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  3. comparission of two GDS

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comparission of two GDS

sailesh
sailesh over 15 years ago

 Hi Frn'z

       u can get me the logic for this,

I  have two layout, they has to be compared and difference has to be given. I have done till getting the shapes and their corresponding metal layers & coordinates.Iam not able move further

 

 

 

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  • Andrew Beckett
    Andrew Beckett over 15 years ago

    Hi Bernd,

    Why does it need to flatten both the layouts? 

    I wrote an app note on doing this in Diva years ago (it was for 4.3.4, so that shows how long ago it was), but I never updated it for  4.4 (let alone IC6) and I can't locate the app note any more (it was probably 14 years ago...). But I can't see why you need to flatten both layouts.

    If I remember rightly, I did something in Diva by the following flow (roughly):

    1. Place an instance of one  layout and flatten it
    2. Change the purpose of all the shapes to a different purpose (e.g. "xor") which I added to the tech file for this purpose (excuse the pun)
    3. Place the instance of the second layout (no need to flatten)
    4. Do an xor of each drawing layer against the same layer, but xor purpose

    With Assura, Dracula, PVS and Calibre it's easier because they directly support having two different databases, whereas with Diva  you only have a single database, which complicates matters slightly.

    I seem to remember my app note had some scripts to automate adding the purposes and building the rule deck, and then some SKILL to do the above steps - but it's not exactly difficult. If you're using one of the other physical verificatioiin tools, it's simpler still.

    Regards,

    Andrew.

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  • Andrew Beckett
    Andrew Beckett over 15 years ago

    Hi Bernd,

    Why does it need to flatten both the layouts? 

    I wrote an app note on doing this in Diva years ago (it was for 4.3.4, so that shows how long ago it was), but I never updated it for  4.4 (let alone IC6) and I can't locate the app note any more (it was probably 14 years ago...). But I can't see why you need to flatten both layouts.

    If I remember rightly, I did something in Diva by the following flow (roughly):

    1. Place an instance of one  layout and flatten it
    2. Change the purpose of all the shapes to a different purpose (e.g. "xor") which I added to the tech file for this purpose (excuse the pun)
    3. Place the instance of the second layout (no need to flatten)
    4. Do an xor of each drawing layer against the same layer, but xor purpose

    With Assura, Dracula, PVS and Calibre it's easier because they directly support having two different databases, whereas with Diva  you only have a single database, which complicates matters slightly.

    I seem to remember my app note had some scripts to automate adding the purposes and building the rule deck, and then some SKILL to do the above steps - but it's not exactly difficult. If you're using one of the other physical verificatioiin tools, it's simpler still.

    Regards,

    Andrew.

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