Changing Simulink Real-Time Workspace Variable

I am currently working on Simulink Real Time (with Speedgoat). I want to change some variables in Model Workspace, from outside Speedgoat (using UDP connection or Serial Port).

I can't use assignin because it is not supported for code generation. Is it possible to do this?

Answer 1

[Jonas]

You should use the command setparam. Typical command is: setparam(tg,'speed_setpoint',100) for changing parameter 'speed_setpoint' on your target tg = slrt.

More info.

[Calvin Watson]

I am also running Simulink Real Time deployed onto a SpeedGoat. When I try set_param the error 'Cannot change parameter Constant value while simulation is running' is displayed.

It works fine when I run the simualtion (CTRL T) just on the machine. When i run the model via the Real-Time run tab I get the error above.

[Jonas]

Try setparam, not set_param. It is a different command.

[Calvin Watson]

Thank you Jonas. I can now edit tunable params during running :). I am using a GUI (matlab app) to alter the inputs into the model ad hoc. Is setparam the only method of driving the realtime model using the GUI?

[Jonas]

setparam is a direct way, and until recently the only way to build a MATLAB App that interfaces with a SLRT application.

With the recent update to SLRT, I believe they have expanded the way you can interface with a SLRT application. An alternative way now would be to use Instrumentation.

I have no experience with it but it should be a more convenient way of reading signals and displaying them on elements, and changing parameters without having to manually program it all.

For displaying a real-time graph, I used to program capturing of signals linked to a timer object to refresh the graph in a MATLAB App, but they made it more user-friendly from what I understand.