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AR# 52912

PlanAhead - CONFIG PROHIBIT constraints applied in a UCF file are not shown on the prohibited sites

Description

I have a UCF file with several CONFIG PROHIBIT constraints used to prevent locations from being used.Some of the prohibited sites have a prohibit (do not enter) symbol shown in the Device layout.However, many do not.

Am I doing something wrong? Are the constraints still used?

Solution

The constraints should still be used but are not visually shown with the symbol. Check the sites in question to be sure they have the PROHIBIT == 1 attribute. This issue has been seen when the CONFIG PROHIBIT constraint uses a wildcard (asterisk) or a comma delimited values or in ranges.

Example:

CONFIG PROHIBIT = RAMB36_X3Y*;
CONFIG PROHIBIT = RAMB36_X3Y2,RAMB36_X3Y3;
CONFIG PROHIBIT = SLICE_X94Y25:SLICE_X101Y25;

Using the equivalent XDC, all prohibited sites appear with the prohibited symbol
AR# 52912
Date Created 11/14/2012
Last Updated 01/08/2013
Status Active
Type Known Issues
Tools
  • PlanAhead