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AR# 39395

12.3 XST - "ERROR:Xst:2750 - line 1: Bad project format. Valid format is '[library_name] file_name'"


According to the XST User Guide, the following format for the ".prj" file is supported:

[Language] [library name] [file name]

However,modifying the project to be specifically VHDL orVerilog rather than MIXED, results in the following error:

"ERROR:Xst:2750 - line 1: Bad project format. Valid format is '[library_name] file_name'"

If you have the project set up as VHDL or Verilog, then the format should be:

[Library name] [file name]


This error occurs only with the new XST Parser which did not provide consistent behavior while handling different formats. This works with XST if targeting Virtex-5 or older devices.

Starting in 13.4, XST supports only mixed language format by default. Also,13.4 XST does not support the "-ifmt" switch. The "-ifmt" option has been removed from ISE 13.4 Project Navigator. The 13.4 XST user guide has also been updated with this change by removing the"-ifmt" option from the document.

In earlier versions, you can work around this issue by either choosing MIXED language, or modify the ".prj" file.

Linked Answer Records

Associated Answer Records

Answer Number Answer Title Version Found Version Resolved
32927 XST - What is new in XST for Virtex-6 and Spartan-6 devices? N/A N/A
AR# 39395
Date Created 10/12/2011
Last Updated 01/17/2013
Status Active
Type Known Issues
  • Spartan-6 LX
  • Spartan-6 LXT
  • Spartan-6Q
  • More
  • Virtex-6 CXT
  • Virtex-6 HXT
  • Virtex-6 LX
  • Virtex-6 LXT
  • Virtex-6 SXT
  • Virtex-6Q
  • Less
  • ISE Design Suite - 12.1
  • ISE Design Suite - 12.2
  • ISE Design Suite - 12.3
  • More
  • ISE Design Suite - 12.4
  • ISE Design Suite - 13.1
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