This document summarizes an oscilloscope application project for TinyOS. It describes: 1) How the mote senses and broadcasts data and the base station gets the data and plots it in real time using a Java application. 2) The implementation in OscilloscopeAppC.nc which includes components for sensing, timers, LEDs, and active messaging. 3) How to compile and run the application by setting the sensor board type and running the Java GUI after exporting the MOTECOM environment variable.