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AR# 19103

6.3i XST - PAR Regional_Clock-0 is impossible to route


Keywords: BUFG, BUFR, Virtex-4, global, clock, network

Urgency: Standard

General Description:
In my Virtex-4 designs that instantiate a BUFR, XST infers a BUFG on the same net and an "impossible to be routed" message occurs to indicate that my design cannot be routed.


This problem has been fixed in the latest 6.3i Service Pack available at:
The first service pack containing the fix is 6.3i Service Pack 1.
AR# 19103
Date Created 03/05/2004
Last Updated 07/18/2007
Status Archive
Type General Article