Stats

  • Locked Locked
  • Replies 2
  • Subscribers 143
  • Views 1973
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

dbGetTrueOverlaps issue - Very important

SUBBHAREDDY

 Hi Guys

The below function checks only for overlapping of wires and not any other pins.

This gives i.d if it is overlapping with wire,but not any other pins and transistors.

How to overcome this issue ?

connWire = dbGetTrueOverlaps( cv list(7.94375:-2.6 8.44375:-2.6 ) list("wire" "drawing") 0:0 )

 I checked it practically in schematic window.

How to overcome it,Pls help me to resolve this issue ?

 

Thanks and regards

Subbhareddy

 

 

  • It is doing exactly what you told it to do. You told it to get overlapping shapes with an lpp of "wire drawing". Here is the documentation for the third argument to dbGetTrueOverlaps:

    Specifies the layer name or number. If t, dbGetTrueOverlaps produces instances, mosaics, or shapes (the default). If nil, dbGetTrueOverlaps produces only instances and mosaics.

    The examples in the documentation expand on this. If the third argument is a layer string then it will find shapes on that layer with a drawing purpose. If it is a list of just the layer string, it will find shapes on all purposes for that layer. If it is an lpp (list of layer and purpose) then it will find shapes only on the lpp you specified.

    If you want to find pins and transistors, you will need to do one of these:

    1. Give a third argument of nil so that only instances are returned
    2. Give a third argument of t so that ALL shapes (regardless of layer) and all instances are returned and then post process this to keep what you want.
    3. Have a foreach loop go through the layers you are looking for and run dbGetTrueOverlaps multiple times. If you want to get pins (in the schematic, these are instances), then you'll need to specify the lpp in the pin and be sure to check at least one level deep in the hierarchy (0:1). If you want to get overlapping wires in a lower level instance, again, you'll have to check at least one level deep in the hierarchy.
    4. If you just want wires and instances (remember, a pin is an instance) but don't want labels, etc. then I recommend having one call to dbGetTrueOverlaps with list("wire" "drawing") for the wires and one call with nil for the instances.

    When you start getting overlaps that are deeper than 0:0, you are going to get a nested list of results that you must process. The list will include the instances traversed along the way to the lowest object.

    Please take a look at the documentation. It is very good. I can almost always find what I need to know.

    Derek

  • Thanks

     It works fine.

     

    Thanks and regards

    Subbhareddy

    Extn :3158

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.