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AR# 22556

8.1i ISE - Project Navigator is sending the wrong source file to implementation and simulation processes


Keyword: top, NGDBuild, simulator

During synthesis, implementation, or simulation, an error or warning message is issued specifying that the Design Unit (DU) cannot be found. Looking at the command history (Design Utilities -> View Command Line Log File), I see that the wrong source file was sent to the process which is failing.


A problem was found in Project Navigator where the wrong source in hierarchical design is selected as the design unit regardless of which source is selected as top. This problem has been seen most often when the "top" source files have been changed after some processes have been run or when using incremental design flow.

In most cases, running Project -> Cleanup Project Files will reset the project to the proper state and allow the correct top-level module to be sent to Project Navigator processes.

This issue is fixed in the latest 8.1i Service Pack, available at:
The first service pack containing the fix is 8.1i Service Pack 1.
AR# 22556
Date Created 09/04/2007
Last Updated 03/26/2008
Status Archive
Type General Article