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AR# 18723

6.1i Floorplanner - IOSTANDARD constraint is removed from UCF when specified after a LOC using '|' (pipe) to separate them

Description

Keywords: IOSTANDARD, Floorplanner, remove, UCF, FNF, |, pipe

Urgency: Standard

General Description:
I opened my design in PACE and created constraints for LOCing my pins and setting IOSTANDARDs as shown in the following example:

NET "a" LOC = "G6" | IOSTANDARD = LVTTL ;
NET "b" LOC = "G5" | IOSTANDARD = LVTTL ;

After opening Floorplanner and either writing the constraints or saving the ".fnf" file, I found the following constraints:

NET "a" LOC = "G6" ;
NET "b" LOC = "G5" ;

Floorplanner is removing the IOSTANDARD constraint when it is specified after the LOC constraint.

Solution

Xilinx recommends making a backup of your UCF if you are going to use Floorplanner. This issue will be fixed in our next major release.
AR# 18723
Date Created 01/05/2004
Last Updated 02/21/2007
Status Archive
Type General Article