Development tools
From FlySight
At the heart of FlySight is an AT90USB microcontroller. The datasheet for the AT90USB family can be found here:
https://www.atmel.com/dyn/resources/prod_documents/doc7593.pdf
The firmware is written in C, and can be compiled using AVR-GCC. If you're using Windows, the tool of choice is WinAVR:
https://winavr.sourceforge.net/
WinAVR includes a simple editor called Programmer's Notepad, which makes it easy to compile the source. Once it's compiled, you'll need to program the FlySight itself. This is described in further detail here.
