The Argos Language: Graphical Representation of Automata and Description of Reactive Systems

We present the Argos graphical synchronous language for the description of reactive systems, and the Argonaute environment associated with it. Systems like communication protocols, real time process controllers or man/machine interfaces contain a reactive kernel. Its behaviour can be described in a convenient manner by an automaton , for formal validation purposes. But, in general, complex systems cannot be described directly as automata. The Statecharts [4,5] and Argos [7,8] are automata-based languages. The high level constructs of the language deal with states and transitions directly. A consequence of this choice is the graphical syntax, since the best representation of small automata is graphical. A consequence of this graphical syntax is the need for graphical constructs: the constructs of the language must allow the decomposition of a system into small parts that can be represented directly by automata, and they must be given a readable graphical syntax.