Real time system are in continual interaction with the execution environment. Due to their complex nature, such systems are extremely dif-ficult to specify and implement. The correctness of such systems depends on the time within the system responds to external events coming from the execution environment. Real time systems can be find in different areas like automotive, telecommunications, production techniques, plant control and avionics. The common feature of all real time systems is timeliness. However, this ostensibly simple property characterizes a vast spectrum of very different types of real time systems. There are two main classes of such systems: hard real time systems, which are consid-ered in this paper, are incorrect if their responses do not meet the specified deadline and soft real time systems, where response times are important, but the system will still function correctly if deadlines are occasionally missed. The most important stage in the development of any hard real time system is the generation of a consistent design that satisfies the specification of the requirements. The use of an appropriate design methodology that supports both the modelling of functional properties and non-func-tional properties (timeliness, dependability, reliability etc.) of a hard real time System is a crucial prerequisite for the successful design of such systems.
01 / 1999
11th EUROMICRO Conference on Real-Time Systems: Work in Progress Proceedings - York