This is my first attempt at an Arduino Oscilloscope with Processing. Still incomplete; but basically does the job of plotting and recording 3 analog signals connected to 3 Arduino inputs. Controlling the H-sweep has been the hardest part of the project for me. It has severe limitations regarding frequency response; but I want it mainly for very low frequency signals, such as temp, relative humidity, pressure, etc. At this point it has 3 simple pots connected as voltage dividers to the Arduino inputs to vary the voltage and observe the variations. Still a long way to go to finish it; but I can use it already.
here is the video: http://www.youtube.com/watch?v=14wGzvVhpnc