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AR# 17946

6.1i Timing Analyzer/TRACE - The FROM:TO constraint no longer performs a hold check


General Description:

When I compare two timing reports, one from design tools version 5.2x and the other from version 6.1i, my FROM:TO constraint no longer performs hold checks in the 6.1i version. How do I make the 6.1i FROM:TO constraint perform hold checks?


The 6.1i design tools include the new "fastpaths" option for TRACE/Timing Analyzer. This option allows you to determine which paths associated with each constraint are the fastest paths. With this switch turned on, the FROM:TO constraint will show you the fastest path with a minimum data path and a hold delay type shown. It will perform a hold check, but it will show you the fastest path that might have a hold violation.

This problem has been fixed in the latest 6.1i Service Pack, available at:

The first service pack containing the fix is 6.1i Service Pack 1.

AR# 17946
Date Created 09/03/2007
Last Updated 01/18/2010
Status Archive
Type General Article