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AR# 25316

9.2i Virtex-5 MAP - ERROR:LIT:440 - CLKIN of GTP_DUAL symbol "xyz" is not driven by an IBUFDS, IBUFGDS or GT.

Description

My design ran successfully in ISE version 9.1i but now in 9.2i it fails with the following Logical DRC error. Is this a valid error?

Error Message:

ERROR:LIT:440 - CLKIN of GTP_DUAL symbol "xyz" is not driven by an IBUFDS, IBUFGDS or GT.

Solution

The Virtex-5 RocketIO User's Guide (http://www.xilinx.com/xlnx/xweb/xil_publications_index.jsp?category=User+Guides),page 72, shows a clocking scheme called GREFCLK clocking where the CLKIN pin is driven by a BUFG or BUFR. A new Logical DRC check in 9.2i is overly restrictive and incorrectly flags errors on valid configurations where the CLKIN pin is driven by a BUFG or BUFR.

This problem is being evaluated for a future software fix. Meanwhile, this check can be disabled by setting the following environment variable:

Windows

SET XIL_MAP_NO_GT_CLKIN_DRC=1

Linux and Solaris

setenv XIL_MAP_NO_GT_CLKIN_DRC 1

For general information about setting ISE environment variables, see (Xilinx Answer 11630).

AR# 25316
Date Created 09/04/2007
Last Updated 12/15/2012
Status Active
Type General Article