How to restart ModelSim simulation after each iteration from MATLAB script co-simulation?

I am working on a vhdl model that is simulated using hdl cosimulator app from simulink. The control and initialization steps are described as MATLAB script. The data is sent from matlab to simulink using from workspace blocks, then simulink fed the hdl function (Modelsim) using shared memory. After simulation process in Modelsim the data sent back to MATLAB. Currently I am facing the problem of timing, in the first iteration the ModelSim output is fine but in the 2nd and on, they delayed by a specific timing.

What I would like to do is how to restart simulation in modelsim from matlab script or from simulink after each iteration process ?

[Marc Erickson]

Within the HDL simulator, one can invoke a simulator restart which will reset all simulator state and reload the application that communicates with Simulink.

Unfortunately, there is no way to invoke this restart from within our application because doing so will hang the HDL simulator.

For each run of Simulink, it is safest to reinvoke the HDL simulator. For non-interactive use, using the "-c" option to vsim will ensure a faster startup and run time.

[Bilal MEJMAA]

Thank you so much for your answer. I am starting the cosimulation using this cmd "Sim_out = sim('Modelname')", I don't know where to use the -c option. I am also thinking of using a "File.do" that executes the "restart -force -nowave" cmd, but I have no idea how to execute a .d file from matlab script

Answer 1

[Bharath Venkataraman]

I believe Marc's suggestion is to close ModelSim after every run of Simulink and reopen it.

To start ModelSim, you typically use the vsim command from MATLAB. This may be something you do manually, or it may be executed in the model PreLoad, PostLoad or InitFcn (see Model callbacks). Move it to the StartFcn or InitFcn instead - this will start a new ModelSim each time you simulate (make sure you close ModelSim after you each simulation).

[Bilal MEJMAA]

Thank you so much for your response. I have tried the solution you have provided. It works at least to start modelsim I also found out that the cosim command

tclcmd = { ...
 'vsimulink "ModelName" -t 1ns -voptargs=+acc ;', ...   
'add wave "ModelName"/*;', ...
};
vsim('tclstart',tclcmd);

itself can be placed in matlab script and works also. Right after the cmd a pause instruction is necessary to give ModelSim enogh time to upload the interface. Now I need to close modelsim using a cmnd so I won't need to close it manually after each iteration. I have the intention to use CloseFcn and StopFcn, but I have no idea about the command to use.

[Marc Erickson]

Yes, great, the most convenient way to start the co-simulation is through vsim.m like you discovered!

If you desire to shut down ModelSim after each iteration, my suspicion is that you are not interested in interactively debugging the HDL simulation. In that case, you can likely get the behavior you are looking for by running the HDL simulation in the background--it will close the HDL simulator automatically.

Try the 'runmode' flag to vsim.m to specify running in batch mode.

'runmode' - Specify how to start the HDL simulator. One of the following strings:

'Batch' : On Windows, run in a non-interactive command window

On Linux, run in background with no window

'CLI' : Run in an interactive command-line window

'GUI' : Run with ModelSim graphical user interface

Default: 'GUI'

So your command would look like:

vsim('tclstart',tclcmd,'runmode','Batch')

[Bilal MEJMAA]

Thank you so much, the batch mode saved about 50% of the simulation timing.