The state graph from Figure 7-3

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The state graph from Figure 7-3

 

In Table 7-1, the vector NeuesElement220 with the states on the vectorNeuesElement219is considered. In the column Z', the subsequent states of Zk are written in connection with the vectorNeuesElement218.

 

The task now is to generate input sequences that can be used to simulate the automaton. As described in detail NeuesElement217, possible input combinations arise.

 

 

 

 

Z1

 

Z2

 

Z3

 

Z4

 

E1

E2

E3

A1

A2

Z‘

A1

A2

Z‘

A1

A2

Z‘

A1

A2

Z‘

0

0

0

0

0

 

1

0

 

0

0

 

0

1

 

0

0

1

0

0

Z2

1

0

 

0

0

Z4

0

1

 

0

1

0

0

0

 

1

0

Z3

0

0

 

0

1

 

0

1

1

0

0

Z2

1

0

Z3

0

0

Z4

0

1

 

1

0

0

0

0

 

1

0

 

0

0

 

0

1

Z1

1

0

1

0

0

Z2

1

0

 

0

0

Z4

0

1

Z1

1

1

0

0

0

 

1

0

Z3

0

0

 

0

1

Z1

1

1

1

0

0

Z2

1

0

Z3

0

0

Z4

0

1

Z1

Table 8-5 Simulation table of the state graph

 

 

 

The input vector with the elements E1, E2 and E3 corresponds with each combination to a scenario in the control path.

At first glance, it is obvious that not every input vector provides a defined result. All states are passed through, but through multiple transitions, several input vectors can lead to a further switching of the states from one state. The representation of the output vectors shows a clear assignment of the outputs to the states. The transitions are carried out independently of the overall system state. A meaningful simulation cannot be found here.  Those input vectors which are not explicitly considered in the control algorithm cannot be interpreted in the model. This leads to the statement:

The model can only interpret inputs from the control path that were considered in the control algorithm during control design.

This statement leads to the conclusion that with regard to the software quality criteria functionality and reliability, the simulation has shown that these criteria are not fulfilled. Since not every input vector leads to a defined result and since the transitions are considered "fulfilled" several times. Thus, the informative value of the formal specification by the model is not satisfactory.