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AR# 9892

3.1i Foundation ISE - Switching Synthesis Tools can result in NCF file errors


Keywords: Project Navigator, XST, FPGA Express, NCF, Constraints

Urgency: Standard

General Description:
When a design is synthesized using XST, an NCF file is always generated.
If the synthesis tool is then changed to FPGA Express and the design is
resynthesized, a new EDIF file is generated. By default, a new NCF is not
generated. If a new NCF is not generated, then NGDBUILD will utilize the
FPGA Express EDIF file and the XST NCF file, resulting in errors.


Delete the old NCF file.
AR# 9892
Date Created 08/09/2000
Last Updated 01/16/2003
Status Archive
Type General Article