Cannot run Cosimulation due to error "Failed Cannot connect to 'ModelSim' HDL simulator"

I have added the path to my Questa Sim simulator using the addpath command, but am still receiving the "Cannot connect to 'ModelSim' HDL simulator." error. What additional steps do I need to take to allow the Simulink Workflow Advisor to perform cosimulation with Quest Sim?

While the workflow advisor shows the above error, I see the following warning in the MATLAB command line:

Warning: Could not determine 32/64bit mode from 'Model Technology ModelSim - INTEL FPGA STARTER EDITION vsim 2021.1

Simulator 2021.02 Feb 3 2021

Answer 1

[Ramtej]

Hi Brad,

I understand that you have installed QuestaSim and added the folder to your MATLAB path. Please ensure to check whether the QuestaSim is installed correctly and is visible from MATLAB by running the following command.

!questasim

If you get an error saying "questasim is not recognized as an internal or external command…" Add QuestaSim to your Windows search path as well.

To add QuestaSim to your Windows search path, please follow these steps:

1. Right-click on the Start Button.
2. Select “System” from the context menu.
3. Click “Advanced system settings”.
4. Go to the “Advanced” tab.
5. Click “Environment Variables…”
6. Click variable called “Path” and click “Edit…”
7. Click “New”
8. Enter the path to the folder containing the binary you want on your PATH.

Once the system path has been updated, the ‘!questasim’ command should work from the MATLAB command window. An additional check you can perform is to execute the following command at the MATLAB Command Window.

vsim

This command should launch a new instance of QuestaSim and verify that QuestaSim is configured properly. You can now run Cosimulation with QuestaSim.

Hope that helps.

[Marc Erickson]

We cannot support HDL Cosimulation for the Intel FPGA Starter Edition version of ModelSim because it lacks the underlying PLI support for our application.

We do support Questa versions of the simulator as enumerated here (for the current release):https://www.mathworks.com/help/hdlverifier/gs/supported-eda-tools.html#bt16i4l-7

(Note that this page reflects the version we tested against. Other versions are likely to work as well.)

As noted in a previous response, ensure you are getting the correct version of the tool when invoking from within MATLAB:

>> ! vsim -version

It should show use of the 64b version of a (fully featured) ModelSim or Questa simulator, for example:

Questa Sim-64 vsim 2023.2 Simulator 2023.04 Apr 11 2023