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  3. forcing the creation of a vcd file

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forcing the creation of a vcd file

freitas
freitas over 13 years ago

Hello,

How do I instruct simvision to force the creation of a vcd file?

I am trying to create tcl script to dump signals into a vcd file and then immediately post-process this very vcd.

These are the two lines I want to run in sequence from a ncsim tcl script : 

simvision -submit "database export $my_signals -format vcd -name my_vcd.vcd"

file copy my_vcd.vcd ${my_dir}/myvcd.vcd

The problem that I am experiencing is that simvision seems to postpone the creation of the vcd file. Therefore, at the moment the second line is executed the vcd file is not yet available.

I get the following error:

ncsim> *E,TCLERR: error copying "driver.vcd": no such file or directory

However, if I run the two lines separately (i.e., not in a script) it works.So It seems that I have to force the creation of the vcd, but I don't know how.

I would appreciate your help.

Thanks!

 

 

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  • StephenH
    StephenH over 12 years ago

    Hi Sumeet.

    The VCD format itself doesn't support complex types like structs, which is why ncsim is telling you it cannot probe the object. As an aside, you may want to try the command "nchelp ncsim DBOBBD" at your Linux prompt to see a detailed explanation of the error message.

    Unless you absolutely require VCD format you'd do better to use the native SHM format because it supports structs, classes and other types that VCD cannot. In addition it's faster than VCD and takes a lot less disk space...

     

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  • StephenH
    StephenH over 12 years ago

    Hi Sumeet.

    The VCD format itself doesn't support complex types like structs, which is why ncsim is telling you it cannot probe the object. As an aside, you may want to try the command "nchelp ncsim DBOBBD" at your Linux prompt to see a detailed explanation of the error message.

    Unless you absolutely require VCD format you'd do better to use the native SHM format because it supports structs, classes and other types that VCD cannot. In addition it's faster than VCD and takes a lot less disk space...

     

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