Code to Arduino UNO and MEGA.
INSTALATION Just install POT in each analog port. Using the _Grnd _Analog _5V Arduino. Like this image: http://arduino.cc/en/uploads/Tutorial/joy_sch_480.jpg
To setup the buttons, just install you prefered button switch under GND and Port Digital 02~13. Use Flip to erease and burn this firmware DFU: https://github.com/harlequin-tech/arduino-usb/blob/master/firmwares/Arduino-big-joystick.hex I used Arduino R3 with Atmega 16U2.
To watch a demonstrate video: http://youtu.be/JMYjVJvOTX8