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AR# 42680

13.1 PlanAhead - "ERROR: [HD-Constr 0] Could not find net 'CLK' (file = system.ncf, line = 54)"


From the PlanAhead tool, when loading the netlist design, I seethe following messages:

"INFO: [HD-UCFReader 0] Parsing UCF File : C:\my_projects\edk_tests\12_3_test1_pa\pn_project\system.ncf
ERROR: [HD-Constr 0] Could not find net 'CLK' (file = system.ncf, line = 54)
INFO: [HD-UCFReader 1] Finished Parsing UCF File : C:\my_projects\edk_tests\12_3_test1_pa\pn_project\system.ncf
WARN: [HD-Constr 0] No definition for the group 'sys_clk_pin' is found (file = system.ncf, line = 55)
WARN: [HD-Constr 1] Ignoring timing constraint since referred group or timespec is undefined (file = system.ncf, line = 55)"

The same constraints are resolved properly when the design is run through Project Navigator.


The issue occurs if an NCF file isclassified as a UCF file in the project and is set as the current constraint set.This could happen automatically during project import of an ISE Design Suite project if the projectdoes not have a UCF file.

Changing the NCF fileclassificationor changing the target constraints setresults in a successful compilation.

In the 13.2 PlanAhead tool,the GUI and Tcl commanddo not allow the setting of NCF as target and gives an error when trying to set NCF file(s) asUCF.

AR# 42680
Date 05/19/2012
Status Active
Type Known Issues
  • System Generator for DSP - 12.4
  • PlanAhead - 13.1