Check Box

Select parameter or variable value

• 

Libraries:
Simulink / Dashboard

Description

The Check Box block allows you to set the value of a parameter or variable during simulation by checking or clearing the box. Use the Check Box block with other Dashboard blocks to create an interactive dashboard for your model.

Double-clicking the Check Box block does not open its dialog box during simulation and when the block is selected. To edit the block's parameters, you can use the Property Inspector, or you can right-click the block and select Block Parameters from the context menu.

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, in the canvas, select the dashboard block to connect. On the Simulink^® Toolstrip, a tab named after the type of the selected block appears. 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.

Examples

Interactively Simulate a Vehicle Climate Control System

Use a dashboard of controls and indicators to interact with the simulation of an automobile climate control system.

Open Model

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

Connection

Connection — Select a variable or block parameter to connect

variable and parameter connection options

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: []

Main

Check Box Label — Description of check box action

Label (default) | character vector

Label that appears next to the check box. You can use the Check Box Label to describe what happens in your model when you check the check box.

Example: Enable sound

Programmatic Use

Block Parameter: Label

Type: character vector

Default: 'Label'

Checked/Unchecked Values — Values to assign for checked and unchecked states

Unchecked: 0 Checked: 1 (default) | scalar

Value to assign to the connected variable or parameter for the checked and unchecked block states.

• Unchecked — Value assigned to the connected parameter when the Check Box block is not checked.

• Checked — Value assigned to the connected parameter when the Check Box block is checked.

Programmatic Use

You set the Unchecked and Checked values programmatically using a 2-by-1 vector that contains the Unchecked and Checked values, in that order.

Block Parameter: Values

Type: 2x1 vector

Default: [0 1]

Label — Block label position

Hide (default) | Bottom | Top

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'

Format

Opacity — Block background opacity

1 (default) | scalar

Block background opacity, specified as a scalar value between 0 and 1.

Example: 0.5

Programmatic Use

Block Parameter: Opacity

Type: scalar

Default: 1

Foreground Color — Block foreground color

[r g b] vector

Block foreground color, including the text. You can select a color from a palette of standard colors or specify a custom color.

Programmatic Use

Specify the ForegroundColor parameter for the block as a string or a character vector that defines a 1-by-3 [r g b] vector with values between 0 and 1.

Block Parameter: ForegroundColor

Type: character vector | string

Values: [r g b] vector

Background Color — Block background color

[r g b] vector

Block background color. You can select a color from a palette of standard colors or specify a custom color.

Programmatic Use

Specify the BackgroundColor parameter for the block as a string or a character vector that defines a 1-by-3 [r g b] vector with values between 0 and 1.

Block Parameter: BackgroundColor

Type: character vector | string

Values: [r g b] vector

Block Characteristics

Data Types	double | half | integer | single
Direct Feedthrough	no
Multidimensional Signals	no
Variable-Size Signals	no
Zero-Crossing Detection	no

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using Simulink® Coder™.

Dashboard blocks are ignored for code generation.

Version History

Introduced in R2017b

R2021a: Tune matrix and structure elements using dashboard blocks

Starting in R2021a, you can connect a block from the Dashboard library to a scalar element of a matrix or structure that defines the value of a tunable block parameter. When you connect a dashboard block to a tunable parameter, you first select one or more blocks. Then, in a dialog box, you select the parameter to which you want to connect. When you select a parameter that has a nonscalar value, specify the element you want to tune using the text box in the dialog box.

R2020b: Background Color, Foreground Color, and Opacity properties added for several dashboard blocks

Starting in R2020b, you can specify a background color, a foreground color, and opacity for these blocks from the Dashboard library:

• Check Box

• Combo Box

• Edit

• Push Button

• Radio Button

R2020b: Simulink Toolstrip support for dashboard blocks

Starting in R2020b, the Block tab in the Simulink Toolstrip turns into a block-specific tab when you select a block in your model that is from the Dashboard library in the Simulink library or from the Flight Instruments library in the Aerospace Blockset™ Flight Control Analysis library. From the toolstrip, you can connect, disconnect, and modify connections for the selected block. You can jump to the model element connected to the selected block, and you can add the selected block to a panel.

R2019a: Programmatically add and configure dashboard blocks

Starting in R2019a, you can use functions such as add_block and set_param to create and configure blocks from the Dashboard library in your model.