AR# 10643: 3.3i Foundation ISE Project Importer - Default net names are renamed by the exporter.
3.3i Foundation ISE Project Importer - Default net names are renamed by the exporter.
Keywords: ISE, Project Navigator, Importer
General Description: For schematics where the net from the IPAD or to the OPAD is not explicitly named, the Foundation VHDL netlister will add characters to the beginning and end of the default name. Any UCF constraints concerning these pads will then be invalidated if that VHDL netlist is used to implement a design.
For Example: $Net00016_ is renamed to X36_NET00016_X95 in the VHDL netlist.
As a general rule, all nets or busses of this sort should be named before attempting to import the project into ISE.