Process level test generation for VHDL behavioral models

Abstract

This thesis describes the development of the Process Test Generation (PTG) software for the testing of single-process VHDL behavioral models. The PTG software, along with Hierarchical Behavioral Test Generator (HBTG) and Modeler's Assistant, forms a part of the Automatic Test Generation System being developed at Virginia Tech. The PTG software transforms the VHDL description of a circuit, given by Modeler's Assistant, into a Control Flow Graph (CFG) that describes the control and data flow information in the behavioral model. The process test generation algorithm, called the PTG algorithm, uses the CFG to generate stimulus/response test sets that test all the functions of the VHDL model. The algorithm creates events on signals, propagates these events and uses simulation to obtain responses. Various features present in the software like the generation of the Control Flow Graph, the PTG algorithm, and the construction of paths through the CFG to propagate and justify events, are discussed. The test sets generated by PTG can be used for the hierarchical test generation by HBTG, which was developed earlier. Another program, called Test Bench Generator (TBG), is presented in this thesis. It is used to convert the test sequence generated by HBTG into a VHDL Test Bench that can be used for simulation.