μ-Charts and Z: examples and extensions

Abstract

p-Charts are a way of specifying reactive systems, i.e. systerns which are in some environment to which they have to react, based on the well-established formalism Statecharts. This paper gives (very abbreviated) examples of translating p-charts to Z, which is itself a well-established language for specifying computational systems with tried and tested methods and support tools which guide its effective use in systems development. We undertake this translation in order that investigation of the modelled system can be performed before expensive and lengthy implementation is considered. We also present an extension of the p-charts and the related Z to deal with a simple command language, local variables and integer-valued signals.

Idioms for μ-charts

“…p-Charts ("micro-charts,'), described in [6], [SI, [7], can be used to provide an abstract model of reactive systemsabstract because the models assume properties (such as instantaneity in transitions) that are unlikely to be present in implementations of the systems.…”

“…This allows us to use tools like ZEVES [lo] to prove properties of our p-chart-specified systems (e.g. [7]). Future research concems deriving, via the connection with Z and its own logic and rehement rules (e.g.…”