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cjak's avatar
cjak
Icon for Occasional Contributor rankOccasional Contributor
8 days ago

QuestaSim - Fatal error simulating altpll-ip

Hi,

I am trying to simulate design including the altpll-ip, but I get this fatal error:

I have changed timescale to ps with no luck.

Any suggestions?

7 Replies

  • cjak's avatar
    cjak
    Icon for Occasional Contributor rankOccasional Contributor

    hm, adding reset to init the PLL caused the error to come back :-)

    I added stimuli controlling the areset-input on the PLL. Setting reset high for 10 us, then low.

    • RichardT_altera's avatar
      RichardT_altera
      Icon for Super Contributor rankSuper Contributor

      Have you tried running the simulation using the NativeLink simulation flow?
      Without the design files, it is challenging to debug and understand the root cause. If possible, creating a simplified design would help us investigate further.

      Otherwise, the currently identified possible root cause is described in the KDB below, which I believe you have already reviewed:
      https://community.altera.com/kb/knowledge-base/fatal-sigfpe-floating-point-exception/342914

      Regards,
      Richard Tan
       

      • cjak's avatar
        cjak
        Icon for Occasional Contributor rankOccasional Contributor

        No, I have not tried NativeLink simulation flow before. How is it done?

        Changing to ps makes no difference.

  • cjak's avatar
    cjak
    Icon for Occasional Contributor rankOccasional Contributor

    Hi, sorry for slow response. I have been away for 2 days.

    I rebuilt my project in QuestaSim, and the error is gone, but I do not seem to get the PLL to lock. Do I need to include more than the vhd-file for the PLL in my project?

    I am sorry but I cannot send you my project....unfortunately.

  • RichardT_altera's avatar
    RichardT_altera
    Icon for Super Contributor rankSuper Contributor

    Hi cjak​ 

    Could you please share the design (Project > Archive Project) and the testbench so I can reproduce the issue on my side?
    If you have any confidential IP, you could create and share a simplified design that can replicate the problem, or you may private message me the design.
    You will need to zip the .qar design and attach the .zip file in forum.

    Regards,
    Richard Tan

  • cjak's avatar
    cjak
    Icon for Occasional Contributor rankOccasional Contributor

    Reset is at high-level when simulation starts...

    Input-frequency is 24MHz...