You probably want to take a look at Firmata: http://firmata.org/wiki/Main_Page It basically does the wrapping for you, so you can control the Arduino from y

You probably want to take a look at Firmata: http://firmata.org/wiki/Main_Page It basically does the wrapping for you, so you can control the Arduino from your PC using software you're already familiar with: Python, MaxMSP, Processing, PD etc