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AR# 5851

1.5i SP2 Virtex back annotation - Ngdanno issues warning stating that 100% back annotation is not possible.


A 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 available in the 1.5i Service Pack2:

(Xilinx Solution #5887)

AR# 5851
Date Created 03/09/1999
Last Updated 04/10/2000
Status Archive
Type General Article