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GOMEZ_IT's avatar
GOMEZ_IT
Icon for Occasional Contributor rankOccasional Contributor
2 years ago
Solved

Questasim INTEl EDITION counter simulation

Hello. I'm using this vhdl code to make an 8 bit counter with enable. Quetasim Intel fpga does not increment the counter regularly (defined as variable). It goes from 'X' to '1' and then it...
Simulation
  • roeekalinsky's avatar
    roeekalinsky
    2 years ago

    @GOMEZ_IT, I think you were right, this looks like a simulator problem.

    I was able to reproduce your original observation, and it appears to be a bug in older versions of Questa, up to the version shipped with Quartus Pro 23.3.

    The version of Questa shipped with Quartus Pro 23.4 doesn't appear to exhibit this symptom. Or at least not with this test case. But I don't know if this was a known bug that got fixed, or if the symptom just went away with other changes in Questa. That's something you should confirm with Intel and/or Mentor/Siemens.

    For ease of testing, I modified your test case slightly to be able to run in a more minimalist command line mode, with console messages in lieu of waveforms. See attached zip.

    Running this test case with all the simulators I currently have available to me I got the following results:

    • Questa from Quartus Pro 22.2: bad
    • Questa from Quartus Pro 22.4: bad
    • Questa from Quartus Pro 23.1: bad
    • Questa from Quartus Pro 23.2: bad
    • Questa from Quartus Pro 23.3: bad
    • Questa from Quartus Pro 23.4: good
    • Modelsim DE 2022.4: good
    • ghdl 4.0.0-dev: good

    See attached log.txt for the above results.

    -Roee

SyafieqS's avatar
SyafieqS
Icon for Super Contributor rankSuper Contributor
2 years ago

I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, Please login to https://supporttickets.intel.com/, view details of the desire request, and post a feed/response within the next 15 days to allow me to continue to support you. After 15 days, this thread will be transitioned to community support. The community users will be able to help you on your follow-up questions.


p/s: If any answer from community or Intel support are helpful, please feel free to mark as solution, give Kudos and rate 5/5 survey


  • roeekalinsky's avatar
    roeekalinsky
    Icon for Contributor rankContributor
    2 years ago

    @SyafieqS,

    Can you confirm whether or not this was in fact a known bug that was fixed in the Questa version that shipped with Quartus Pro 23.4?

    Thanks,

    -Roee