useAltergroup

[Dave Riedner]

Hey All,

I have been messing around with ic5.10.41.169, and when I run it with
a third party simulator I get warnings about the cdsenv files
associated with it. One specific warning is about useAltergroup. I
did a search on cdsdoc and didn't come up with much except how to set
useAltergroup. Does anyone know exactly what altergroups are? Is
this something new to ic5.10.41?

Thanks,

Dave

 

[Andrew Beckett]

altergroups were added in spectre back in IC443, I think. They allow
you to change several things at one time when doing alters in spectre
- for example, you can substitute one section of models for another in
a library file.

They are used by the corners tool. However, occasionally some model
files don't work (either because they contain models that don't
support altergroup, or because of front-end problems which have
probably been solved with the new front end in IC5141).

You can get the corners tool to not use altergroups by using:

spectre.envOpts useAltergroup boolean nil

in your .cdsenv file, or by using:

envSetVal("spectre.envOpts" "useAltergroup" 'boolean nil)

in your .cdsinit.

However, this is a spectre environment setting; I'm not sure why a
third-party simulator should be complaining about it.

Regards,

Andrew.

On 1 Oct 2004 14:38:53 -0700, dave_riedner@yahoo.com (Dave Riedner)
wrote:

Hey All,

I have been messing around with ic5.10.41.169, and when I run it with
a third party simulator I get warnings about the cdsenv files
associated with it. One specific warning is about useAltergroup. I
did a search on cdsdoc and didn't come up with much except how to set
useAltergroup. Does anyone know exactly what altergroups are? Is
this something new to ic5.10.41?

Thanks,

Dave