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 Tracing a net 

Last post Mon, Feb 21 2011 2:25 AM by Andrew Beckett. 13 replies.
Started by J Wilwert 21 Jul 2010 08:53 AM. Topic has 13 replies and 3471 views
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  • Wed, Jul 21 2010 8:53 AM

    • J Wilwert
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    Tracing a net Reply

    Hi,

    I would like to trace a net through the layout heirarachy and then plot the traced net.  I have done this with a DIVA script, and would like to rewrite the script using assura.  Possible? I need a little help getting started as I am not well versed in using assura.  These traced net plots are very useful.   Many thanks in advance,

    John Wilwert 

    • Post Points: 20
  • Wed, Jul 21 2010 12:02 PM

    • dmay
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    Re: Tracing a net Reply

    If you are running Cadence 6.1.4 and the nets are not that big (not supply nets), then you can use Connectivity->Nets->Mark Net, and then use Connectivity->Nets->Save All Mark Nets  to save the results to a cell. You could then plot the new cell.

    Derek

    • Post Points: 20
  • Wed, Jul 21 2010 12:10 PM

    • J Wilwert
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    Re: Tracing a net Reply

    Hi Derek,

    I'd really like to say that I'm using Cadence 6.x!  Well, that is not exactly true.  Do you have any ideas on making this work in Cadence <6.x? (5.1.x)  THANKS!

    John Wilwert 

    • Post Points: 20
  • Wed, Jul 21 2010 12:39 PM

    • dmay
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    Re: Tracing a net Reply

    Actually, we are still using 5.1.41.x and don't know when we'll be on 6.1.x. I just happen to know about that particular feature and knew it would be easier than a new ruledeck for Assura. We use a third party verification tool to extract our supply nets for separate viewing/plotting. Unfortunately, I can't help you with Assura.

    Derek

    • Post Points: 20
  • Thu, Jul 22 2010 3:13 AM

    • Quek
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    Re: Tracing a net Reply

    Hi John

    Perhaps you can code something similar to:

    drcExtractRules(
       layerDefs( "df2"
          m1=layer("Metal1")
          m1Pins=textToPins("Metal1")
          ...
       ) ;layerDefs

       geomConnect(
          via( cont m1 poly psub ... )
          label( m1Pins m1 )
       ) ;geomConnect

       vddM1=geomGetNet(m1 "VDD")
       vddM2=geomGetNet(m2 "VDD")
       ...
       vddM8=geomGetNet(m8 "VDD")
    ) ;drcExtractRules

    Now open drc and set avParameters ?outputErrorLib to "Output Error Lib". In "View Additional Functions" secton of the drc form, please select "Create New Layout Database". In the outFile form, save lvs layer "vddM1" ... "vddM8" to the actual DFII layers. Now run drc. You will get a new library with the vdd net.

    Best regards
    Quek 

    • Post Points: 35
  • Thu, Jul 22 2010 6:23 AM

    • J Wilwert
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    Re: Tracing a net Reply

    Quek,

    Thanks for jumpimg in on this - I really appreciate the help.

    Everything looks good.  I am down to the part:

    In the outFile form, save lvs layer "vddM1" ... "vddM8" to the actual DFII layers.

    How (and where) do I do this?  I am stopped cold on this part.  Any thoughts?

    Again, THANK YOU!

    John Wilwert 

    • Post Points: 20
  • Thu, Jul 22 2010 6:37 AM

    • Quek
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    Re: Tracing a net Reply

    Hi John

    Here are the steps:

    In the outFile form, please do the following:
    a. Fill in the name of a new library
    b. Enter a path for the new libary
    c. Enter the name of the tech library
    d. For "Assura layer name", enter the name of the layer that appears in the rules file
    e. For "Layer name", enter the name of the layer that appears in LSW
    f. Add the layer to the text box
    g. Repeat for all other layers

    Please see the sample below. : )

    Best regards
    Quek


    • Post Points: 20
  • Thu, Jul 22 2010 6:55 AM

    • J Wilwert
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    Re: Tracing a net Reply

    Quek

    Thanks - So how do I get to this form?  Where can I find it?

    Also, I suspoect that this form writes or appends a file somewhere.   Maybe, I could just write or append the file.

    Thanks,

    John Wilwert 

    • Post Points: 20
  • Thu, Jul 22 2010 7:03 AM

    • Quek
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    Re: Tracing a net Reply

    Hi John

    At the end of the lvs form, please enable "View Additional Function". Then enable "Create New Database" option and press the button.


    Best regards
    Quek

    • Post Points: 20
  • Thu, Jul 22 2010 7:47 AM

    • J Wilwert
    • Top 200 Contributor
    • Joined on Tue, Jan 6 2009
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    Re: Tracing a net Reply

    Quek,

    Thanks - I found the form and followed it through.

     I guess I need to back up a little and clearify a point.  The net I need to plot may be any net a designer chooses.  So it may ot may not have a pin on it.  In the past, I've just placed an "X" on the net using the TEXT.drawing layer.  It think this slightly changes the code above.  Could you help me  get this coding correct?  Sorry for this oversight.

    Thanks,

    John Wilwert 

    • Post Points: 20
  • Thu, Jul 22 2010 7:49 AM

    • Quek
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    Re: Tracing a net Reply

    Hi John

    Please use this:

    layerDefs( "df2"
       myText=text("TEXT")
       ...
    )

    geomConnect(
       ...
       label(myText m1)
       ...
    )

    The above would create net labels instead of pin labels.

    Best regards
    Quek

    • Post Points: 20
  • Thu, Jul 22 2010 8:55 AM

    • J Wilwert
    • Top 200 Contributor
    • Joined on Tue, Jan 6 2009
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    Re: Tracing a net Answer Reply

    Quek,

    Cool !!!!  All is good !!

    I've checked the .rsf file and it looks like everything is there that I need to automate this!

    Thanks for all your help,

    John Wilwert 

    • Post Points: 5
  • Sun, Feb 20 2011 8:07 PM

    • Peter123
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    Re: Tracing a net Reply

    Hi Quek,

     

    The assura syntax look similar to DIVA syntax..

    So, can i use DIVA instead of assura to perform the task mentioned?

     BTW, does skill executes "drcExtractRules" ?

    or in other word, can i execute DIVA in skill using drcExtractRules ? 

    I'm currently executes DIVA in skill using ivDRC....

     

    Pls help...

     

    Thanks,

    P

    • Post Points: 20
  • Mon, Feb 21 2011 2:25 AM

    Re: Tracing a net Reply
    • Post Points: 5
Page 1 of 1 (14 items)
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Started by J Wilwert at 21 Jul 2010 08:53 AM. Topic has 13 replies.