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AR# 8038

8.1i TRCE/Timing Analyzer/Constraint - Can I constrain a path (FROM:TO) through an LD latch in the IOB? (lat_d_q)


Can I set a path constraint on a continuous path through an LD latch in the IOB?


No. As the latch is considered to be combinatorial logic, the FROM:TO constraints must be set from pad-to-latch and latch-to-pad.

To enable a constraint to go through the latch, add the following line to the PCF/UCF:

AR# 8038
Date Created 08/21/2007
Last Updated 11/18/2010
Status Archive
Type General Article