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new to QUCS - simulator doesn't simulate

nico
2022-10-12
2024-12-23
  • nico

    nico - 2022-10-12

    Hi every one,
    newbie on this forum and QUCS.
    I just started an Electric/Electronic engineer degree and i would like to use QUCS to simulate/test my schematics.
    I am running QUCS 0.0.19 on slackware current.
    The installation and launching of the program was flawless but when i try to simulate the circuit I always get a crah error message

    Starting new simulation on Wed 12. Oct 2022 at 09:52:43:242

    creating netlist... done.
    Starting /usr/bin/qucsator

    project location:
    modules to load: 0
    factorycreate.size() is 0
    factorycreate has registered:
    parsing netlist...
    checking netlist...
    netlist content
    1 Idc instances
    1 DC instances
    1 VProbe instances
    1 R instances
    1 Vdc instances
    1 TR instances
    creating netlist...

    Errors occurred during simulation on Wed 12. Oct 2022 at 09:52:43:261
    Aborted.
    then it shows a 100% filled blue progress bar
    and another message
    ERROR: Simulator crashed!
    Please report this error to qucs-bugs@lists.sourceforge.net

    I also installed ngspice as I read somewhere online that the ngspice simulator engine was helpful and complementary to QUCS but even for just a simple test circuit i.e. DC source and a resistor, with the simulation blocks added to the schematic fails (I attached a screenshot of the circuit i mentioned).

    Any help/advice would be gratefully welcome.

    Regards,

     
    • Felix

      Felix - 2022-10-12

      On Wed, Oct 12, 2022 at 07:56:32AM -0000, nico wrote:

      Hi every one,
      newbie on this forum and QUCS.
      I just started an Electric/Electronic engineer degree and i would like to use QUCS to simulate/test my schematics.
      I am running QUCS 0.0.19 on slackware current.
      [..]

      ERROR: Simulator crashed!

      We found a bug in Qucsator after the 0.0.20 release. It is likely the
      cause of your crash and has been fixed in the develop branch [1].

      NB: Qucs and Qucsator are developed separately now. Feel free to
      recombine and/or try with Gnucsator, NGspice, Xyce...

      [1] https://github.com/Qucs/qucsator/tree/develop

       
      • Tom Hajjar

        Tom Hajjar - 2022-10-17

        Is there a 0.0.20 release of Qucsator for Windows users?

        Does this release actually work better than 0.0.19, IE it can do transient analysis of circuits that 0.0.19 and the release of 0.0.20 I have won't do?

         
        • Felix

          Felix - 2022-10-17

          On Mon, Oct 17, 2022 at 12:27:32PM -0000, Tom Hajjar wrote:

          Is there a 0.0.20 release of Qucsator for Windows users?

          Hi Tom.

          AFAIK, there is only one 0.0.20 release for all platforms. The bugfix
          in develop mentioned earlier is not included, it may just crash.

          Does this release actually work better than 0.0.19, IE it can do
          transient analysis of circuits that 0.0.19 and the release of 0.0.20
          I have won't do?

          Don't know -- If you need transient simulation, or a replacement for
          Qucsator, or something that is still under development, try Gnucsator.

           
          • Tom Hajjar

            Tom Hajjar - 2022-10-17

            What is the procedure for replacing Qucsator with Gnucsator?

             
            • Felix

              Felix - 2022-10-17

              On Mon, Oct 17, 2022 at 02:13:06PM -0000, Tom Hajjar wrote:

              What is the procedure for replacing Qucsator with Gnucsator?

              Gnucsator provides an alternative executable that reads Qucs netlists
              and produces .dat files similar to Qucsator. There is an environment
              variable that can act as an override, and other ways to select it. See
              gnucsator/README.md for details.

               
  • nico

    nico - 2022-10-12

    NB: Qucs and Qucsator are developed separately now. Feel free to
    recombine and/or try with Gnucsator, NGspice, Xyce...

    Thank you for your input. I am not new to compiling on linux but i am not sure what "recombine" really means.
    Would you be so kind to advise me accordingly?
    In the meantime i will compile QUCS 0.0.20 and QUCSator0.0.20 (but again, i am not sure how to combine them).
    Regards,

     

    Last edit: nico 2022-10-12
  • nico

    nico - 2022-10-12

    I upgraded qucs-0.0.19 to 0.0.20 however, I have not installed the separate qucsator yet.

    I wanted to have a try at another very basic circuit (dc source, 2resistors in series, one ground and a voltage probe).

    I tried to simulate the schematic and it just crashed.
    Details: qucs stayed open, i only saw a white window opening in the background for a millisecond, but no error. Is it because it needs quscator?
    i will try to install it tomorrow and any other advise will be greatly appreciated.
    Regards,

     
  • nico

    nico - 2022-10-13

    OK, so I successfully downloaded, compiled and installed
    1- qucs-0.0.20-rc2 and,
    2- qucsator-develop
    and I am not sure whether, or not, it solved the Simulation error issue.

    When I run the simulation (F2) a window appears and close so quickly that I can't even read a single word in it and, the tab switches from "test_circuit.sch" to "test_circuit.dpl" (which I believe it to be the simulation display page). Accidentally, I pressed F2 again and this time the error window appeared, in the display tab and, the error msg is below:

    ~~~
    Starting new simulation on Thu 13. Oct 2022 at 23:01:43:633

    creating netlist... done.
    Starting /usr/bin/qucsator

    project location:
    modules to load: 0
    factorycreate.size() is 0
    factorycreate has registered:
    parsing netlist...
    checking netlist...

    Errors occurred during simulation on Thu 13. Oct 2022 at 23:01:43:643
    Aborted

    checker error, no actions defined: nothing to do

    ~~~.
    It is a different error msg from the previous one as it seems that no actions defined. Could someone tell me if I am supposed to pass some settings or inputs to the simulator before running F2?

    Sorry, it's only my third use of QUCS and I am really keen in learning it if I manage to run simulations.

    Thank you for any/all suggestions.

     

    Last edit: nico 2022-10-13
    • Felix

      Felix - 2022-10-13

      On Thu, Oct 13, 2022 at 09:13:18PM -0000, nico wrote:

      OK, so I successfully downloaded, compiled and installed
      1- qucs-0.0.20-rc2 and,
      2- qucsator-develop
      and I am not sure whther, or not, it solved the Simulation error issue.

      It probably did.

      checker error, no actions defined: nothing to do

      Maybe there is no "simulation command" element in your schematic. Look
      at the examples.. There are some in the qucs-test repo.

      (Not so sure, play with the examples either way.)

       
  • nico

    nico - 2022-10-14

    Maybe there is no "simulation command" element in your schematic. Look
    at the examples.. There are some in the qucs-test repo.

    Would you be so kind to point out where these examples are? Or where the repo is?
    I couldnt find it

     
    • Felix

      Felix - 2022-10-14

      On Fri, Oct 14, 2022 at 05:56:31AM -0000, nico wrote:

      Maybe there is no "simulation command" element in your schematic. Look
      at the examples.. There are some in the qucs-test repo.

      Would you be so kind to point out where these examples are? Or where the repo is?
      I couldnt find it

      Sure, https://github.com/Qucs/qucs-test

      cheers
      felix

       
      • nico

        nico - 2022-10-14

        Thank you so much.

        So, i managed to see the simulation of the test folder you linked; does it mean that my qucs is ready-to-go? Only need to learn about it now?

        Cheers

        p.s.: I had found that github page but I run away as soon as i saw python lines and commands (

         
  • nico

    nico - 2022-10-14

    so, this is what I call "weird software behaviour"!

    QUCS on my desktop (with qucsator) installed separately seems to open and report no error (when I run F2) in about half of those schematics in the testsuite folder.

    The weirdness comes when i test QUCS on my laptop: identical behaviour before I install QUCSator.

    Now, i am wondering, am i really "playing" uselessly with those files? Is my installed QUCS actually running any simulation when I hit F2? What is the point of installing QUCSator? or, are these files just showing what was done by the author?

    Once again, apologies for the newbie's questions and a little details would go a long away with my stress level! ))

    p.s.: the snapshots are of the 1st (no_error) and 2nd (error) folders

     

    Last edit: nico 2022-10-14
    • Felix

      Felix - 2022-10-17

      On Fri, Oct 14, 2022 at 06:50:07PM -0000, nico wrote:

      Now, i am wondering, am i really "playing" uselessly with those files?
      Is my installed QUCS actually running any simulation when I hit F2?
      What is the point of installing QUCSator? or, are these files just
      showing what was done by the author?

      These are good questions.

      When you run the simulation from the GUI (presumably by pressing F2),
      Qucs dumps a flat netlist with commands into ~/.qucs/netlist.txt. A
      reference to this file is then passed to qucsator (a subprocess). The
      output ends up in some .dat file, and various plotting widgets in Qucs
      read from it. You can run qucsator manually, to remove any doubt.

      $ qucsator -i ~/.qucs/netlist.txt # or so.

      cheers
      felix

       
  • nico

    nico - 2022-10-17

    These are good questions.

    Out of curiosity, do you have it working on your box? Linux or Windows?

    Today, I had a lecture intro on LTspice and I tried to set most of the recognizable parameters identical to what we did in the lab. No go!

    No disrespect to the developers and their hard work but I really to know if it's me or the package so, I took an appointment with the lab technician, tomorrow, and will ask him:
    a) for help to set up those (unknown to me) parameters or
    b) check whether adjusting other parameters I can have this 'qucs' to work
    before I will opt to install wine and try to run windows applications in the 'wine-sublayer'.

    It will be such a shame bcos the interface is really simple and user-friendly (very similar to that of LTSpice). It just need more work (which I will be happy to offer in a few years when, hopefully, i learn more about coding and electronic).

    One more question:
    in the screenshot attached, all the buttons circled/pointed in red (and no matter what components i add) seems to be inactive. This is the same also if I use one of those testsuite files/schematics downloaded from github. Again, am i missing something? or not doing something correct?

    Thanks

     
    • Tom Hajjar

      Tom Hajjar - 2022-10-17

      I use Qucs, Qucs-S, QucsStudio and LTSpice. I've used dozens of circuit analysis programs dating back to punch cards and time share.

      If you want to do AC/DC and "simple "RF analysis and DON'T need to use manufacturers Spice models, Qucs and QucsStudio are OK.

      If you want to do Transient analysis, DON'T use Qucs or QucsStudio. You will pull your hair out getting even simple circuits to simulate. Until I can use Gnucsator on Windows, my opinion stands.

      Qucsconv in Qucs is abysmal, limiting the ability to convert Spice models. Qucsconv in QucsStudio is 100x better but still has many issues.

      If you want to do AC/DC/Transient and "simple" RF analysis and DO need to use manufacturers Spice models use Qucs-S. Qucs-S uses ngspice or xyce Spice engines. Ngspice has an active community that will respond but updates are slow in coming. LTSpice will work with more manufacturer's Spice models than ngspice. xyce Spice is tailored more for IC design simulations.

      Qucs-S RF support is lacking. Qucs has more components and works with S-parameter files. It will be a while before Qucs-S supports S-parameter files.

      If you want to do AC/DC/Transient, "simple" RF analysis AND want a very experienced community that will help you in a few hours, use LTSpice. LTSpice also supports the most manufacturers Spice models.

       
    • Felix

      Felix - 2022-10-17

      On Mon, Oct 17, 2022 at 08:32:54PM -0000, nico wrote:

      Out of curiosity, do you have it working on your box? Linux or Windows?

      Both Qucsator and Gnucsator works on Debian/testing. Qucs (the GUI) is a
      bit tricky, because of the Qt3 dependency. I have not touched it in a
      while. (There's Qucs-s and Modular Qucs work in progress, and they don't
      depend on Qt3...)

      It will be such a shame bcos the interface is really simple and
      user-friendly (very similar to that of LTSpice). It just need more
      work [..]

      It's tempting (and a bit off-topic). Chances are you won't get very far
      if a simple and user-friendly interface is your primary motivation. We
      need to collaborate on a free/libre and extensible circuit simulator
      that can compete with and replace commercial ones. There is a learning
      curve involved with that -- but please try and climb it.

       
  • nico

    nico - 2022-10-19

    There is a learning
    curve involved with that -- but please try and climb it.

    OK! I see light on the other side of the channel.

    With the help of a 'spice' guru I managed to get 'qucs' to simulate on my slackware-current laptop and desktop (it was a matter of inputting the correct values and a couple of diagrams, which I didn't do before). So, I can CONFIRM that it works. I just need to get armed of a lonnnng ladder (time) now and start the climb.

    I agree that open source should compete and outrank commercial software but I am also aware that user-friendly GUI will attract more non-tech minded users.

    Thank you for now.

     

    Last edit: nico 2022-10-19
  • Tom Hajjar

    Tom Hajjar - 2024-12-23

    I just received notification for this old post on 12/23/24....

    My comments about Qucs-S not supporting Qucs RF components are not valid anymore.

    Qucs-S now uses qucsator-rf allowing it to run in "Qucs" mode.

    ngspice and xyce Spice now support S-parameter analysis. ngspice also supports s-parameter files.

     

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