i do believe that innovation first has that at their web site. i know that my fellow programmer didn't like their version, so he made up his own, but i'm not exactly sure how it works. i suggest going to
http://www.innovationfirst.com/firstrobotics and clicking on the white papers, then go to the joystick filter code. cut and paste the code, and alter the variables to what you need. that's the best help i can give you.