ASIC/FPGA Design and Verification Out Source Services

Exporting simvision TRN to VCD

1. In this page I will show how to convert simvision TRN wave data base to VCD.


2. The motivation is to minimize to use of "license consuming" CAD software.


3. The tests, which I run at work, are quite long. Some may run several hours. So I use GUI only for the first steps of program bring-up and switch to batch mode for the rest of the debug process.


4. While the test runs and after it completes, I need to inspect the results. One way is to analyze waves. I use the free GTK wave viewer wherever possible.


5. I noticed that when the NC simulator is instructed to generate waves, in VCD format, from the TCL file, the simulation is slowed down dramatically.


6. At the verilog test-bench I use:


initial begin
  $shm_open ("lli.shm", , , , 1900, 0); //incremental size of 1.9G
//$shm_probe(tb.dut.i_lo_proc_top.i_losl_top, "AMSC");//current and below
  $shm_probe(tb.dut.i_lo_proc_top.i_losl_top, "ASC");//current and below
  $shm_probe(tb, "A");
end

From tcl the data base can be split into incremental size by using the following command:
database -open waves -incsize 1900M


7. So I generate TRN. To convert to VCD during and after run, from the command line, I use the following script:

#!/bin/bash
#1 vcd output file
#2 trn input file
cad simvisdbutil -vcd -OUTPUT $1 -OVERWRITE $2


8. If you need only a few signals out of a TRN files, to keep your VCD small in size, do the following:


#!/bin/bash

simvisdbutil -vcd -OUTPUT gtk.vcd -OVERWRITE ncsim.shm/ncsim.trn \
-signal pm_tb.dut.arm_div8_clk \
-signal pm_tb.dut.arm_div8_clk \
-signal pm_tb.dut.chn2_e2_paddr \
-signal pm_tb.dut.chn2_e2_penable \
-signal pm_tb.dut.chn2_e2_pwrite \
-signal pm_tb.dut.chn2_e2_psel \
-signal pm_tb.dut.chn2_e2_pready \
-signal pm_tb.dut.chn2_e2_pwdata \
-signal pm_tb.dut.chn2_e2_prdata \
-signal pm_tb.dut.arm_div8_clk \
-signal pm_tb.dut.chn2_e1_paddr \
-signal pm_tb.dut.chn2_e1_penable \
-signal pm_tb.dut.chn2_e1_pwrite \
-signal pm_tb.dut.chn2_e1_psel \
-signal pm_tb.dut.chn2_e1_pready \
-signal pm_tb.dut.chn2_e1_pwdata \
-signal pm_tb.dut.chn2_e1_prdata \
-signal pm_tb.dut.arm_dcsu_clk_out \
-signal pm_tb.dut.core_dcsu_clk_out \
-signal pm_tb.dut.mddr_dcsu_clk_out \
-signal pm_tb.dut.sddr_dcsu_clk_out \
-signal pm_tb.dut.arm_dcsu_lock \
-signal pm_tb.dut.core_dcsu_lock \
-signal pm_tb.dut.mddr_dcsu_lock \
-signal pm_tb.dut.sddr_dcsu_lock

ls gtk.vcd && gzip gtk.vcd
ls gtk.vcd.gz && \mv -f gtk.vcd.gz ~/Junk

If you use VCS, you can convert VPD to VCD in this way:
vpd2vcd inter.vpd inter.vcd

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An extension to the example from cadance of producer consumer.