Error when trying Clock divider or multiplier circuit using sc_clock

[viswanathb]

My intention is to devise a clock multiplier or divider circuit based on a reference clock.

 

//CLOCK DUT
//clk_dut.h

#include "systemc.h"

SC_MODULE(clk_dut)
 {
  void gen()
  {
  double ref_clk =100;
  double clk1_div =10;
  double clk2_div=5;

sc_clock refclk("refclk",ref_clk,SC_NS);
sc_clock clk1("clk1",ref_clk/clk1_div,SC_NS);
sc_clock clk2("clk2",ref_clk/clk2_div,SC_NS);
  }
 SC_CTOR(clk_dut)
  {
   SC_THREAD(gen);
    sensitive << refclk.pos() << clk1.pos() << clk2.pos();
  }
};


//TOP MODULE

#include "systemc.h"
#include "clk_dut.h"

int sc_main(int argc,char *argv[])
 {
//instantiating the dut
clk_dut dut("dut");

dut.gen();

 sc_start(100,SC_NS);

return0;
  }
 

Error Message

 

clk_dut.h: In constructor ‘clk_dut::clk_dut(sc_core::sc_module_name)’:
clk_dut.h:18: error: ‘refclk’ was not declared in this scope
clk_dut.h:18: error: ‘clk1’ was not declared in this scope
clk_dut.h:18: error: ‘clk2’ was not declared in this scope
./sim: Command not found.
Please help me resolve this.

Also When i try to trace the clock files in the SC_THREAD after the sensitivity list using

 

sc_trace_file *fp;

fp=sc_create_vcd_trace_file("wave");

sc_trace(fp,refclk,"clk");

I get the same kind of scope error.

Please help me resolve this.

[apfitch]

You've declared your clock objects as member variables of an SC_THREAD, which is a bad idea - when the thread ends, the clocks disappear. Also your thread has no infinite loop, so it will end immediately.

The clock objects should be class members, something like this:

//CLOCK DUT
//clk_dut.h

#include "systemc.h"

SC_MODULE(clk_dut)
 {

  sc_clock refclk;
  sc_clock clk1;
  sc_clock clk2;


 SC_CTOR(clk_dut): refclk("refclk",100,SC_NS), 
                   clk1("clk1",10,SC_NS),
                   clk2("clk2",5,SC_NS)
  {

  }
};

If you want to declare them in a module, as you've shown, then you'll probably want to bind the clocks to some ports as well,

 

regards

Alan