Simulink.connectBlocks

Connect blocks with signal lines

Since R2024b

Syntax

connection = Simulink.connectBlocks(src,dst)

connection = Simulink.connectBlocks(src,dst,RoutingStyle=Value)

Description

connection = Simulink.connectBlocks(src,dst) connects the source specified by src to the destination specified by dst with signal lines. The source and destination can be on different levels of the model hierarchy. When you programmatically connect blocks inside a Variant Subsystem block, the connection is only made in the active variant.

When the model is open, you can undo the connection by pressing Ctrl+Z (on macOS, press command+Z).

connection = Simulink.connectBlocks(src,dst,RoutingStyle=Value) makes the connection and arranges the signals according to the routing style you specify as a value for RoutingStyle.

Examples

Connect Blocks Without Specifying Ports

Open the model named ConnectBlocksWithoutSpecifyingPorts.slx by entering this command in the MATLAB® Command Window. The model contains an unconnected Sine Wave block named Input Signal and an unconnected Subsystem block named Plant. The subsystem contains an unconnected Scope block named Scope1.

model = "ConnectBlocksWithoutSpecifyingPorts";
open_system(model);

Connect the blocks named Input Signal and Scope1.

1. Specify the block paths of the source and destination blocks.

src = model+"/Input Signal";
dst = model+"/Plant/Scope1";

Alternatively, specify which blocks to connect using block handles.

srcPath = model+"/Input Signal";
dstPath = model+"/Plant/Scope1";

src = getSimulinkBlockHandle(srcPath);
dst = getSimulinkBlockHandle(dstPath);

2. Connect the blocks.

connection = Simulink.connectBlocks(src,dst);

Connect Specific Block Ports

Open the model named ConnectSpecificBlockPorts.slx by entering this command in the MATLAB® Command Window. The model includes a Bus Selector block named Bus Selector with two unconnected output ports and an unconnected Subsystem block named Plant. The Subsystem block named Plant contains an unconnected Scope block named Scope1 with three unconnected input ports.

model = "ConnectSpecificBlockPorts";
open_system(model);

If you connect the block named Bus Selector to the block named Scope1 using the Simulink.connectBlocks function and you only specify which blocks to connect, not which ports, the function connects the top output port of the block named Bus Selector to the top input port of the block named Scope1. To connect the two blocks at different ports, you must specify which ports you want to connect. In this example, you connect the bottom port of the block named Bus Selector to the bottom port of the block named Scope1.

1. Specify the port paths of the source and destination blocks.

src = model+"/Bus Selector/2";
dst = model+"/Plant/Scope1/3";

Alternatively, specify which ports to connect using port handles.

srcBlockPath = model+"/Bus Selector";
srcBlockPortHandles = get_param(srcBlockPath,"PortHandles");
src = srcBlockPortHandles.Outport(2);

dstBlockPath = model+"/Plant/Scope1";
dstBlockPortHandles = get_param(dstBlockPath,"PortHandles");
dst = dstBlockPortHandles.Inport(3);

2. Connect the blocks.

connection = Simulink.connectBlocks(src,dst);

Connect to Control Input Port of Conditionally Executed Subsystem

Open the model named ConnectToControlInputPort.slx by entering this command in the MATLAB® Command Window. The model contains an unconnected Constant block and an unconnected Triggered Subsystem block.

model = "ConnectToControlInputPort";
open_system(model);

Connect the Constant block to the trigger port of the Triggered Subsystem block.

1. Specify the port paths of the source and destination blocks. Instead of ending with a port number, the path of the trigger port ends with the port name, Trigger.

src = model+"/Constant/1";
dst = model+"/Triggered Subsystem/Trigger";

Alternatively, specify which ports to connect using port handles.

srcBlockPath = model+"/Constant/1";
srcBlockPortHandles = get_param(srcBlockPath,"PortHandles");
src = srcBlockPortHandles.Outport(1);

blockPath = model+"/Triggered Subsystem";
blockPortHandles = get_param(blockPath,"PortHandles");
dst = blockPortHandles.Trigger;

2. Connect the blocks.

connection = Simulink.connectBlocks(src,dst);

Connect Blocks with Specific Routing Style

Open the model named ConnectBlocksWithSpecificRoutingStyle.slx by entering this command in the MATLAB® Command Window. The model contains an unconnected Sine Wave block named Input Signal and an unconnected Subsystem block named Plant. The subsystem contains an unconnected Scope block named Scope1.

model = "ConnectBlocksWithSpecificRoutingStyle";
open_system(model);

Connect the blocks named Input Signal and Scope1 with smart automatic line routing turned off.

1. Specify the source and destination of the connection.

src = model+"/Input Signal";
dst = model+"/Plant/Scope1";

2. Connect the blocks. Set the value of RoutingStyle to Simulink.Connection.RoutingStyle.Direct.

connection = Simulink.connectBlocks(src,dst,...
    RoutingStyle=Simulink.Connection.RoutingStyle.Direct);

Get Types, Handles, and Paths of Model Elements Created by Simulink.connectBlocks Function

Open the model named GetNameHandleTypeofConnection.slx by entering this command in the MATLAB® Command Window. The model contains an unconnected Sine Wave block named Input Signal and an unconnected Subsystem block named Plant. The subsystem contains an unconnected Scope block named Scope1.

model = "GetNameHandleTypeofConnection";
open_system(model);

Connect the blocks named Input Signal and Scope1 using the Simulink.connectBlocks function.

src = "GetNameHandleTypeofConnection/Input Signal";
dst = "GetNameHandleTypeofConnection/Plant/Scope1";
connection = Simulink.connectBlocks(src,dst);

connection is a Simulink.connectBlocks object that contains an array of objects representing the model elements the Simulink.connectBlocks function creates to connect the blocks.

Get the array of objects.

transits = connection.getTransits;

Get Type, Handle, and Path of One Model Element

To get the type or handle of a model element the Simulink.connectBlocks function creates when making a connection, use dot notation. If the model element is a block, you can also get the block path using dot notation.

For example, to get the type of the model element corresponding to the object in the transits array with index 1, use this command.

type = transits(1).getType

type = 
  Type enumeration

    block

To get the block handle, use this command.

handle = transits(1).getHandle

handle = 
282.0054

To get the block path, use this command.

path = transits(1).getName

path = 
'GetNameHandleTypeofConnection/Plant/Input Signal'

Get Types and Handles of All Model Elements

To get the types of all model elements the Simulink.connectBlocks function creates when making a connection, use this command.

types = arrayfun(@(x)x.getType,transits)

types = 
  3×1 Type enumeration array

    block
    line 
    line 

The arrayfun function executes the command specified in the first input argument for every element of the array specified in the second input argument. In the command, the array element is represented by the variable specified in the format @(name). In this example, the array element is represented by the variable x. For each transits array element, x, the arrayfun function executes x.getType(). That is, for every object in the transits array, the arrayfun function outputs the object type.

To get the handles of all model elements the Simulink.connectBlocks function created when making a connection, use this command.

handles = arrayfun(@(x)x.getHandle,transits)

handles = 3×1

  282.0054
  285.0067
  286.0079

Get Handles of Model Elements of Specific Type

You can also use the arrayfun function to get the handles of all model elements of a specific type the Simulink.connectBlocks function creates when making a connection.

For example, get the handles of all the signal lines represented by the objects in the transits array.

First, determine which objects in the transits array are signal lines using this command.

isLine = arrayfun(@(x)x.getType=="line",transits)

isLine = 3×1 logical array

   0
   1
   1

The arrayfun function executes the command specified in the first input argument for every element of the array specified in the second input argument. In the command, the array element is represented by the variable specified in the format @(name). In this example, the array element is represented by the variable x. For each transits array element, x, the arrayfun function executes x.getType()=="line". That is, for every object in the transits array, the arrayfun function outputs 1 if the object represents a signal line or 0 if the object does not represent a signal line.

Store the objects in the transits array that represent signal lines in an array.

lineTransits = transits(isLine);

Get the handles of the objects in the transits array that represent signal lines.

h = arrayfun(@(x)x.getHandle,lineTransits)

h = 2×1

  285.0067
  286.0079

For each lineTransits element, x, the arrayfun function executes x.getHandle. That is, for every object in the lineTransits array, the arrayfun function outputs the handle.

Get Block Paths

You can use a similar approach to get the block paths of all blocks the Simulink.connectBlocks function creates when making a connection.

isBlock = arrayfun(@(x)x.getType=="block",transits);
blockTransits = transits(isBlock);
paths = arrayfun(@(x)x.getName,blockTransits,UniformOutput=false)

paths = 1×1 cell array
    {'GetNameHandleTypeofConnection/Plant/Input Signal'}

The output of the last command might be nonscalar. Set UniformOutput to false to support nonscalar outputs.

To convert the output to a string array, use this command.

paths = string(paths)

paths = 
"GetNameHandleTypeofConnection/Plant/Input Signal"

Input Arguments

src — Source of signal line

port handle | port path | block handle | block path

Source of the signal line you want to create, specified as a block or output port using a handle or path. If the specified destination is a block, the specified source must be a block. If the specified destination is a port, the specified source must be a port. If you specify the source and destination as blocks, the function connects an unconnected port on the source block to an unconnected port on the destination block. If the source you specify (block or port) is fully connected, the function branches one of the signal lines connected to the source.

For information about how to get the handle or path of a block or port, see Get Handles and Paths. Specify block and port handles as scalars. Specify block and port paths as strings or character vectors. Typically, the port path is the block path followed by a slash and the port number, for example, "myModel/mysubSystem/myBlock/1". Using a port path to specify a subsystem port whose name has been changed from the default port number is not supported. Use a handle instead.

If the source is the state port of an Integrator block, the port path ends with the port name State instead of a port number, for example, "myModel/mysubSystem/myBlock/State".

To connect to a state port, the state port must be visible. By default, the state port on the Integrator block is hidden. To make the port visible, run this command, where path is the block path of the Integrator block.

set_param(path,ShowStatePort="on")

Example: "myModel/myBlock"

Example: "myModel/mysubSystem/myBlock/1"

dst — Destination of signal line

port handle | port path | block handle | block path

Destination of the signal line you want to create, specified as a block or input port using a handle or path. If the specified source is a block, the specified destination must be a block. If the specified source is a port, the specified destination must be a port. If you specify the source and destination as blocks, the function connects an unconnected port on the source block to an unconnected port on the destination block. If the specified destination is a block, the block must have at least one unconnected port. If the specified destination is a port, the port must be unconnected.

For information about how to get the handle or path of a block or port, see Get Handles and Paths. Specify block and port handles as scalars. Specify block and port paths as strings or character vectors. Typically, the port path is the block path followed by a slash and the port number, for example, "myModel/mysubSystem/myBlock/1". Using a port path to specify a subsystem port whose name has been changed from the default port number is not supported. Use a handle instead.

If the destination is the control input port of a conditionally executed subsystem, the port path ends with the port name of the port instead of a port number, for example, "myModel/mysubSystem/myBlock/Trigger". The table lists the port names of the control input ports of conditionally executed subsystems.

Conditionally Executed Subsystem	Port Name
Triggered	Trigger
Enabled	Enable
Enabled and Triggered	Trigger Enable
Resettable	Reset
If Action	Ifaction
Switch Case Action	Ifaction
Function-Call	Trigger
Message Polling	Trigger
Message Triggered	Trigger

The initial condition (IC) port of a While Iterator block has a port number, but the port number is not visible on the block. By default, the port number is 2.

Example: "myModel/myBlock"

Example: "myModel/mysubSystem/myBlock/1"

Example: "myModel/mysubSystem/myBlock/Trigger"

RoutingStyle — Style of signal line layout

Simulink.Connection.RoutingStyle.Orthogonal (default) | Simulink.Connection.RoutingStyle.Direct

Style of signal line layout, specified as Simulink.Connection.RoutingStyle.Orthogonal or Simulink.Connection.RoutingStyle.Direct. By default, the Simulink.connectBlocks function uses smart automatic line routing. The signal lines the function creates are composed exclusively of orthogonal line segments and avoid overlapping other blocks and signal lines.

To turn smart automatic line routing off and create signal lines that connect blocks using the most direct route without avoiding overlap, specify the input argument RoutingStyle with the value Simulink.Connection.RoutingStyle.Direct.

To turn smart automatic line routing on, specify the input argument RoutingStyle with the value Simulink.Connection.RoutingStyle.Orthogonal.

Example: RoutingStyle=Simulink.Connection.RoutingStyle.Direct

Output Arguments

connection — Model elements function creates to connect blocks

Simulink.connectBlocks object

Model elements function creates to connect blocks, returned as a Simulink.connectBlocks object that contains an array of objects corresponding to the model elements. The model elements can be signal lines and blocks. For example, when connecting a block at the top level of the model to a block in a subsystem, the function creates an Inport block in the subsystem.

To get the array of objects from the Simulink.connectBlocks object, use this command.

transit = connection.getTransit

Use these commands to get the type and handle of the model element corresponding to the object in the transit array with index i. If the model element is a block, you can also get the block path.

Attribute	Command
Type	t(i).getType
Handle	t(i).getHandle
Block path	t(i).getName

Version History

Introduced in R2024b

R2025a: Get block paths and port paths using context menu

Starting in R2025a, you can get a block or port path from the context menu. Right-click the block or port and select Copy Path. When you paste the path into a command, remember to add quotes to convert the path into a string or a character vector. For more information about getting and using paths, see Get Handles and Paths.