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AR# 35677

12.1 Project Navigator - Constraints from UCF file(s) are being ignored


My project has a UCF file in it, but the timing allocation constraints seem to be ignored.

When I look at the command line for translate (NGDBuild), I see that the -uc switch is being sent correctly.However, I also see the -i switch on the command line.

In some cases, multiple -i switches are entered on the same command line.


This problem occurs for projects where the ".ucf" file is located in a remote directory (not in the project directory) that contains spaces.One "-i" switch is placed on the command line for each space in the directory path.The -i switch tells NGDBuild to ignore the constraints.

To work around the issue, place the UCF file in a directory that does not contain spaces, or put the UCF file in the project directory.

This issue is resolved in ISE Design Suite12.2.

Linked Answer Records

Associated Answer Records

Answer Number Answer Title Version Found Version Resolved
34432 Virtex-6 FPGA Connectivity Kit and Targeted Reference Design (TRD) - Release Notes and Known Issues N/A N/A
AR# 35677
Date Created 05/13/2010
Last Updated 12/15/2012
Status Active
Type General Article
  • ISE Design Suite - 12.1