Analysis of an Ada system using coloured Petri nets and occurrence graphs

Abstract

This paper summarizes a project that used a new prototype occurrence graph (OG) tool to analyze a hierarchical coloured Petri net. The net models the behavior of an example Ada program that controls an interrupt-driven system. Our goals were to verify the results of the prior manual analysis, further examine the Ada program design, and assess the significance of such tool support in the application of Petri net theory to Ada program development. With OG tool support, we were able to identify additional problems with this Ada program that had defied manual analysis. The new insights gained with minimal effort are very encouraging. We believe the approach we have demonstrated can, with further refinements, become a practical means of verifying Ada program designs.