If you have ever wondered how much time you have used on a project, Mark Wilson has the project for you - his Pr0JCL0C. It is a simple timer and clock that will record elapsed time between pressing a start and finish button - ideal for logging total time spent on a particular project. It is simple to build, and only uses an Arduino board, a real-time clock and display. Here it is in operation:
Simple, yet effective. For more information, including detailed photos, circuit and the Arduino sketch - see Mark's page. If you are building your own project clock - consider using one of our Arduino-compatibles such as the Freetronics Eleven, and our highly accurate real-time clock module: