Dr. Jon Valvano is a professor in the Department of Electrical and Computer Engineering at The University of Texas at Austin. Along with senior lecturer Ramesh Yerraballi, they teach the very popular EdX course – Embedded Systems – Shape The World .

The LM4F120/TM4C123 LaunchPads are one of the go to development kits for their embedded courses. A course would mean alot of kits in the hands of students. He came up with an automated self diagnostic tool which when coupled with a test BoosterPack, any broken I/O ports are listed out.

The below quote explains how the test BoosterPack works:

To test each digital GPIO pin, the software running on the Stellaris LaunchPad configures one pin on each GPIO port as an output and the rest of the pins on the GPIO port as inputs. It attempts to make each output high and low and checks that each input responds accordingly. Experience has indicated that GPIO pins can be broken in several ways: stuck high, stuck low, or broken input. The software attempts to check each case. When a measurement does not match expectation, an error message is printed through the UART to a computer running a terminal.

Schematics and software are available on Dr. Valvano’s page. Make sure you check out his courses and this awesome picture of him with a horse. That braid rocks!