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AR# 5520

1.5i Virtex Back Annotation - Ngdanno issues warning stating that 100% back annotation is not possible


A Virtex case has been seen where ngdanno reports that 100% back-annotation is not possible, however the three reasons stated do no appear to apply to this case. Map was not run with the
-oe or -os options, there are only a few flops contained in the design (no Carry logic), and the MAP
report does not give any specifics about logic being replicated during physical mapping.


A fix for this problem is included in the 1.5i Service Pack 1. For details
on this Service Pack see http://www.xilinx.com/techdocs/5514.htm
AR# 5520
Date Created 08/31/2007
Last Updated 06/13/2002
Status Archive