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James_B's avatar
James_B
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3 years ago
Solved

Quartus Fitter Random Failing

I have a design for Cyclone VE that is about 90% full, and if I recompile the same design several times in a row, the design will intermittently fail on routing. The router settings have been at Pe...
  • sstrell's avatar
    sstrell
    3 years ago

    Choosing the performance option runs the Fitter "harder" to get better results. Even with minor changes, you're changing the initial seed used by the Fitter so the results can be different (including not finding a valid fit).

James_B's avatar
James_B
Icon for Contributor rankContributor
3 years ago

Thanks for the feedback here.

I have VHDL parameters at the most top level file, and that is where I set the version number of the project. What I have found is that when I sometime even just change a top level parameter, the fitter will fail, while it succeeded before. So essentially it's the same design, unless you want to say that the value of register should change the fitter results. That is why I am confused at the results here.

What I have also found is that at 92% the fitter fails consistently.