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AR# 24462

9.1i Timing Analyzer - "WARNING:ConstraintSystem:12 - In file: maxskew_test.ucf(4): Loading a 'MaxSkew' constraint from a UCF file is not supported at this time"

Description

When running Place and Route or the timing tools, I receive the following warning:

"ARNING:ConstraintSystem:12 - In file: maxskew_test.ucf(4): Loading a 'MaxSkew'

constraint from a UCF file is not supported at this time. This constraint

specification will be ignored."

Solution

Starting in 8.2i, the timing tools try to read the constraints file as part of a feature expansion that will allow, in 9.1i, the timing tools to change some of the constraints in the UCF file. This message can be safely ignored. For timing analysis, the ".pcf" and ".ncd" are used. Timing Analyzer does not support a ".ucf" constraint for MAXSKEW, only ".pcf". This should be updated for 9.1i.

AR# 24462
Date Created 09/04/2007
Last Updated 01/18/2010
Status Archive
Type General Article