A function is a certain requirement or characteristic of the overall system that can be realized by hardware and/or software. A function is also however the solution to a control, regulation or display task. Such functions can also be termed application functions (compare Application functions).
Figure 16: Application functions
The functions realized in the software are described in <sw-function-spec>. These functions are classified according to classes (<sw-function-class>). The description for the functions can be variant-specific. A minimum of one function variant must exist for each function (<sw-function-variant>).
Figure 17: Function specification