A Yourdon-based state transition logic approach to software design and implementation

The author illustrates how Yourdon techniques can be used (and enhanced) to design and implement a software system. The use of state transition logic (STL) diagrams and Fortran examples are presented (although the method applies equally to other high-order languages, such as Cobol and Ada). The standard Yourdon design methodology is enhanced by using scheduled events. In the present simulation and in many other applications, there is a need to execute functions on the basis of future actions that are the outcome of existing events. A scheduling routine is used to keep track of each execution time requirement. As the function execution requirement is met, an action is triggered. This action puts the system in the desired state