High-Level-Net Semantics of a Real-Time Prototyping Language

摘要

The denotational semantics of the Prototype System Description Language (PSDL) isformally described in terms of an algebra-based Petri net model in the paper. PSDL supports specification and design of software prototypes that have to satisfy hard real-time constraints. The language is derived from a dataflow model that is augmented by data abstraction facilities and application-oriented timing and control constraints. In the Petri net model, each net is associated with a many-sorted partial algebra and is labeled with terms and marked with data of that algebra. The algebra serves to interpret the built-in and user-defined data types and functions of a specification, while the net defines a partial order semantics of its dynamic behavior. To capture the semantics of timing constraints in PSDL, they constrain transitions by conditions depending on time values of abstract clocks modeling the local time of distributed computational resources. (Copyright (c) GMD 1991.)