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AR# 20856

10.1 CORE Generator - When generating Reference Design Core, the following message occurs: "Valid License Not Found"


The CORE Generator displays the following error message when I try to customize a reference design. The core is selected in CORE Generator or through Project Navigator using Project -> New Source -> IP (CORE Generator and Architecture Wizard).

"Valid License Not Found

You do not have a valid license to generate the implementation netlists for the <Core_name> core, because FLEXlm Error: No such feature exists (-5,21)

For more information, or to purchase a license for this core, please refer to http://www.xilinx.com/ipcenter/ipevaluation/"

However, the link provided in the error message does not contain any information about licenses for the core in question.


This message appears for reference designs (such as the Aurora and Virtex-4 Tri-Mode Ethernet cores) because, by default, they are shipped without a license. However, unlike many of the separately licensed LogiCORE cores, these reference designs only support full licenses.

Reference designs also differ from LogiCOREs in the type of outputs produced (typically plain text HDL source). Evaluation versions are not required for this reference design because full electronic licenses are available at no additional charge to ISE customers, and the generated output is plain text HDL source code. The only requirement is that customers are required to register for and install a "full" license.

To obtain a license for a reference design, refer to the corresponding product page, which can be found at:

AR# 20856
Date 07/28/2010
Status Archive
Type General Article