Specification of Reactive Hardware/Software Systems - Electronic ...

374 SHE Framework
11.5.6 Extended Unified Model
Extension of the behaviour description is prepared by the extensions of the Message
Flow Diagrams with their scenario narratives, Object Class Diagrams, Instance Structure
Diagrams and the old Essential Unified Model. A lot of complex design problems must
be tackled in the extended modelling phase. Allocation and scheduling problems and
the assignment of priority schemes must be dealt with. This can only be done considered
when performance can be estimated. Therefore the integration of adequate modelling
of performance will be a major issue for our future research.
11.6 Concluding Remarks
In this chapter we described the framework of the method Hardware/Software Engineering.
This method is based on the concepts described in the former chapters. The
method enables the specification, modelling and exploration of a system or product to
be designed. Besides an inventory of functionality and data in an object based way the
method yields a well thought-out system level structure and a refined description of
dynamic behaviour in an executable model. The modelling process integrates analysis
of essential aspects and implementation aspects in a considered way. This chapter gives
only a brief overview of the method and its heuristics. For practical use of the method
we must develop an extensive textbook with a focus on guidelines and heuristics based
on practical examples. The method is applied in an industrial case which is presented
in the next chapter.