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AR# 8602

2.1i Ngdanno: Warning: Anno:26 - physical components for which 100% back annotation is not possible


Keywords: ngdanno, anno, 26, 100, back, annotation, possible

Urgency: Standard

General Description:
After using a blockram in a design the following warning comes back from ngdanno:
WARNING:Anno:26 - NGDANNO found physical components for which 100 percent
back-annotation is not possible. (These components are listed below.)


You can safely ignore this warning. The reason this warning is displayed is because
blockrams can have a huge denomination of logic. It can take ngdanno a long time
to parse the logical form of a blockram. To save on effort, ngdanno replaces the
logical form of the blockram with its physical component. This results in a fully simulatable
component which now contains hierarchy. All the names going into the blockram
will be the same. The blockrams name will change slightly to reflect the new hierarchy
but the user name for the blockram will be there.

This warning will disappear in the next release of the software.
AR# 8602
Date Created 02/11/2000
Last Updated 12/10/2001
Status Archive
Type General Article