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AR# 22615

7.1isp2 Timing Analyzer/trce/speed file - Spartan-3E Period Checks are updated for DCM


Keywords: frequency

Urgency: Standard

General Description:
When I look at my timing report, the DFS and DLL frequency buttons on the Spartan-3 DCM do not affect the CLKIN frequency and the overall performance of the DCM. Are the DFS and DLL frequency button suppose to do something?


The Spartan-3E DCM autoranges the CLKIN frequency. Consequently, the DFS and DLL frequency buttons on the DCM are meaningless. The speed files are updated according to the data sheet specifications.

This problem has been fixed in the latest 8.1i Service Pack available at:
The first service pack containing the fix is 8.1i Service Pack 1.

AR# 22615
Date Created 12/28/2005
Last Updated 03/27/2007
Status Archive
Type General Article