NXShield Library Reference by OpenElectrons.com
At the time of this writing, NXShield and this library can be used with following boards:
Mega 2560 or ADK
If you need help to begin with your first program, please download and review NXShield-AVR-Library-Tutorial.pdf from following url: http://www.openelectrons.com/index.php?module=documents&JAS_DocumentManager_op=viewDocument&JAS_Document_id=1
More information about NXShield is available at: http://www.openelectrons.com/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=7
Online documentation of this Library Reference is available at: http://www.openelectrons.com/NXShield/html/ (Note however, the online version may not match exactly with the library files you have installed on your computer).
To install this library in your Arduino IDE, download the latest zip file from following location: http://sourceforge.net/projects/nxshield/files/
And follow the instructions at that url to install it on your computer.