ERTL: an extension to RTL for the specification, analysis and verification of hybrid systems

Real time logic (RTL) was introduced as a formalism for reasoning about the relative and absolute timing properties of computational tasks of discrete real-time systems. Extended real time logic (ERTL) is a formalism for the modelling and analysis of relative and absolute timing properties of hybrid systems (systems that combine continuous variables and discrete event dynamics). The extensions provided by ERTL enable the modelling of system behaviour ranging from activities of the physical entities that form part of the environment of a computing system, to the temporal ordering of the computational tasks of the computing system itself thus providing a formal notation that can be used in all stages of software development