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AR# 12585

4.1i Constraints Editor - The LVDS CLK input is not displayed as a clock


General Description:

In the Constraints Editor, the LVDS input clocks in Virtex-II (clk_p and clk_n) do not appear in the Global tab; instead, they appear in the Ports tab. How can I ensure that these clocks appear in the Global tab?


This problem is fixed in the latest 4.1i Service Pack, available at:


The first service pack containing the fix is 4.1i Service Pack 2.

AR# 12585
Date Created 08/29/2007
Last Updated 01/18/2010
Status Archive
Type General Article