This is a port of the code that is used to control the "Adafruit Bicolor LED Square Pixel Matrix" to C. Also functions to easily display characters on the LED matrix were added. You can find the original C++ code at https://github.com/adafruit/Adafruit-LED-Backpack-Library and the bicolor matrix at https://www.adafruit.com/products/902.
I used it to control a LED matrix with a Raspberry Pi.
ex_Bicolor_Matrix.c contains an example of how to use the functions to control the LED matrix. To run the code you may need to install the libi2c-dev package first.