Thom (www.skewworks.com) has developed a package of cores and libraries called Pyxis OS, which adds some impressive functionality to interface with the Buttonpad, TouchShield Slide, as well as SD cards.
Each of the primary pieces of the OS has their own library. PyxisSD for uSD access, PyxisFAT for the EEPROM file system, PyxisPad for interfacing with the ...
ButtonPad, PyxisLCD for communicating with the LCD and Pyxis for the top-level management of all the pieces.
In order to use the PyxisTSS core, please make the following entry in your boards.txt file: