Why do I get the error "Invalid output port data type" in my Simulink model?

When I try to run my Simulink model, I get the following errors in reference to a Stateflow block:

Invalid output port data type. Data type of output port 2 of 'regcontrol_model/RegControl' is invalid.

An error occurred while propagating data type 'uint8' through 'regcontrol_model/RegControl'.

I determined that the first error will occur on output 2 regardless of the order of my output ports.

I'm wondering why these errors occur, and are they related?

[Michael Girbino]

For further context, I previously got this error:

Error in default port dimensions function of S-function 'regcontrol_model/RegControl'. This function does not fully set the dimensions of output port 5

I didn't resolve the error, and instead I worked around it by temporarily removing output ports 5 and above. This allowed me to address other errors in the meantime. I've since added back those output ports, and that specific error no longer occurs.

A few interesting points:

1) It is not an S-function; it's a Stateflow block

2) The dimensions of the output port and the input port of the block that receives the signal were both defined in the Model Explorer.

3) Just like the above error, when I changed the order of the output ports, the error still occurred on port 5 (even for a different signal).

[TAB]

It would be nice if you can share your model or an example model.

[Michael Girbino]

In the process of removing my model's workspace dependencies so I can post the just the .slx file, I solved my problem.

I have a bus containing 32 constants whose values come from the MATLAB workspace:

In the definition of the bus object, my integer values are meant to be uint8:

TapLimitPerChange = Simulink.Parameter;
TapLimitPerChange.DataType = 'uint8';
TapLimitPerChange.Value = RCReg1.TapLimitPerChange; 

EquipElems(5) = Simulink.BusElement;
EquipElems(5).Name = 'TapLimitPerChange';
EquipElems(5).Dimensions = 1;
EquipElems(5).DimensionsMode = 'Fixed';
EquipElems(5).DataType = 'uint8';
EquipElems(5).SampleTime = -1;
EquipElems(5).Complexity = 'real';

...But in the class definition used by the object RCReg1, the integers are typed as int32:

properties (PropertyType = 'int32 scalar')
    TapLimitPerChange
end

This is why there was an error in data type propagation.

For reasons unknown to me, 'uint8 scalar' is not an acceptable PropertyType, so the solution is to typecast.

TapLimitPerChange.Value = uint8(RCReg1.TapLimitPerChange);

Answer 1

[Michael Girbino]

Answer is in the comments.