[Magic-dev] Re: Magic VLSI

[R. Timothy Edwards]

Dear Gagi,

> I did however have some problems with your DEF and LEF readers. I am 
> fairly confident that the DEF files I have are correct since they have 
> been manufactured, but the def reader finds many errors. Is it always 
> required to read a LEF file before the corresponding DEF file? Also if 
> you know of any other freeware DEF readers that can visualize a circuit 
> please let me know. Thanks for such a great product!

There are not supposed to be any errors per se, but there are a number
of LEF and DEF statements and structures that are not implemented.  I
developed the routines based on output from specific software packages,
so you may have some piece of software that produces LEF or DEF files
that break my parser.  If so, I'd like some examples so I can fix it.
Also note that the Magic LEF and DEF routines depend on having a
techfile for magic that contains a "lef" block outlining the mapping
between LEF/DEF layers and magic layers.  Otherwise, Magic will make
some guesses that may very well be wrong.  Please read in the Magic
online documentation on the technology file format how to add a "lef"
section:

    http://opencircuitdesign.com/~tim/programs/magic/techref/maint2.html#lef

Since most DEF files contain references to macros defined in LEF files,
it is the usual practice to read a LEF file first, followed by the
corresponding DEF file.  Magic should have no trouble reading parts of
a DEF file without a corresponding LEF file, but I can't say how much
without trying it myself.

I'm not aware of any other freeware DEF readers, which is the main
reason I wrote one for Magic.  I'll post this message to the magic-dev
email list in case anyone reading the list knows of other freeware
LEF/DEF readers.

					Regards,
					Tim

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| Dr. R. Timothy Edwards (Tim)   | email: tim.edwards at multigig.com     |
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