Page 170 - DCAP405_SOFTWARE_ENGINEERING

Unit 9: System Engineering

The interfaces are generated by composing elements from the CODIS library. These elements Notes
implement the layers in Figure. They may be customized in terms of number of ports and their
data type. The interfaces for DM are automatically generated by a script generator that has as
input user defined parameters. The model is compiled and the link editor calls the library from
SystemC and a static library called “simulation library” (see Figure 9.14). The interfaces for
Simulink are functional blocks programmed in C++ using S-Functions. These blocks are
manipulated like all other components of the Simulink library. The user starts by dragging the
interfaces from the library into the model’s window, then parameterizes them and finally
connects them to the model inputs and outputs. Before the simulation, the functionalities
of these blocks are loaded by Simulink from the “.dll” dynamically linked libraries.

Experimental Results

To evaluate the performances of simulation models generated in CODIS, we measured the
overhead given by the simulation interfaces. The overhead caused by the Simulink integration
step adjustment when detecting a SystemC event has been measured in a maximum of 10% of
total simulation time. The overhead caused by IPC (Inter Process Communication) used for the
context switch and the communication layers has been measured in order of maximum 20% of
the total simulation time. The cost of the added synchronization functionality in the case of
SystemC is negligible and does not exceed 0.02% of the total simulation time.

Tasks
1. What was the name of the primarily tool which use as the solution of differential
equations system?
2. What is the role of modelling and simulation?

Self Assessment

Fill in the blanks:
11. The correct formulation of a …………………… can be a challenging task and its correctness
is essential to the quality of the results flowing from the modeling and simulation project.
12. The …………………………… layer is in charge of sending/receiving data between CM
and DM.
13. In discrete models, processes are sensitive to events while in continuous models processes
are executed at each ………………….. step.

14. In the modelling and simulation literature, the phrase ‘………………………..’ is frequently
reduced simply to ‘model’.
15. A data requirement here could be a single ……………….. value representing the coefficient
of friction associated with the flow.

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