Answers Database


FPGA Express: How to disable clock period specification


Record #4185

Product Family: Software

Product Line: Synopsys

Product Part: FPGA Express

Product Version: 2.0.3

Problem Title:
FPGA Express: How to disable clock period specification


Problem Description:
Urgency: Standard

General Description:
When exporting timing constraints from FPGA Express, constraints for all valid clocks and paths are written, regardless of whether or not you wish to constrain that path.

How does one disable a clock or path timing specification?


Solution 1:

If you do not care about the timing of a certain clock, simply place a very loose timing specification on that clock.



Solution 2:

With Express 3.2 and newer, all timing constraints are written to an NCF file.
This file may be edited by the user, so unwanted constraints can be simply
removed from this file.




End of Record #4185 - Last Modified: 08/06/99 16:15

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