Gerard Berry

(Esterel Technologies)

"The evolution of the synchronous programming model"

(Vortrag im Rahmen der "Distinguished Lecture Series" des Max Planck Instituts für Software-Systeme)

The synchronous programming model has become a major model in industrial embedded systems design (avionics, railways, SoCs, etc.) because it reconciles concurrency and determinism. For hardware systems, synchrony naturally fits the RTL paradigm and makes it fully rigorous. For software systems,synchrony naturally fits with two classical engineering models informally based on cyclic computations: data-flow block diagrams and control-flow state machines. The initial synchronous languages were dedicated either to data-flow designs (Lustre, Signal, etc.) or to control-oriented designs (Esterel, SyncCharts, etc.). The more recent languages completely unify both point of views: Esterel v7 keeps all the temporal primitives of the initial Esterel language and adds poweful datapath definition mechanisms, while Scade 6 provides its user with an graphical merge of data-flow diagrams and hierarchical state machines. We present the principles of these recent unifications, which are non-trivial: while it is quit easy to merge the drawing styles, it is much harder to do so by respecting the semantic properties of the languages. We show how the new languages simplify application design, and how they also provide formal verification systems with vital static information. We finally discuss new proposals to extend the original synchronous model into mixed synchronous / asynchronous that try to keep non-determinism under control.

Zeit:	Mittwoch, 29. Oktober 2008, 16:00 Uhr
Ort:	Gebäude 49, Raum 204-206
Hinweis:	Der Vortrag wird live an die Universität des Saarlandes MPI-Gebäude E1.4 Raum 019 übertragen.