A Graphical Environment for the Design of Concurrent Real-Time Systems

Concurrent real-time systems are among the most difficult systems to design because of the many possible interleavings of events and because of the timing requirements that must be satisfied. We have developed a graphical environment based on Real-Time Graphical Interval Logic (RTGIL) for specifying and reasoning about the designs of concurrent real-time systems. Specifications in the logic have an intuitive graphical representation that resembles the timing diagrams drawn by software and hardware engineers, with real-time constraints that bound the durations of intervals. The syntax-directed editor of the RTGIL environment enables the user to compose and edit graphical formulas on a workstation display; the automated theorem prover mechanically checks the validity of proofs in the logic; and the database and proof manager tracks proof dependencies and allows formulas to be stored and retrieved. This article describes the logic, methodology, and tools that comprise the prototyp