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AR# 53583

14.x PlanAhead - "[Designutils 20-31] Unrecognized symbol PPS..."


After upgrading a PlanAhead 13.4 project to PlanAhead 14.x, I get an implementation critical message for an input pin.
The pin PPS is then placed on an other location (AA34) instead of the constrained one (B20)

Following is from the error message:

[Designutils 20-31] Unrecognized symbol PPS ["D:/project_Test/project_Test.srcs/constrs_1/top.ucf":18]

Below are the constraints from the UCF:

NET "PPS" LOC = B20;

What is the reason for this and how do I overcome this warning?


PPS is a keyword which is used to group the partitioning pins of the design, so, this should not be used as the identifier in the design, Therefore, the tool gives this warning message and ignores it.

The 'PPS' keyword was added in the supported list of groups in the UCF parser for PlanAhead 14.1. This is the reason why the tool does not give any warnings in PlanAhead 13.4 (as it does not recognize this as keyword).

To avoid this issue, the name of the identifier should be changed.

AR# 53583
Date 11/11/2013
Status Active
Type General Article
  • Virtex-6 LXT
  • PlanAhead - 14