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  3. how to pass parameters and do some calculations

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how to pass parameters and do some calculations

Danilo P
Danilo P over 14 years ago

Hi,

In cell cap the cdf parameter "c" is defined and set as c = [@test:%:12.0].

Cell cap is instantiated in the schemati cell "myTest". In the cell myTest the user property "test" is declared as string ans set to 15.

Everything is fine till now, netlist is generated correctly  and parameter value is passed properly through the hierarchy. Now I need that parameter c in the cell "cap" doesn't inherit exactly the value from property "test" defined on the parent cell, but it should be generated with a calculation: for instance 2*test+15. How to do that?

 Thank you, Danilo

 

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  • Andrew Beckett
    Andrew Beckett over 14 years ago

    Hi Danilo,

    What tools are supposed to understand this expression? Are you using CDS_Netlisting_Mode set to Analog (e.g. for Analog Design Environment). 

    Regards,

    Andrew.

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  • Andrew Beckett
    Andrew Beckett over 14 years ago

    Hi Danilo,

    I believe you've logged a service request on this, SR  42359188, so I'll leave my colleague in customer support to deal with this rather than us both working on it.

    Best Regards,

    Andrew.

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  • Danilo P
    Danilo P over 14 years ago

    Hi Andrew, I logged the SR you pointed out for a different topic, that is the creation of placement rows with the Placement Planning Form", but I agree with you, so please ignore the post in this forum I filled for the same matter.

    Instead, concerning this post, any suggestion is welcome. About your question: I have to create hspice netlist for UltraSim, and CDS_Netlisting_mode = "Compatibility".

    Thank you and sorry for the confusion I created.

    Danilo 

     

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  • Andrew Beckett
    Andrew Beckett over 14 years ago

    Hi Danilo,

    Apologies - I posted the reply to the wrong post (I don't think I can fix that without messing up the others - I'll see).

    Anyway, if using the UltraSim or hspiceD netlister, you should not really be using NLP expressions to pass parameters. Better would be to use the AEL pPar() expression, and then you can have expressions as the Analog Expression Language handling will come into play.

    That's really the way that AEL/CDF-based netlisters are intended to work. NLP is more for older "digital" flows which are separate from ADE.

    Regards,

    Andrew.

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  • Danilo P
    Danilo P over 14 years ago

    Hi Andrew,

    here what I am doing.

    In the cell cap I set CDF parameter cell as parseAsCEL=YES and parseAsNumber=YES. Value of the parameter is pPar("test")*2.

    Cell cap is instantiated in "myTest". In the cell myTest the user property "test" is declared as string and set to 15.

    My expectation is to find in the netlist the value 30 when the device cap is instantiated, but I found pPar("test")*2 as the expression hasn't been evaluated. Something is wrong in my settings?

    Thank you, Danilo

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