7.4 Extensions, Variations, and Project-Specific Diagrams

The diagram sets considered so far, especially UML, are wide-ranging and comprehensive. However, for the development of real (and, in particular, embedded) systems, they aren't sufficient. It may be, for instance, that:

• Notation just isn't provided to show particular items or areas of concern.
• The diagram models provided are inadequate and need to be expanded or adapted.
• Diagrams must be provided to meet specific (for example, defense) standards that use quite a different notational method.

What follows is essentially a broad-brush look at the issue, giving some examples of extensions, variations, and project-specific diagrams. By definition, there cannot be a standard (in terms of semantics and syntax) for these, although common factors can certainly be identified.

(a) System Configuration Diagrams

In real-time embedded systems, it is necessary to show how computer hardware relates physically...