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AR# 4839

2.1i: Timing: OFFSET in/after and out/before give negative values in timing report


Urgency: Standard

General Description:

When constraining a design with OFFSET IN/AFTER and/or

OUT/BEFORE, with no PERIOD constraint, the period is

assumed to be 0 ns. But there is no warning or error

message during implementation. The only message that will

appear is the following when there is not Period constraint or

the Offset is to tight.

There is no minimum offset greater than zero for this constraint.



Create a Period constraint for the design.

AR# 4839
Date Created 08/31/2007
Last Updated 01/18/2010
Status Archive
Type General Article