Load SimCoupler not loading and have warning error

I have SimCoupler with my doing same in the video I have a link: simcoupler video.mp4 - YouTube and I can't do anything with SimCoupler and they warring 1 error say:"Warning:Model 'PSimModel' was last saved using Simulink 5.1. Models last saved in releases before Simulink 6.0 (R14) may not function correctly in the current release. Save the models in an intermediate release (R2019b or older) then proceed." So, how I need fix and also which I need to do?

Answer 1

[Jack]

Hey Phung Vu,

The warning means your SimCoupler model was created in Simulink 5.1 (R13, from 2003), which is too old for direct compatibility with the latest MATLAB versions. Simulink requires models from very old versions to be converted through intermediate releases before they work properly.

How to Fix It

1. Find an older version of MATLAB

• You need MATLAB R2019b or older to first open and re-save the model.
• If you don’t have an older version, try contacting MathWorks support.

1. Open and Save in an Intermediate Version

• Open the model in MATLAB R2019b or an older version (preferably R14–R2019b).
• Save the model (.slx or .mdl).

1. Open in Your Current MATLAB Version

• After saving in R2019b or an intermediate version, open it in your current MATLAB.
• If you still see warnings, use Upgrade Advisor: upgradeadvisor('PSimModel')

• Follow the recommendations to update deprecated blocks.

Alternative if You Don't Have an Older MATLAB

If you can't find MATLAB R2019b or older, you can try:

• Rebuilding the model manually in your current MATLAB version if it’s small.

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[Phung Vu]

Hi Jack,

I great full to noitice your answer and thanks you so much.

By the way, I have one favorite question: If I convert my MATLAB R2023a to MATLAB R2019b or an older version, will it still work, or will something else happen? I am so confused because I forgot about it for 2 years, and I lost the ability to work on that. So, so maybe you can answer my question, can't you? Thank you, sir.

If have something else, please send me back and a alway check-in your question.

best regards,

Jack.

[Jack]

If you try to save a model in MATLAB R2023a and then open it in R2019b or an older version, it might not work properly due to compatibility issues. Newer MATLAB versions introduce updated blocksets, solver settings, and features that older versions don’t support.

What Will Happen If You Try?

1. Best Case: The model opens fine, but some newer features may be downgraded.
2. Common Case: You get compatibility warnings, and some blocks may not work as expected.
3. Worst Case: The model fails to open because older versions don’t recognize newer blocks.

How to Check Compatibility Before Converting

To see if your model will work in an older version, run:

saveAsVersion('PSimModel', 'R2019b')

or

save_system('PSimModel', 'PSimModel_R2019b.slx', 'Version', 'R2019b')

This will attempt to save the model in an older format, but some features might not transfer correctly.

If you need to work in an older version, the best option is to rebuild the model in R2019b manually using only supported blocks.

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