Check usage of Merge blocks

mathworks.hism.hisl_0015

Dependencies: Simulink^® Check™

Usage: High-Integrity System Modeling

Guideline: hisl_0015: Usage of Merge blocks

Description

Use this check to identify Merge blocks that are not directly connected to a conditionally executed subsystem and have the Allow unequal port widths parameter set to on.

Check Parameters

Use the Model Advisor Configuration Editor to define the scope of the analysis by specifying the input parameters.

Parameter	Description
Follow links	Specify whether to include content of library-linked blocks in the analysis. on (default) | off
Look under masks	Specify whether to include masked model elements in the analysis. all (default) | none | graphical | functional all — Check analysis includes all masked model elements. none — Check analysis excludes masked model elements. graphical — Check analysis includes only the graphical masked model elements. functional — Check analysis includes only the functional masked model elements.

Recommended Actions and Results

Review the violations that are flagged by the check and the recommended action for fixing the issue. After applying the changes, save the model and rerun the check analysis.

Modeling Condition	Recommended Action
A Merge block is not connected directly to a conditionally executed subsystem.	Revise the model so that the Merge blocks are connected directly to conditionally executed subsystems.
The Merge block parameter Allow unequal port widths is set to on.	Set the Merge block parameter Allow unequal port widths to off.
Multiple subsystems execute during a single time step in conditionally executed subsystems.	Specify execution of the conditionally executed subsystems so that only one subsystem executes during a time step.
The Outport block parameter Output when disabled is not set to held for any conditionally executed subsystems in the model.	Set the Outport block parameter Output when disabled to held for each conditionally executed subsystem being merged.

Capabilities and Limitations

• Does not check the execution order for conditionally executed subsystems

• Does not run on library models

• Analyzes only active variants only

• Performs model compilation

Version History

Introduced in R2018b