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AR# 36249

12.3 PlanAhead - Cannot print the default I/O standards to the .ucf file


I am attempting to assign the default I/O standards, LVCMOS25 and LVDS_25, for all of the I/Os in the design from the PlanAhead software, but when I look at the UCF, it does not write out the constraints.

Is there a way to do this from the PlanAhead software?


This is a known issue in the PlanAhead software. Currently, there is no way to write out the default I/O standards from the PlanAhead tool. This problem is to be addressed in a future release of the PlanAhead software. If you need a complete list of I/Os and their properties, use the pad report from reportgen.

This issue has been resolved in the 13.1 PlanAhead software.
AR# 36249
Date Created 07/07/2010
Last Updated 07/08/2011
Status Active
Type Known Issues
  • PlanAhead - 12.1
  • PlanAhead - 12.2
  • PlanAhead - 12.3