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Check usage of Merge block

Check ID: mathworks.jmaab.jc_0659

Guideline: jc_0659: Usage restrictions of signal lines input to Merge blocks


Identifies the blocks present in between a conditional subsystem and a merge block.

Merge blocks must have direct connections from conditionally executed subsystems. While using a Merge block take the following into consideration:

  • No blocks must be present in between the Merge and Conditionally executed subsystem blocks, including a virtual subsystem that does not affect the function of Merge block.

  • The Merge block can be nested inside any number of subsystems, if the preceding condition is satisfied.

This check requires a Simulink® Check™ license.

Check Parameterization

This check does not include sub-checks because the MAB modeling guideline provides only one sub ID.

For reference, the MAB guideline sub ID(s) that are recommended for use by the NA-MAAB and JMAAB modeling standards organizations are:

  • NA-MAAB — No recommendations

  • JMAAB — a

Results and Recommended Actions

ConditionRecommended Action
One or more blocks inserted in between a Merge and a Conditional Subsystem block.Make direct connections from Conditional Subsystem blocks to Merge blocks.

Capabilities and Limitations

  • Runs on library models.

  • Analyzes content of library-linked blocks. By default, the input parameter Follow links is set to on.

  • Analyzes content in masked subsystems. By default, the input parameter Look under masks is set to graphical.

  • Allows exclusions of blocks and charts.