Initialise property with simulink.bus information located in sldd

Hi all

The code below is working as intended, however the 'ST_FB_TRIGGERBUFFER_DATARECORD' needs to be available in the base workspace. I have the definition stored in a data dictionary (FB_TriggerBuffer.sldd), how to change the code below, so it will search the definition in this data dictionary?

Thanks in advance

Ludo

classdef FB_TriggerBuffer < matlab.System

% System Flags

% =====================================

methods (Static, Access = protected)

function flag = supportsMultipleInstanceImpl(~)

flag = true;

end

end

% Properties declaration

% =====================================

% Public properties

properties (Access = public)

nWriteIndex uint16 = 1; % [] Index to the record which will be written

arrstDataBuffer = repmat(Simulink.Bus.createMATLABStruct('ST_FB_TRIGGERBUFFER_DATARECORD'),1,3); % [] Buffer holding the supplied data

stEmptyDataRecord = Simulink.Bus.createMATLABStruct('ST_FB_TRIGGERBUFFER_DATARECORD'); % [] Empty data record

end

Answer 1

[Poorna]

Hi Ludo,

I understand that you would like to access the definition of 'ST_FB_TRIGGERBUFFER_DATARECORD' from the data dictionary 'FB_TriggerBuffer.sldd' instead of the Base workspace.

You can follow the below steps to access data from a data dictionary:

1) Declare a class property say ‘FB_TriggerBufferObj’ and initialize it with the data dictionary object using the “Simulink.data.dictionary.open” function.Here is the sample code for the same:

FB_TriggerBufferObj = Simulink.data.dictionary.open('FFB_TriggerBuffer.sldd') 

2) To access the variable in the class methods, you can use the “getSection” function to retrieve the section in which the entry is stored. Then, use the “getEntry” function to retrieve the entry. Finally use the “getValue” function to obtain the value of the desired entry.Here is the sample code for the same:

dataSec = getSection(FB_TriggerBufferObj, 'Design Data'); 
dataEntry = getEntry(dataSec, 'ST_FB_TRIGGERBUFFER_DATARECORD'); 
val = getValue(dataEntry); 

3) Now, you can use the retrieved value as usual in the code.

To know more about the functions “Simulink.data.dictionary.open”, “getSection”, “getEntry”, and “getValue”, please refer to the following documentation.

• https://www.mathworks.com/help/simulink/slref/simulink.data.dictionary.html

Hope this Helps!

Best Regards,

Poorna.

[Ludo Houben]

Hi Poorna

There is a small typo 'FFB_TriggerBuffer.sldd' but your answer is clear. I accepted it, although for me this solution is not working. This solution can not be used in 'code generation' simulation mode.

For others with the same issue. I solved it by running a Matlab scipt loading all used bus definitions in to base workspace.

Note: My main 'PlayGroundStructs.sldd' calls several lower level *.sldd files.

%% Load struct definition
	Simulink.data.dictionary.open("PlayGroundStructs.sldd");
	structEntries = find(getSection(Simulink.data.dictionary.open("PlayGroundStructs.sldd"), ...
								'Design Data'), '-value', '-class', 'Simulink.Bus');					% Get all simulink.bus definitions from SLDD file
	for index = 1:length(structEntries)																	% For all found simulink.bus definitions
		assignin('base',structEntries(index).Name,getValue(structEntries(index)));						% Create struct
	end
	clear index structEntries;																			% Delete temporary variables