MATLAB: How to run or generate an A2L file from a model with multiple model references containing duplicate named test points in MATLAB R2015b

simulink coder

I have a main, top-level model which contains multiple model references to the same model.

Inside the referenced model there are signals marked as test points and have the storage class 'ExportedGlobal'. This is done in order to generate an A2L file during code generation.

The duplicate model referencing is not just for testing purposes, the multiple instances of model reference will be in the final build, with the test points included.

When I attempt to run the model in this configuration, I receive the following error message during model update:

'Configuration Parameters > Model Referencing > Total number of instances allowed per top model' is set to 'Multiple' for model 'RefModel'.  Block 'RefModel/Gain' of this model has an output signal with a global storage class. This is not allowed in a model configured to be referenced multiple times.  Consider setting the configuration parameter 'Total number of instances allowed per top model' to 'One' or changing the signal's storage class.

Best Answer

This is due to the limitations of model referencing in Simulink. Simulink considers the referenced model as a reusable system and generates as a function call in the code. It cannot have the custom storage class, 'Exported Global', for the intermediate outputs of a referenced model. Please refer to the following documentation link for limitations of using model referencing:

https://www.mathworks.com/help/releases/R2015b/rtw/ug/simulink-coder-model-referencing-limitations.html

To work around this limitation, you can create additional output ports on the referenced model to bring those signals into the main model. Then, declare them as 'ExportedGlobal' in the main, top-level model to have them generated in the A2L file. At this time, this is the only workaround available.

Please refer to the attached image for an example of how this workaround could be modeled. This image represents the top level model containing two duplicate model references. The signal which has been designated a test point is outputted as "mySignal_1" and "mySignal_2". Making these signals test points from the main model should allow A2L file generation, and for your model to run successfully.

Related Solutions

MATLAB: Is it possible to log internal signals in the generated code of a Simulink model that has multiple instances of a model reference

The workflow is possible in 17b by using one of the following ways:

1. Setting the storage class of the signal to SimulinkGlobal. With this approach, the signal is preserved and its name is not mangled. Please note that in R2018a, SimulinkGlobal was renamed to "Model default". If the model’s default storage class for internal data is "Default" then the behavior is the same as described above. If the model’s default storage class is a single-instance-only storage class (like ExportedGlobal) then this will error out.

2. You may enable signal logging by checking the following option on the Model Configuration Parameters: Code Generation > Interface (Advanced Parameters) > MAT-file logging

3. You may enable Testpoint for the signal. Please uncheck the option "Ignore testpoints" setting in ConfigSet or the signal may be optimized away from generated code. With this option, the signal is preserved but name may be mangled.

MATLAB: Do I receive an error saying “Multiple conflicting usages of identifier” when I run the model that contains referenced models in Simulink 6.6 (R2007a)

The error is due to a name conflct when generating code for the referenced model. For referenced models, the generated code has a series of constructs in the "modelname.c" file.

For example, for the referenced model "tm.mdl", the "tm.c" file has the following named constructs:

    { "mr_tm_B", MDL_INFO_ID_GLOBAL_RTW_CONSTRUCT, 0, 1, (void *) "tm" },
    { "mr_tm", MDL_INFO_ID_GLOBAL_RTW_CONSTRUCT, 0, 1, (void *) "tm" },

Similarly, for the referenced model "tm_B.mdl", the "tm_B.c" file has the following named constructs:

    { "mr_tm_B_B", MDL_INFO_ID_GLOBAL_RTW_CONSTRUCT, 0, 1, (void *) "tm_B" },
    { "mr_tm_B", MDL_INFO_ID_GLOBAL_RTW_CONSTRUCT, 0, 1, (void *) "tm_B" },

Both models have a construct named "mr_tm_B", which causes confusion while running the model.

As a workaround, if there are multiple referenced models in a Simulink model, the models should have unique names and not have any of the following at the end of the name:

 _NSZC
 _Xdis
 _Xdot
 _X
 _RTM
 _ZCE
 _C
 _P
 _DW
 _B
 _rty_0
 _rtu_0
 _Term
 _initialize
 _Start
 _GlobalTID
 _ConstP

A second workaround is to run a referenced model as an inlined model (Normal mode) instead of generating code for the referenced model (Accelerator mode). You can choose the simulation mode for the model from the "Model Reference Parameters" options (select "Model Reference Parameters" by right-clicking the referenced model.) Note that:

1. If the referenced model is run in "Normal Mode", then you must select the "Inline parameters" check box in the Optimization pane of the Configuration Parameters dialog box.

2. This solution is only valid for Simulink v.6.7 (R2007b) or later versions.

3. This solution is only valid when simulating the model. If you generate code for a target, the name confusion issue persists.

Best Answer

Related Solutions

MATLAB: Is it possible to log internal signals in the generated code of a Simulink model that has multiple instances of a model reference

MATLAB: Do I receive an error saying “Multiple conflicting usages of identifier” when I run the model that contains referenced models in Simulink 6.6 (R2007a)

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