Not getting correct result with sc_time_stamp()

[Monc]

I am trying to print the simulation advanced in the units of attosecond, zeptosecond and yoctosecond, but I am getting 0 second in the print messages. It seems like the simulation timing is round off to second and since the number is small it is printing as 0 second. Can someone guide me how to print the actual timing ?

std::cout << "Time: " << sc_time_stamp() << std::endl; // 
wait(10, SC_AS); // attosecond
std::cout << "Time: " << sc_time_stamp()<< std::endl;
wait(10, SC_US); // zeptosecond
std::cout << "Time: " << sc_simulation_time() << std::endl;
wait(10, SC_YS); // yoctosecond
std::cout << "Time: " << sc_simulation_time() << std::endl;

 

 

Output: 

 

Time: 0 s
Time: 0 s
Time: 0 s
Time: 0 s

 

[Andy Goodrich]

You need to set the time resolution down to yoctoseconds: 

sc_set_time_resolution(1.0, SC_YS);

This call needs to be done before any sc_time instance would be generated, e.g., at the top of your sc_main().

The example below yields:

        SystemC 3.0.0-Accellera --- Jun 25 2024 13:14:11

        Copyright (c) 1996-2024 by all Contributors,

        ALL RIGHTS RESERVED

Time initially: 0 s

Time after SC_AS wait: 10 as

Time after SC_ZS wait: 10010 zs

Time after SC_YS wait: 10010010 ys

 

Info: /OSCI/SystemC: Simulation stopped by user.

Program completed

The example:

SC_MODULE(DUT)

{

    SC_CTOR(DUT)

    {   

        SC_THREAD(thread);

    }

    void thread()

    {   

        std::cout << "Time initially: " << sc_time_stamp() << std::endl; //

        wait(10, SC_AS); // attosecond

        std::cout << "Time after SC_AS wait: " << sc_time_stamp()<< std::endl;

        wait(10, SC_ZS); // zeptosecond

        std::cout << "Time after SC_ZS wait: " << sc_time_stamp() << std::endl;

        wait(10, SC_YS); // yoctosecond

        std::cout << "Time after SC_YS wait: " << sc_time_stamp() << std::endl;

        sc_stop();

    }

    sc_in<bool> m_clk;

};

 

int sc_main(int argc, char* argv[])

{

    sc_set_time_resolution(1.0, SC_YS);

    sc_clock        clock("clock");

    DUT             dut("dut");

 

    dut.m_clk(clock);

    sc_start();

 

    cout << "Program completed" << endl;

    return 0;

}

 

 

[Monc]

Thank you very much !

This is exactly what I was looking for.