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AR# 23382

9.1i ISE - Running Project Navigator Implementation process in Xplorer mode fails and issues error message: "ERROR: Nonexistent ucf file"


Keywords: timing, closure, constraints, UCF, implement, translate, MAP, place, route, PAR, place and route, place & route

When I you run the Xplorer flow from Project Navigator on a design that does not contain a UCF with constraints, Xplorer fails and issues a message indicating that the top_module.ucf is missing:

"ERROR: Nonexistent ucf file "<project path>/<top_module>.ucf."
Xplorer run failed."


Xplorer is a timing closure technique that runs the implementation process through multiple iterations using different options to achieve a desired result. Using the constraints from the User Constraints File (UCF), together with optimization strategies such as global optimization, timing-driven packing and placement, register duplication, and cost tables, Xplorer implements the design in multiple ways to meet timing goals. Xplorer mode requires that a valid ".ucf" file containing timing constraints is added to the project to establish a target for implementation.

Consult the ISE Help topics for more information on Xplorer mode.
AR# 23382
Date Created 09/04/2007
Last Updated 04/16/2009
Status Archive
Type General Article