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AR# 5422

15i Virtex DRC - DRC incorrectly flags a CLKDLL that drives both CLK0 and CLK2X offchip.


Running physical design DRC...
ERROR:xvkdr:41 - blockcheck: Improper DLL feedback loop. DLL dll_ext
has an invalid output. Since input pin CLKFB is being driven by a
GCLKIOB, either CLK0 or CLK2X must be used.


A fix for this problem will be included in version 2.1 due to be released in June 1999.
AR# 5422
Date Created 08/31/2007
Last Updated 10/05/2008
Status Archive
Type General Article