In matlab code, create a generic element using
myElement = Simulink.BusElement;
You can set the properties of the new element by directly accessing the values. For example
myElement.Name = 'mySignal';
myElement.DataType = 'uint8';
Once you are finished with the element, you can add it to the bus:
myBus = Simulink.Bus; % You only need to do this once when you create the bus object
myBus.Elements(end+1) = myElement; % Add the element to the bus
Another way to create bus objects is to implement the bus in simulink with all its inputs with correct data types and sizes. For example like this:
Select the bus creator block and run the following code:
Simulink.Bus.createObject(gcs, gcb);
This will put a bus object named like the output signal of the bus creator, in this case myBus, in the workspace.
