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AR# 977

FLOORPLANNER-XACT: Unable to load file <design>.lca / FPLAN : ERROR 1576 : Error in LCA file


Keywords: Xact, Floorplanner, Error 1576

Urgency: Low

Description: The design is mapped, placed and routed without any appearent problems. The <design>.lca file appears to be correct (ie. passes DRC, able to make bitstream, able to load design in editLCA). When entering the floorplanner the <design>.map file is read in without any problems, but when attempting to Read Placed Design floorplanner reports :

Unable to load file <design>.lca

Upon further investigation into the fplan.log file, the following error is reported :

*** FPLAN: ERROR 1576:
Error in LCA file: Block in Intnet statement is not previously defined,
or the statement does not contain one of the following: {F, G, H, PAD,
M, QY, QX}
on line <line number> of file "<design>.lca"
"<Line in .lca file>"
This is an internal error; please contact Xilinx support personnel.

A possible cause of this error is a pad or net with one of the following names : TCK, TDI, TMS, MD0, MD1, MD2, or TDO. Also can be caused if a bus is labeled MD[x:0].

These are special purpose input/output pad names and may cause problems with floorplanner if a net in the design has one or more of these names.


Change the name of any nets in the design with the following names : TCK, TDI, TMS, MD0, MD1, MD2, TDO or buses labeled MD[x:0]. Please follow standard naming conventions outlined in the XACT manuals when changing net names.
AR# 977
Date Created 08/31/2007
Last Updated 05/24/1999
Status Archive