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AR# 15484

5.1i Constraints Editor - A number of I/O standards for a Virtex-II are not listed


General Description:

I am attempting to set some of my I/Os to various I/O standards in Constraints Editor for my Virtex-II design, but many of the I/O standards are not listed. How do I select these I/O standards?


To select these, manually edit the UCF, adding the desired I/O standard.

This problem is fixed in the latest 5.1i Service Pack, available at:

The first service pack containing the fix is 5.1i Service Pack 2.

AR# 15484
Date Created 09/03/2007
Last Updated 01/18/2010
Status Archive
Type General Article