This software allows you to get a visual representation of an analog signal using Arduino and Processing. The resolution is 10 bits so this is not like a real oscilloscope but it is still pretty useful. It works by sending values read from the Arduino board (pin 0) to Processing through serial communication.
Although i would recomend getting a real oscilloscope because it works better and has better resolution, this project could also be usefull when you don’t have an oscilloscope around and you’re in need of one. Also you could build it to experiment and have fun.
Arduino Oscilloscope: [Link]