Deterministic Replay Debugging of IEC 61131-3 SoftPLC Programs
Sprache des Titels:
Industrial Informatics (INDIN), 2010 8th IEEE International Conference on Industrial Informatics
Determimstic Replay Debugging is an approach to finding field failures in application runs. It records an application run so that it can be replayed deterministically in a development system for debugging purposes without connection to a physical environment. In this paper, we present a solution for deterministic replay debugging of hard real-time SoftPLC applications written in the IEC 61131-3 languages. By taking advantage of the special properties of these programs and by careful engineering, our technique allows recording a SoftPLC application run with minimal overhead and obeying real-time constraints. In later phases, which are off-line, the original program run is reconstructed to be replayed for debugging. We present the conceptual basis of our approach, a tool chain including a time-traveling debugger, and an evaluation as well as an industrial case study for validating the approach.