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Push Button

Change parameter or variable value using button with customizable appearance

  • Library:
  • Simulink / Dashboard / Customizable Blocks

  • Push Button block.

Description

Use the Push Button block to change the value of the connected variable or parameter before or during simulation. You can configure the button to change the value only while you press the button or to latch the value change until you click the button again. When you use the Push Button block in the Customizable Blocks library, you can modify the appearance of the block so it looks like a button in your real system. Use the Push Button block with other Dashboard blocks to create an interactive dashboard to control your model.

Double-clicking the Push Button block does not open its dialog box during simulation or when the block is selected. To edit the block parameters, you can use the Property Inspector or open the block dialog box by:

  • Double-clicking the block when the block is not selected and the model is not simulating.

  • Right-clicking the block and selecting Block Parameters from the context menu.

Customize Push Button Blocks

When you add a Push Button block to your model, the block is preconfigured with a default design. You can use the block with the default design or customize the appearance of the block. When you design a Push Button block, you configure the block appearance for each possible state. When you configure the Block Type as Momentary, the block has two states, and when you configure the Block Type as Latch, the block has four. For each state, you can:

  • Add an image to define the appearance of the block in that state.

  • Specify text for the button label and configure its color and position within the block.

  • Add an icon and specify the position of the icon relative to the label.

When you want an aspect of the block, such as the label text or color, to indicate the state of the block, configure that aspect of the design differently for each state. When you want an aspect of the block to remain the same for all states, configure that aspect of the block design so it is the same for all states.

You can also design the block background and foreground, which apply for all states. To configure the foreground for the block, upload a foreground image. To configure the background for the block, you can upload a background image or use a solid background color.

To customize the appearance of the block, use design mode. You can enter design mode in one of three ways after selecting the block:

  • On the Button tab, under Design, click Edit.

  • In the Property Inspector, on the Design tab, click Edit Design.

  • Pause on the ellipsis that appears above the block and click the Edit Custom Block button.

Design mode gives you access to block parameters and settings that allow you to customize the appearance of the block. You can use the toolbar above the block to configure the image, the icon, and the label color and opacity for each state. For more customization options, use the Design tab in the Property Inspector.

Push Button block in design mode with the toolbar and the Design tab in the Property Inspector visible.

When you finish designing the button, click Exit in the upper-right of the canvas to exit design mode.

Connect Dashboard Blocks

Dashboard blocks do not use ports to connect to model elements. To connect dashboard blocks to variables and block parameters, use connect mode. Connect mode facilitates the process of connecting dashboard blocks in your model, especially when you want to connect multiple blocks at once. To connect a single dashboard block, you can also use the Connection table in the block dialog box.

Tip

You can modify dashboard block connections in your model during normal and accelerator mode simulations.

Note

Dashboard blocks cannot connect to variables until you update the model diagram. To connect dashboard blocks to variables or modify variable values between opening your model and running a simulation, update the model diagram using Ctrl+D.

To enter connect mode, select the block. Then, on the block tab, click Connect. In connect mode, when you select one or more blocks, a list of parameters and variables available for connection appears. Select a variable or parameter from the list to connect to the selected dashboard block.

When the value of the selected variable or block parameter is nonscalar, use the text box at the bottom of the Connection table to specify the element you want to connect to the dashboard block. To connect to an element of a vector, matrix, or array, specify the element index, for example, 3 or (1,3). To connect to an element in a bus or structure, specify the element in the context of the bus or structure hierarchy by using dots to indicate different levels in the hierarchy, and omit the top level. For example, specify a.b to connect to scalar element b of the structure or bus a nested inside the selected composite variable or parameter.

To connect another dashboard block, pause on another dashboard block and click the Connect button above it. Then, make a selection of signals and blocks in your model and choose a model element to connect.

When you finish connecting the dashboard blocks in your model, on the block tab, click Done Connecting.

Tip

You can hide the message shown on unconnected blocks using the set_param function with the ShowInitialText block parameter. The message also disappears when you connect the block.

Parameter Logging

Tunable parameters connected to dashboard blocks are logged to the Simulation Data Inspector, where you can view the parameter values along with logged signal data. You can access logged parameter data in the MATLAB® workspace by exporting the parameter data from the Simulation Data Inspector by using the UI or the Simulink.sdi.exportRun function. For more information about exporting data using the Simulation Data Inspector UI, see Export Data to the Workspace or a File. The parameter data is stored in a Simulink.SimulationData.Parameter object, accessible as an element in the exported Simulink.SimulationData.Dataset.

Limitations

  • Except for the Dashboard Scope block and the Display block, dashboard blocks can only connect to real scalar signals.

  • The toolstrip does not support blocks that are inside a panel.

  • You cannot use the Connection table in the block dialog to connect a dashboard block to a block that is commented out. When you connect a dashboard block to a commented block using connect mode, the dashboard block does not display the connected value until the you uncomment the block.

  • Dashboard blocks cannot connect to model elements inside referenced models.

  • When you simulate a model hierarchy, dashboard blocks inside referenced models do not update.

  • Dashboard blocks do not support rapid accelerator simulation.

  • When you connect a dashboard block to a variable or parameter during simulation, the data for that variable or parameter is not logged to the Simulation Data Inspector. To log variable and parameter data to the Simulation Data Inspector, connect the dashboard block to the variable or parameter prior to simulation.

  • When you simulate a model in external mode with the Default parameter behavior set to Inlined, dashboard blocks can appear to change parameter and variable values. However, the change does not propagate to the simulation. For example, Gain blocks display changes made to the Gain parameter using the dashboard blocks, but the Gain value used in the simulation does not change.

Parameters

expand all

Select the variable or block parameter to control using the Connection table. To connect the block to a signal:

  1. Make a selection in the model that includes one or more blocks.

  2. Select the variable or parameter you want to connect.

    When the value of the selected variable or block parameter is nonscalar, use the text box at the bottom of the Connection table to specify the element you want to connect to the dashboard block. To connect to an element of a vector, matrix, or array, specify the element index, for example, 3 or (1,3). To connect to an element in a bus or structure, specify the element in the context of the bus or structure hierarchy by using dots to indicate different levels in the hierarchy, and omit the top level. For example, specify a.b to connect to scalar element b of the structure or bus a nested inside the selected composite variable or parameter.

  3. Click Apply.

To facilitate understanding and debugging your model, you can connect Dashboard blocks to variables and parameters in your model during simulation.

Note

To see workspace variables in the connection table, update the model diagram using Ctrl+D.

Programmatic Use

To programmatically connect a dashboard block to a tunable parameter or a variable, use a Simulink.HMI.ParamSourceInfo object. The Simulink.HMI.ParamSourceInfo object contains four properties. Some of the properties apply to connecting dashboard blocks to parameters, and some apply to connecting dashboard blocks to variables. Not all fields have a value for a connection because a given dashboard block connects to either a parameter or a variable.

Block Parameter: Binding
Type: Simulink.HMI.ParamSourceInfo
Default: []

Specify how the block responds to a click.

  • Momentary — The button changes state only while pressed. When you release the mouse, the button returns to its default state.

  • Latch — The button latches the state change when clicked. The button remains in the pressed state until you click it again.

When you configure Button Type as Momentary, the block has these states:

  • Default — Default state for the block when it is not pressed

  • Pressed — Block state when the block is pressed

When you configure Button Type as Latch, the block has these states:

  • Default — Default state for the block when it is not pressed.

  • Pressed — Transitional state when you press the button while it is in the Default state. The block transitions to the Latched state when you release the mouse.

  • Latched — Latched state for the block when it is not pressed.

  • Latched and Pressed — Transitional state when you press the button while it is in the Latched state. The block transitions to the Default state when you release the mouse.

The value assigned to the connected block parameter when the button is pressed or latched.

Tips

Use the Block Type parameter to configure how the block responds to a click:

  • Momentary — The button applies the On Value only while you press it.

  • Latch — The button latches the state change when you click it and applies the On value until you click it again.

Programmatic Use

Block Parameter: OnValue
Type: string or character array
Default: '1'

Position of the block label. When the block is connected to an element in the model, the label is the name of the connected element.

Programmatic Use

Block Parameter: LabelPosition
Type: character vector
Values: 'Hide' | 'Bottom' | 'Top'
Default: 'Hide'

Whether to maintain the block aspect ratio when resizing the block and when you specify a new background image.

Block Characteristics

Data Types

double | half | integer | single

Direct Feedthrough

no

Multidimensional Signals

no

Variable-Size Signals

no

Zero-Crossing Detection

no

Extended Capabilities

Introduced in R2021b