LEF file in mosis library?

Discussion in 'Cadence' started by Lee, May 6, 2004.

  1. Lee

    Lee Guest

    Hi,

    I have a mosis library, but I cannot find the LEF file in this
    library. This library contains the cells (layout, abstract view and
    ....). Can I make the LEF file by myself for the existing
    library?How?Thanks,
     
    Lee, May 6, 2004
    #1
  2. Lee

    Simon S. IBM Guest

    Sure. For the macro LEF, use the cadence abstract generator
    (executable name is "abstract" strangely enough) in the DFII
    bin directory in the later releases.

    Big-time hint: Do NOT use the CIW menu selection:
    File ... Export ... LEF
    to generate macro lef. It works OK (barely) to generate
    technology LEF (which will require much hand editing if the
    P&R constructs are not yet in your dfii tech file); but it
    won't generate good macro lef.

    Yes, I know, you'd think that works. But, Cadence only puts
    energy into the abstract generator (they use it for all their
    tools, including the digital side) so it's the most powerful
    abstract editor on the planet (and, of course, it reads DFII
    data and outputs LEF on demand).

    With the cadence abstract generator, you'll never need another
    abgen tool ever again (once you learn how to use it).

    Simon
     
    Simon S. IBM, May 9, 2004
    #2
  3. Lee

    S. Badel Guest

    yep, except when it crashes without any notice,
    and despite the fact that it is incredibly slow.
    Abgen wasn't that bad after all...
     
    S. Badel, May 10, 2004
    #3
  4. Lee

    Ronald Guest

    Lee,

    We have been using Cadence Envisia abstract generator (abstract) for
    more than two years. It's powerful and good tool.
    However you need to have DPUX file, gdsII file, and Verilog stub file.
    I'm not sure if you have this DPUX file.

    I notice that you have "abstract view" already. You could
    actually generate the LEF file from Opus (File->Export->LEF) easily.

    Simon's comment on bad LEF file using File->Export->LEF is valid for
    layout view only.

    FYI, abstract view is generated by feeding LEF file into Opus. You
    just need to do the exact opposite step to get this LEF file.


    thanks,
    ronald
     
    Ronald, May 10, 2004
    #4
  5. Lee

    John Gianni Guest

    Everything Ron says above is correct.

    For example:
    If you already have a DFII abstract view (by whatever means),
    you can successfully use File->Export->LEF to create the LEF
    for the macro cells.

    And, Ron mentions basically that these DFII abstract views are
    often automatically generated when you import macro & technology
    LEF into DFII (File->Import->LEF, if I remember correctly).

    However, if you don't already have a DFII abstract view, nobody
    suggests you try to create macro LEF using File->Export->LEF.
    Everyone suggests you use the Cadence abstract editor (the
    binary is named "abstract") to create macro LEF for DFII layout
    cell views.

    The only thing I'd add to in Ron's email is this statement:
    The latest Cadence abstract generator can read almost any Cadence
    database, including CDBA & OpenAccess (which are the most common
    for DFII layout data); not just HLD DPUX data (which was the precurser
    to Genesis & OpenAccess).
     
    John Gianni, May 11, 2004
    #5
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