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Necessary to cover pin in hierarchical layout?

kenc184

Why is it necessary to touch the pin in a sub-block in VXL for "show incomplete nets" to recognize the connection?  The tool recognizes the net as being connected to the pin, so why isn't simply connecting to the net rather than the pin good enough?  Below is an example, the circuitry to the left of the purple prBoundary line is a sub cell, the signal "blank" is connected in M1 to an M1 path in the sub-block but does not touch the pin. The connection is not recognized as complete.

  • Andrew Beckett

    This is because the extract depth is set to 0, so it only extracts the connectivity in top level shapes, and so the only lower-level shapes it considers are pins. Usually, in well-formed layout this is sufficient and is more efficient as a result. You can however increase the extract depth to more than 0 if needed to address this.

    Andrew

  • kenc184
    in reply to Andrew Beckett

    Given this, how would I assign two pins (e.g.) to one net on different layers?  I often have a cell which is used in multiple locations. It would be nice to be able to assign a pin to (e.g.) M1 and M2 in two different locations on the same net without it being a global.  So far, i haven't found a property on the pin to allow this.

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