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AR# 50877

LogiCORE IP Fast Fourier Transform (FFT) v8.0 - Why do I get an error when using the FFT with floating-point interfaces and simulated in the Vivado simulation flow with ModelSim 10.1a?


If a Fast Fourier Transform v8.0 core configured with floating-point interfaces is simulated in the Vivado simulation flow with ModelSim, the ModelSim vopt stage crashes with an error similar to the following:

# ** Error: (vsim-3171) Could not find machine code for 'project_1/project_1.sim/sim_1/msim/xfft_v8_0.xfft_v8_0_e(xilinx)'.
# Load interrupted
# Error loading design


This is a known issue with the Fast Fourier Transform (FFT) when floating-point interfaces are selected and ModelSim 10.1a is used for simulation. This issue will be resolved in ModelSim 10.1c_1 and later.

Fast Fourier Transform cores configured with fixed-point interfaces are not affected by this issue.

To work around this issue, you will need to turn off the vopt option in the Vivado tool, see (Xilinx Answer 50907).

For a detailed list of LogiCORE IP Fast Fourier Transform (FFT) Release Notes and Known Issues, see (Xilinx Answer 29209).
AR# 50877
Date Created 10/03/2012
Last Updated 10/03/2012
Status Active
  • FPGA Device Families
  • ISE Design Suite - 14.2
  • Vivado - 2012.2
  • Fast Fourier Transform