Abstract A specification theory combines notions of specifications and implementations with a satisfaction relation, a refinement relation, and a set of operators supporting stepwise design. We develop a specification framework for realtime systems using Timed I/O Automata as the specification formalism, with the semantics expressed in terms of Timed I/O Transition Systems. We provide constructs for refinement, consistency checking, logical and structural composition, and quotient of specifications-all indispensable ingredients of a compositional design methodology. The theory is implemented in the new tool Ecdar. We present symbolic versions of the algorithms used in Ecdar, and demonstrate the use of the tool using a small case study in compositional verification. This paper is an extended version of the work previously presented in [23, 24, 25] . The main additions are (1) a unified presentation, (2) a deeper link between the theory and the tool, (3) proofs of theorems, and (4) the description of case studies.
In REF timed specifications are studied in the setting of timed I/O transition systems (TIOTS).
Real-time specifications
International Journal on Software Tools for Technology Transfer
International Journal on Software Tools for Technology Transfer
Computer Science