Jump to content

SystemC vcd trace file cannot display the waveform


krishna

Recommended Posts

Hi All,

 I am starting the practical implementation of systemc code for 4 bit counter using d flip flop. It works properly as it is, But the problem is with the vcd trace file. The main module produces a vcd file of type .vcd format but when i tried to open it in the gtkwave viewer, the vcd file cannot be opened. There is no error message also for debugging the problem.

My systemc code is given below

//dff.cpp
 
#include <systemc.h>
 
SC_MODULE (dff) {
    sc_in <bool> clk;
    sc_in <bool> din;
    sc_out <bool> dout,;
 
    void dff_method()
    {
     	dout=din;
    }
    
    SC_CTOR (dff) {
        SC_METHOD (dff_method);
            sensitive_pos << clk;
    }
}
//main.cpp
 
#include <systemc.h>
#include "dff.cpp"
 
int sc_main(int argc, char* argv[])
{
sc_core::sc_report_handler::set_actions( "/IEEE_Std_1666/deprecated",
                                           sc_core::SC_DO_NOTHING );
sc_set_time_resolution(100, SC_PS);
sc_signal<bool> din1, dout1;
sc_signal<bool> din2, dout2;
sc_signal<bool> din3, dout3;
sc_signal<bool> din4, dout4;
sc_signal<bool> en;
sc_signal<bool> clk;
 
int i;
    
dff dff1("dff");
dff1.din(din1);
dff1.dout(dout1);
dff1.clk(clk);
 
dff dff2("dff");
dff2.din(din2);
dff2.dout(dout2);
dff2.clk(clk);
 
dff dff3("dff");
dff3.din(din3);
dff3.dout(dout3);
dff3.clk(clk);
 
dff dff4("dff");
dff4.din(din4);
dff4.dout(dout4);
dff4.clk(clk);
 
sc_trace_file *fp;                    // VCD file
fp=sc_create_vcd_trace_file("wave");
sc_trace(fp,clk,"clk");               // signals
sc_trace(fp,din1,"en");
sc_trace(fp,dout1,"dout_one");
sc_trace(fp,dout2,"dout_two");
sc_trace(fp,dout3,"dout_three");
sc_trace(fp,dout4,"dout_four");
en=1;
for(i=0;i<40;i++)
{
din1=en^dout1;
din2=((en&dout1)^dout2);
din3=(((en&dout1)&dout2)^dout3);
din4=((((en&dout1)&dout2)&dout3)^dout4);
clk=0;
sc_start(1, SC_NS);
clk=1;
sc_start(1, SC_NS);
cout<<" @ "<<sc_time_stamp()<<" dout: "<<dout4<<dout3<<dout2<<dout1<<endl;
}   
sc_close_vcd_trace_file(fp);
return 0;
}

and the vcd file is shown as below when opened in vi editior:

$date
     Oct 13, 2014       21:46:55
$end
 
$version
 SystemC 2.3.1-Accellera --- Oct  8 2014 22:37:31
$end
 
$timescale
     100 ps
$end
 
$scope module SystemC $end
$var wire    1  aaaaa  clk       $end
$var wire    1  aaaab  en       $end
$var wire    1  aaaac  dout_one       $end
$var wire    1  aaaad  dout_two       $end
$var wire    1  aaaae  dout_three       $end
$var wire    1  aaaaf  dout_four       $end
$upscope $end
$enddefinitions  $end
 
$comment
All initial values are dumped below at time 0 sec = 0 timescale units.
$end
 
$dumpvars
0aaaaa
0aaaab
0aaaac
0aaaad
0aaaae
0aaaaf
$end
 
#10
1aaaaa
 
#20
0aaaaa
1aaaab
 
#30
1aaaaa
1aaaac
 
#40
0aaaaa
0aaaab
 
#50
1aaaaa
0aaaac
1aaaad
 
#60
0aaaaa
1aaaab
 
#70
1aaaaa
1aaaac
 
#80
0aaaaa
0aaaab
 
#90
1aaaaa
0aaaac
0aaaad
1aaaae
 
#100
0aaaaa
1aaaab
 
#110
1aaaaa
1aaaac
 
#120
0aaaaa
0aaaab
 
#130
1aaaaa
0aaaac
1aaaad
 
#140
0aaaaa
1aaaab
 
#150
1aaaaa
1aaaac
 
#160
0aaaaa
0aaaab
 
#170
1aaaaa
0aaaac
0aaaad
0aaaae
1aaaaf
 
#180
0aaaaa
1aaaab
 
#190
1aaaaa
1aaaac
 
#200
0aaaaa
0aaaab
 
#210
1aaaaa
0aaaac
1aaaad
 
#220
0aaaaa
1aaaab
 
#230
1aaaaa
1aaaac
 
#240
0aaaaa
0aaaab
 
#250
1aaaaa
0aaaac
0aaaad
1aaaae
 
#260
0aaaaa
1aaaab
 
#270
1aaaaa
1aaaac
 
#280
0aaaaa
0aaaab
 
#290
1aaaaa
0aaaac
1aaaad
 
#300
0aaaaa
1aaaab
 
#310
1aaaaa
1aaaac
 
#320
0aaaaa
0aaaab
 
#330
1aaaaa
0aaaac
0aaaad
0aaaae
0aaaaf
 
#340
0aaaaa
1aaaab
 
#350
1aaaaa
1aaaac
 
#360
0aaaaa
0aaaab
 
#370
1aaaaa
0aaaac
1aaaad
 
#380
0aaaaa
1aaaab
 
#390
1aaaaa
1aaaac
 
#400
0aaaaa
0aaaab
 
#410
1aaaaa
0aaaac
0aaaad
1aaaae
 
#420
0aaaaa
1aaaab
 
#430
1aaaaa
1aaaac
 
#440
0aaaaa
0aaaab
 
#450
1aaaaa
0aaaac
1aaaad
 
#460
0aaaaa
1aaaab
 
#470
1aaaaa
1aaaac
 
#480
0aaaaa
0aaaab
 
#490
1aaaaa
0aaaac
0aaaad
0aaaae
1aaaaf
 
#500
0aaaaa
1aaaab
 
#510
1aaaaa
1aaaac
 
#520
0aaaaa
0aaaab
 
#530
1aaaaa
0aaaac
1aaaad
 
#540
0aaaaa
1aaaab
 
#550
1aaaaa
1aaaac
 
#560
0aaaaa
0aaaab
 
#570
1aaaaa
0aaaac
0aaaad
1aaaae
 
#580
0aaaaa
1aaaab
 
#590
1aaaaa
1aaaac
 
#600
0aaaaa
0aaaab
 
#610
1aaaaa
0aaaac
1aaaad
 
#620
0aaaaa
1aaaab
 
#630
1aaaaa
1aaaac
 
#640
0aaaaa
0aaaab
 
#650
1aaaaa
0aaaac
0aaaad
0aaaae
0aaaaf
 
#660
0aaaaa
1aaaab
 
#670
1aaaaa
1aaaac
 
#680
0aaaaa
0aaaab
 
#690
1aaaaa
0aaaac
1aaaad
 
#700
0aaaaa
1aaaab
 
#710
1aaaaa
1aaaac
 
#720
0aaaaa
0aaaab
 
#730
1aaaaa
0aaaac
0aaaad
1aaaae
 
#740
0aaaaa
1aaaab
 
#750
1aaaaa
1aaaac
 
#760
0aaaaa
0aaaab
 
#770
1aaaaa
0aaaac
1aaaad
 
#780
0aaaaa
1aaaab
 
#790
1aaaaa
1aaaac

As you can see the comment in the tracefile

 

 

  1. $comment
  2. All initial values are dumped below at time 0 sec = 0 timescale units.
  3. $end

So is this the reason the vcd file cannot be opened? if yes, what changes do i need to do in the main module to get waveform?

 

 

Please help me how to proceed to the problem solution.

 

Thanks in advance.

 

Link to post
Share on other sites
SC_MODULE (dff) {
sc_in <bool> clk;sc_in <bool> din;sc_out <bool> dout,;
void dff_method()
{    dout=din;}
SC_CTOR (dff) {SC_METHOD (dff_method);sensitive_pos << clk;}};

Add the semi colon at the end. I compiled this code It works fine . In GTK-Wave you have to click on the System C icon below SST and then add all the signals which appear on the window below .

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...