Patrick Cambria posts this simple oscilloscope project using a Picaxe-08M microcontroller and a potentiometer. The Picaxe is programmed in BASIC and the entire MCU program follows:
The output from a potentiometer voltage divider is fed into an ADC pin of a PICAXE 08M then serially transmitted to a Serial Port in Visual Basic.NET and plotted over time in a line graph. (Patrick also notes you can also use a bar graph for a nice visual effect!)
For links to the schematic and Visual Studio source code visit Patrick Cambria’s website.