Application of CSP to the specification description, analysis and software design of elevator control systems and the implementation in Ada

CSP (communicating sequential processes) is a useful theory applicable to many fields of sequence control. This paper studies the specification description and analysis of elevator control systems in CSP, designs a methodology to find adequate software module structures of the systems in CSP and reports on the implementation of the systems in Ada for the confirmation of the study. The study clarifies general movements of the systems including deadlock problems and a method to find adequate software module structures of the systems in the cases with one car and with plural cars, by the techniques of process algebra, especially-process composition, interleave reduction of events and concealment of events.