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AR# 11203

LogiCORE Direct Digital Synthesis (DDS) v3.0 - "Sim has a problem implementing the select core. Implementation netlist will not be generated."


Keywords: generate, CORE Generator 3.1i, IP Update 3, version 3, Direct Digital Synthesizer, DDS, block ROM

I am using the DDS v3.0, targeting a Virtex-II device. I have chosen to implement using block ROM, and am running Windows. When I select the "Generate" button, the following error is reported:

"Sim has a problem implementing the select core. Implementation netlist will not be generated."

In the main CORE Generator window, the following messages are reported:

"ERROR: An internal error has occurred. To resolve this error, please consult the Answers Database at http://support.xilinx.com
ERROR: Sim has a problem implementing the selected core. Implementation netlist will not be generated.
ERROR: SimGenerator: Failure of Sim to implement customization parameters core my_dds
ERROR: Core my_dds did not generate EDIF implementation netlist (.EDN) file.
WARNING: Warnings and/or errors encountered while generating my_dds (Direct_Digital_Synthesizer 3.0) All output products requested may not have been generated.
ERROR: Elaboration failure for core Direct_Digital_Synthesizer
ERROR: Elaboration of core Direct_Digital_Synthesizer failed."


These errors occur because, when CORE Generator is started up from the Windows "Start" menu or ISE, it starts up in $XILINX/bin/nt. This happens regardless of the project directory's setting. An MIF file is generated wherever CORE Generator is started; the MIF file is needed for core generation; when it cannot be found, the above errors occur.

You can work around this issue in two different ways:

1. Open a DOS box, and change directories to your project directory at the DOS prompt. Next, start up CORE Generator GUI by typing "coregen" at the DOS prompt. You can now successfully generate the core as you normally would.

2. Use Windows Explorer to go to $XILINX/bin/nt and find the .mif file. It should be named "filename.mif", where "filename" is the component name you specified previously from the CORE Generator GUI. Then, move this .mif file to your project directory. You can now generate the core successfully.

NOTE: Each time you create a new project or generate more cores, it may be necessary to move the MIF file to your project directory.
AR# 11203
Date Created 03/14/2001
Last Updated 04/05/2006
Status Archive
Type General Article