Nuts and Volts - June 2014

42 June 2014

BUILD IT YOURSELF

This easy-to-build-and-use tester will allow you to test any BASIC Stamp modules for bad I/O pins, RAM, and other issues that may cause problems in your projects. This tester only works on Stamps that can still communicate with a PC and cannot test modules that are completely dead (bricked).

A Little History

BASIC Stamps are one of the most well-known microcontrollers out there. That popularity is well deserved, and includes vast amounts of free documentation and example code, as well as free technical support. Parallax takes great pride in manufacturing these microcontrollers here in the USA, and every Stamp made is fully tested before being sold. This procedure is done one Stamp at a time, usually in lots of 50, 100, or more.

Over time, Parallax has developed and improved the testing of their modules. Originally, there were separate programs and test boards for each Stamp model. My goal as a tech guy at Parallax was to have one board and source code to handle everything.

To that end, I worked with Senior Application Engineer Jeff Martin to not only simplify the test procedure for manufacturing, but make it better and be able to detect more possible types of problems. While the code was being improved, I created a test board that could handle any Stamp module. This includes the BS1 and all 24- and 40-pin Stamp 2 models.