1 . You can see that, starting with the general requirements, there are three
steps to model the system context. I ??™ ll explain each of these steps in detail in the
following sections.
2.3.1 Identify System Actors
Identifying system actors is shown in Table 2.6 .
Systems consist of several units that work more or less autonomously and,
together, form the entire system as a network of communicating units. Since the
single system is, in turn, part of a larger system, we speak of an embedded system.
Note that for my defi nition of embedding it doesn ??™ t really matter whether the single
system is a simple 8-bit processor or a complex aggregate, such as an automobile,
8 Or accordingly the class or composite structure diagram in UML. You can also use the use case
diagram instead of the class or block definition diagram.
2.3 Modeling the System Context
We will start early to create the design for these requirements to check the
feasibility, recognize possible risks, and find changes to requirements that may
be necessary. ??? Early ??? means as soon as we will have added the first bunch of
requirements.
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