Design document aids support
Taniza Afrin, Hughes Network Systems, Germantown, MD -- Test & Measurement World, 10/1/2003
An effective software development project results in reliable, user-friendly, and bug-free code. To ensure that you create such code, you should take time to follow these steps:
- understand the customer's requirements;
- identify the common tasks to be performed repetitively;
- create a software flow diagram or class diagram;
- design user-interface and error-handling routines; and
- debug, test, and verify your software.
As you perform these steps, be sure to create what I call a software design document (SDD). Software maintenance will continue years after your project is complete, and support personnel—or you yourself—can look to the SDD throughout the program's life cycle. The SDD should explain the functions of the software's modules and how the modules work, and it should map global modules and variables in a traceable matrix.
An SDD proved invaluable to me when I was measuring power-detector accuracy during a test at both room and extreme temperatures using LabView. After several days of successful tester operation, the test data started showing anomalies. Relying on a bug traceability matrix in my SDD, I learned that the early successful measurements occurred at room temperature, while the problems occurred at hot temperatures. That knowledge pointed me directly to my LabView sequence designated "Hot," where I could quickly fix the bug.
To learn the details of how to implement the process that has helped me develop effective test programs in various languages, see www.tmworld.com/software_rules.
