Static timing analysis of real-time systems

Abstract

The approach we propose consists in describing a real-time system with a timed extension of a synchronous language. The formal semantics of the language describes how programs can be translated into a wide class of models, usually labeled transition systems, but whose labels can range from pure boolean information to complex assignements to real-valued variables. In particular, Timed Graphs [ACD90] may be obtained. We then use a tool which implements a symbolic modelchecking algorithm for TCTL [ACD90] properties of Timed Graphs. We illustrate the approach with an example taken from robotics. Several real-time tasks are involved in a synchronization scheme, sending and receiving messages, according to various protocols. They are periodically re-activated by an external controller, and should not be re-activated if they are still communicating with each other. We show how to statically determine whether a particular choice of the re-activation delays would allow a deadlock.