i have an old usb joystick that i tore apart for use with my microcontroller, and ive tried a couple different things to solve the problem of the pots not reaching their extremes (being configured as a voltage divider [5v power], they were within about 1v min and 3v max). any software compensation reduced the resolution, so i tried using positive and negative voltage regulators (317's and 337's) to bias them, but they were somewhat unreliable and required a dual supply. im rather stumped on the subject. any ideas?