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AR# 19264

6.2i XST - XST is not considering LUT delays during timing for Spartan-3


Keywords: Spartan, 3, timing-driven

Urgency: Hot

General Description:
XST is not taking LUT delays into consideration when a Spartan-3 part is targeted. Since XST is a timing-driven synthesis tool this leads to very poor quality of results.


Download the attached file and place it in the "$XILINX/spartan3/data/" directory to replace the old file. The file works for all platforms and all 6.2i versions. This problem will be fixed in an upcoming service pack.

NOTE: XST 6.1i does not have this problem.

This issue has been addressed in the latest 6.2i Service Pack, available at:
The first service pack containing the fix is 6.2i Service Pack 3.
AR# 19264
Date Created 04/06/2004
Last Updated 07/18/2007
Status Archive
Type General Article