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Connection Port

Physical Modeling connector port for subsystem

  • Library:
  • Simulink / Signal Routing

    Simscape / Utilities

    Powertrain Blockset / Utilities / Simscape

    RF Blockset / Equivalent Baseband / Input

    RF Blockset / Circuit Envelope / Utilities

    Vehicle Dynamics Blockset / Utilities / Simscape

  • Connection Port block

Description

The Connection Port block transfers a physical connection or signal across subsystem boundaries. Physical connections include Simscape™ conserving and physical signal connections, Simscape Multibody™ connections, and Vehicle Dynamics Blockset™ two-way connection ports, among others. This block is similar in function to the Inport and Outport blocks in the Simulink® library.

A subsystem needs a Connection Port block for each physical connection line that crosses its boundary. You can manually place a Connection Port block inside a subsystem, or Simulink can automatically insert a Connection Port block when you create a subsystem within an existing network.

Port Appearance on Subsystem Block

The Connection Port block adds a port to the parent Subsystem block. The port type depends on the connection or signal it transfers. The port appearance on the Subsystem block matches the port to which the Connection Port block connects inside the subsystem. For example, if the port transfers a Simscape conserving connection, then it appears on the Subsystem block as a Simscape conserving port.

Consider a subsystem with Simulink input and output ports labeled In and Out, respectively. If you place a Connection Port block inside this subsystem and leave it unconnected, the connection port on the parent Subsystem block appears as a white circle.

Block diagram with Connection Port block added to subsystem

Appearance of connection port on subsystem icon

However, if you connect the Connection Port block to a Mass block, the appearance of the connection port on the parent Subsystem block changes to a conserving port.

Block diagram with Connection Port block connected to Mass block

Changed appearance of connection port on subsystem icon

The connection port becomes typed as mechanical translational, that is, you can connect only mechanical translational ports on other blocks to this subsystem port.

Port Naming and Location on Subsystem Block

Similar to the Simulink input and output ports, the connection port on the subsystem icon displays the port number instead of the block name when the port block has the default name. If you add a Connection Port block with default name and parameters to a subsystem, the connection port is labeled with the Port number parameter value and located on the left side of the parent Subsystem block icon.

Connection port appears on the left side of subsystem icon

To switch the port to display on the right side of the icon, change the Port location on the parent subsystem parameter value to Right.

Connection port appears on the right side of subsystem icon

Flexible port placement in Simulink Editor lets you move ports by clicking and dragging the port along the block icon outline, and this way you can put ports on any side of a Subsystem block, including top and bottom. The Port location on the parent subsystem parameter does not have separate values for top or bottom. If you drag a port to a different location on the Subsystem block icon, the parameter value automatically changes to reflect the new placement:

  • Left — The port appears on the left or top side of the subsystem icon.

  • Right — The port appears on the right or bottom side of the subsystem icon.

If there are multiple connection ports, the port index is automatically renumbered after each move, as necessary, to reflect the new port location. For example, if a Subsystem block has three connection ports, as shown, and you move port 2 to the bottom of the block icon, ports 2 and 3 are renumbered. The value of the Port number parameter of these two Connection Port blocks automatically changes to match the new port number.

Connection ports renumbered according to location on the subsystem block icon

The orientation of the parent Subsystem block can also affect the port location. For example, if you flip the parent Subsystem block, the connection port 1 appears on the opposite side to what its Port location on the parent subsystem parameter indicates.

Connection port side flips when the subsystem block is flipped

Specifying Rigid Interfaces

You can lock down the connection type for the block port by applying a rigid interface specification. For example, you can restrict the block to accept connections only from the mechanical translational ports on other blocks. For a list of Foundation domain types, see Domain-Specific Line Styles. If you apply a rigid interface using a ConnectionBus object, the Connection Port block can be connected only to a bus port of a Simscape Bus block.

Use the Connection type parameter to specify a rigid interface, such as a particular domain type or a ConnectionBus object. When you apply a rigid interface definition, the block appearance changes, as shown:

  1. Flexible connection

  2. Rigid domain connection

  3. Rigid bus connection

Connection port block appearance in model diagrams for different connection types

To remove the rigid interface specification, set the Connection type parameter to Inherit: auto.

Ports

Conserving

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Physical modeling connection port. By default, this port is untyped.

You define the type of the port by connecting it to a conserving port or a physical signal port of another block, or to a Simscape Bus port. Once you establish a connection, the port appearance on the parent Subsystem block changes accordingly, the port becomes typed and can be connected only to the same type of port.

Parameters

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Labels the subsystem connector port that this block creates. Each connector port requires a unique number as a label. If you do not mask the parent subsystem and use the default block name, the value of this parameter appears as a label next to the corresponding port on the parent Subsystem block icon. If you change the name of the Connection Port block, then the block name appears as a label next to the corresponding port on the parent Subsystem block icon. You can also use masking to change the subsystem port names. For more information, see Masking Fundamentals.

The default value for the first port is 1. As you create more ports, the software labels them incrementally. If you move the ports to a different location on the Subsystem block icon, the Simulink Editor may renumber the ports, according to its rules. In this case, the value of the Port number parameter of the corresponding Connection Port block automatically changes to match the new port number.

Choose which side of the parent subsystem block the port is located: Left or Right. If you move the port to a different location on the Subsystem block icon, the parameter value automatically changes to reflect the new placement. For more information, see Port Naming and Location on Subsystem Block.

Specify a rigid interface by selecting a port type from the drop-down list. The list contains the names of Foundation domains and ConnectionBus objects present in the base workspace or a data dictionary. For more granularity, click the Show type assistant button next to the drop-down list to display the Type Assistant panel.

For more information, see Specifying Rigid Interfaces.

To remove the rigid interface specification, set the Connection type parameter to Inherit: auto.

Works in conjunction with the Connection type parameter and provides additional options for specifying a rigid interface:

  • Inherit — Indicates flexible interface. The only drop-down option available is auto. Corresponds to the Connection type parameter setting Inherit: auto.

  • Connection Bus object — Specify a rigid bus connection. Type the name of an existing ConnectionBus object in the <object name> field or use the Edit button to open the Bus Editor and create or modify a ConnectionBus object. In this case, the Connection Port block can be connected only to a bus (bundle) port of a Simscape Bus block.

  • Connection — Specify a rigid connection type by selecting a domain name from the drop-down list. The Simscape Domains link at the bottom of the dialog box lets you view the list of Foundation domain names and domain-specific line styles.

Dependencies

To enable this selection, click the Show type assistant button next to the Connection type parameter. As you select values in the Type Assistant panel, the Connection type parameter setting updates accordingly.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Introduced in R2007a