The DDC101 Evaluation Fixture is a modular design. With the use of the common DDC101 Evaluation Fixture PC Interface Board, different Device Under Test (DUT) Boards may be used. Different DUT boards can be used to evaluate single or up to 32 DDC101s in any package type. Design of the DUT boards and their use are detailed in the DDC101 Evaluation Fixture product data sheet. This application note focuses on how to communicate directly to the PC Interface Board through a PC’s printer port. This communication is used to configure the PC Interface Board as well as to configure and retrieve data from the DDC101s on the DUT Board. This will allow the user to write custom software to create user specific, extended capabilities not available in the standard program. The software for the DDC101 Evaluation Board was written in Turbo Pascal®. The code can be readily modified to be used with other languages. All software examples listed use Turbo Pascal syntax.