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AR# 34039

ModelSim - (vsim-19),(vopt-19) Failed to access library 'unisims_ver'


When I run a simulation using code that instantiates Xilinx primitives, the following error occurs:

# ** Error: (vsim-19) Failed to access library 'unisims_ver' at "unisims_ver".
# No such file or directory. (errno = ENOENT)


# ** Error: (vopt-19) Failed to access library 'D:\Xilinx\11.1\ISE\verilog\mti_se\6.5b\nt/unisims_ver' at "D:\Xilinx\11.1\ISE\verilog\mti_se\6.5b\nt/unisims_ver".
# Permission denied. (errno = EACCES)

How can I resolve these issues?


In order to simulate designs with instantiated behavioral or timing primitives, ModelSim requires that the Xilinx libraries are referenced in the "modelsim.ini".Follow these directions to resolve the issues above:

  1. If you have not already done so, run the Simulation Libraries Compilation Wizard (compxlib) tool to pre-compile the Xilinx libraries. Refer to Answer 33715for information on how to use this tool
  2. Compxlib generates a modelsim.ini in the current working directory with the appropriate library mappings to the pre-compiled libraries. Modelsim will use this file for intiialization if:
    a) the "modelsim.ini" is located in the simulation working directory
    b) the MODELSIM environment variable is set with the absolute path to the location of the "modelsim.ini" file

Refer to the Synthesis and Simulation User Guide in the Documentation Centerfor more information about setting up your simulator environment for Xilinx designs.

If the information in this Answer Record does not address the simulation errors, please contact Xilinx Technical Support using the Contact Supportmethods.

AR# 34039
Date Created 05/04/2010
Last Updated 05/16/2012
Status Active
Type Error Message
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