USB Joystick

What kind of signal/data does a joystick transfer to the computer? Can I decode it with an Arduino or any IC?

A USB joystick uses the Human Interface Device (HID) protocol over USB. With a USB Host Shield you should be able to receive these messages and act on them.

Hi, The typical simple "Analog" Joystick has two potentiometers that connect to analog inputs that output X and Y position, and one digital switch that goes to a digital input for push-down Z .

See: http://arduino-info.wikispaces.com/BrickStarterSet and click on the Joystick...

There is general information on connecting potentiometers to arduino, and there are two test software sketches including one that shows the Joystick motion data.

DISCLAIMER: Mentioned stuff from my own shop...