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AR# 9468

14.x Constraints - How do I use the EXCEPT command within a FROM TO constraint?

Description

How do I use the EXCEPT command within a FROM TO constraint if a few of the paths within the FROM TO TIMEGRPs must be excluded?

Solution

For the FROM TO constraint, two TIMEGRPs must be created: one for the destination elements and one for the source elements. To exclude a signal(s) from either theTIMEGRP for the FROM TO constraint, you can use an EXCEPT command.

For example, the syntax would look like the following:

  • TIMEGRP new_srcgrp = srcgrp EXCEPT sig1;
  • TIMEGRP new_destgrp = dest_grp EXCEPT sig2;

If you must apply a FROM TO TIG constraint, make sure that the TIMESPEC line contains the TIG notifier as follows:

TIMESPEC "TS_constraintA" = FROM "new_srcgrp" TO "new_destgrp" TIG;

Additional Information

AR# 9468
Date Created 08/21/2007
Last Updated 12/15/2012
Status Active
Type General Article
Tools
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