Documentation

Linked Blocks

When you add a masked library block or a Subsystem block from a Library to a Simulink® model, a referenced instance of the library block is created. Such referenced instance of a library block is a called a linked block and contains link or path to the parent library block. The link or path allows the linked block to update when the library block is updated.

To locate the parent library block of a linked block, right-click the block and select Library Link > Go To Library Link (Ctrl + L). The Go To Library Block option is available only for the blocks that are linked and not for the Simulink built-in blocks. To prevent unintentional disabling of links to a library, use the locked links option on the library. For more information, see Lock Links to Blocks in a Library.

Note

The tooltip for a linked block shows the name of the referenced masked library block.

When you edit a library block (either in Simulink Editor or at the command line), Simulink updates the changes in the corresponding linked blocks. The outdated links are updated when you:

  • Simulate or update the model.

  • Use the find_system command.

  • Diagram > Refresh Blocks (or press Ctrl+K)

  • Load the model or library (only visible links are updated).

  • Use get_param to query the link status of the block (see Control Linked Block Programmatically).

    Note

    You can use the LinkStatus parameter or the StaticLinkStatus parameter to query the link status.

    • LinkStatus: First updates the linked block and then returns the link status.

    • StaticLinkStatus: Returns the link status without updating the linked block.

    Selective usage of StaticLinkStatus over LinkStatus can result in better Simulink performance. For more information on StaticLinkStatus and LinkStatus, see Control Linked Block Programmatically.

Rules for Linked Blocks

  • You can change the values of a linked block parameter (including the existing mask).

    Note

    The Allow library block to modify its contents check box in the Initialization pane of the library block must be selected.

  • You cannot set callback parameters for a linked block.

  • If the reference library block of a linked block is a subsystem, you can make nonstructural changes such as changing the parameter value of the linked subsystem. To make structural changes to a linked block, disable the link of the linked block from its library block (See Disable or Break Links to Library Blocks).

Linked Block Terminology

TerminologyDefinition

Parent library block

Library block from which the linked blocks are referenced.

Linked block

Reference instance of a library block that contains links or path to its parent library block.

Locked links

Prevents unintentional modification of a linked block. For more information, see Lock Links to Blocks in a Library.

Disabled links

Library links that are temporarily disconnected from their parent library block. For more information, see Disable or Break Links to Library Blocks.

Restore links

Restores the disabled link of a linked block to their parent library block. For more information, see Restore Disabled or Parameterized Links.

Break links

Permanently breaks link of a linked block from its parent library block. For more information, see Disable or Break Links to Library Blocks.

Self-Modifiable links

Linked block with the ability to have structural changes in a linked Subsystem block. For more information, see Self-Modifiable Linked Subsystems.

Parameterized links

Created when the parameter values of a linked block are modified through MATLAB® command prompt. For more information, see Parameterized Links and Self-Modifiable Linked Subsystems.

Forwarding Tables

Maps old library block path to new library block path. For more information, see Forwarding Tables.

Transformation function

Corrects the mismatch of parameters in the InstanceData of the new and old library links thus ensuring that the library links continue to work. For more information, see Transformation Functions.

See Also

Related Topics

Was this topic helpful?