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create or delete subcell from CDF callback

smikes

A pcell can instantiate subcells at creation. Is there a way to add or remove them via a CDF parameter through the callback?

For example, say I have a resistor that gets added to, or removed from, a schematic based on a CDF parameter.

Thanks,

Steven

Parents
  • mbracht

    I would suggest to create the subcell conditionally as part of the PCell creation code. Something like:
    (when <somePcelParam> (dbCreateInstance ...))
    And then provide a CDF param for that PCell parameter.

  • smikes
    in reply to mbracht

    Wouldn't this check just run once at PCELL creation time? Toggling the parameter afterwards would have no effect, right? 

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  • smikes
    in reply to mbracht

    Wouldn't this check just run once at PCELL creation time? Toggling the parameter afterwards would have no effect, right? 

Children
  • Andrew Beckett
    in reply to smikes

    It's not really clear what you're trying to do.

    If the PCell is a hierarchical PCell, then a parameter of that PCell could define whether the sub-instance is created or not. If you later change the value of that parameter, the PCell code would get re-evaluated and then in the new sub-master (variant), the instance would or would not be created, dependent on that parameter.

    If you were asking to have a CDF callback for a component which when chosen will create a second instance (at the same level as the main instance that you're editing the properties of), then you shouldn't do that - this is beyond how the tools are supposed to be used and would almost certainly break lots of flows. CDF callbacks should only be affecting parameters on the instance being created/edited, and should not be used for other side effects.

    Andrew.

  • mbracht
    in reply to smikes

    nope - changing a Pcell parameter forces a reevaluation of the underlying SKILL code.

  • smikes
    in reply to mbracht

    Yup you're right it works, thanks!

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