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AR# 17679

6.1i ISE - Project Navigator/Synplicity: "@E:"<directory>\<source>.v":nn:n:nn:nn|Reference to undefined module <unisimcomponent name>"


Keywords: UniSim, unisim.v, DCM, IBUFG, BUFG, Verilog, ISE, Synplicity

Urgency: Standard

General Description:
Project Navigator does not add the "virtex2.v" as a source file in the Synplicity project file for Virtex-II/Verilog designs. As a result, Synplicity reports error messages similar to the following for any instantiated UniSim component.

"@E:"c:\testproj\testaw1.v":27:4:27:11|Reference to undefined module DCM"
"@E:"c:\testproj\testaw1.v":76:6:76:21|Reference to undefined module IBUFG"
"@E:"c:\testproj\testaw1.v":80:5:80:18|Reference to undefined module BUFG"


The Synpllicity 7.2.2 and later tools automatically include their own "unisim.vhd" library file, making it no longer necessary for Project Navigator to include the line "add_file -VHDL -lib unisim {c:Synplicilty/Synplify_72/bin/lib/xilinx/virtex2.vhd}" in the project file created in ISE and send it to Synplify.

This line was consequently removed from VHDL project files, and the equivalent line was also removed from Verilog projects. However, since Verilog does not use the same concept of "libraries" as does VHDL, the "unisim.v" file should actually be added to a Verilog Synplify project.

Verilog users (who are instantiating Xilinx components in their designs) can work around this problem in one of two ways:
1. Insert an 'include unisim.v line in the Verilog file (include unisim in the code), or
2. Add "unisim.v" to the Project Navigator project.

This problem has been fixed in the latest 6.1i Service Pack, available at:
The first service pack containing the fix is 6.1i Service Pack 1.

NOTE: Synplify users working with Synplify 7.1 with ISE 6.1i may also have trouble with VHDL projects if Xilinx primitives have been instantiated. Synplify 7.1 did not include the "unisim.vhd" file, and the ISE integrated flow has now removed that library from the Synplify project file.
AR# 17679
Date Created 07/25/2003
Last Updated 02/07/2006
Status Archive
Type General Article