MATLAB: Do I get an error about “hidden signal specification block” and signal object properties in Simulink

simulink

I have a large model with a bus signal being created from subsystem outports. I see an error about "hidden signal specification block" and signal object properties set incorrectly but I cannot find this block since it is hidden. The signals coming in to the bus have signal properties from a signal object created in a MATLAB Script.

Best Answer

In this case, the hidden block is not editable, and the error refers to the MATLAB script that defines the signal properties for that signal object being created. In Simulink, one of the signals coming into the bus is specified by this object and the object has old, incorrect signal properties. Check the MATLAB script to make sure the signal's data type matches what the Simulink bus has defined as input.

Related Solutions

MATLAB: Are Simulink.Signal objects’ Max and Min not enforced in the generated code

Currently, the "Max" and "Min" properties of "Simulink.Signal" objects have no effect on the generated code. These parameters are meant for simulation range checking only, as described in the following documentation:

https://www.mathworks.com/help/releases/R2017b/simulink/slref/signal.html#property_d119e294167

https://www.mathworks.com/help/releases/R2017b/simulink/slref/signal.html#property_d119e294244

With the "Simulation range checking" diagnostic set to "warning" or "error", Simulink will notify you when the selected signal exceeds the range set by the Minimum and Maximum parameters of the corresponding "Simulink.Signal" object.

In order to conduct a form of range checking in the generated code, one approach is to include a "Saturation" block. This block will effectively limit the signal between the specified saturation values.

MATLAB: How to retrieve the name of a signal coming into a Bus Creator block in Simulink, when the signal is not propagated from a Subsystem, without having to update the diagram

The ‘SignalHierarchy’ property of the Outport of the bus can be used to extract the name of the children signals. Though the name of the Inport signals is not available before the model is updated, if the children signals of the Outport are accessed, then the name is visible even before the model is updated.

Here is an example on how to extract the name of the signal from the command line, by using the 'SignalHierarchy' property.

   busCreator = 'model2/Subsystem1/Bus Creator1';
   ph = get_param(busCreator,'PortHandles');
   sh = get_param(ph.Outport, 'SignalHierarchy')
   sh.Children(1).SignalName

Best Answer

Related Solutions

MATLAB: Are Simulink.Signal objects’ Max and Min not enforced in the generated code

MATLAB: How to retrieve the name of a signal coming into a Bus Creator block in Simulink, when the signal is not propagated from a Subsystem, without having to update the diagram

Related Question