Performance Modeling and Analysis Using VHDL and System:Shared Bus Model

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Shared Bus Model

The shared bus architecture consists of a single logical communication medium, which is an object of class comm_medium. The behavior is encapsulated in the shared_bus_io class. This class inherits the virtual interface functions from the my_basic_rw_port class, and must provide an implementation for them. The implementation for these functions is shown in Figure 77.48. The functions essentially map the interface functions to the methods of the comm_medium object. The data_to_delay function takes the data_size passed to the read method, and calculates the required transaction time in nanoseconds based on the bandwidth, and then adds the fixed communication overhead that the channel’s constructor reads in from the channel parameter file.

Performance Modeling and Analysis Using VHDL and SystemC-0104

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