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AR# 39694

PlanAhead - PlanAhead does not read pin assignments from the NCF file


When I view my Netlist Design in PlanAhead, I notice that my pins are not being mapped.

My NCF file and EDF file have the same file names.

If I run NGDBUILD and then view the assignments with xdm_viewer, the pins get assigned there.


While NGDBUILD requires that the filenames of the NCF and the EDF files match, PlanAhead does not.

PlanAhead looks for the filename of the NCF to match the top-level module name in the EDIF.

If the Top-level EDIF module name does not match the file name, there will be a disconnect.

There are two workarounds available:

  • Rename the NCF to match the name of the top level module name of the EDF.
  • Change the extension of the NCF to UCF*

    *Until release 13.1, NCF will take priority over UCF, keep this in mind when changing extensions.
AR# 39694
Date 08/11/2014
Status Archive
Type General Article
  • PlanAhead - 14.1
  • PlanAhead - 13.1
  • PlanAhead - 12.1
  • PlanAhead - 11.1
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