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Floating Scope and Scope Viewer

Display signals generated during simulation without signal lines

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  • Scope Viewer block

Libraries:
Simulink / Sinks
HDL Coder / Sinks

Description

The Simulink® Scope Viewer and Floating Scope block display time domain signals with respect to simulation time. The Scope Viewer and Floating Scope block have the same functionality as the Scope block, but they are not connected to signal lines.

For information on controlling a Floating Scope block from the command line, see Control Scope Blocks Programmatically in the Simulink documentation.

Connect Signals

In the Floating Scope window or Scope viewer window, use the button to connect signals.

To add a viewer with a connected signal, select a signal in the model. Then, on the Simulation tab, in the Prepare gallery, click Add Viewer.

For more details, see Add Signals to an Existing Floating Scope or Scope Viewer.

Key Features

  • Multiple y-axes (displays) — Display multiple y-axes with multiple input ports. All the y-axes have a common time range on the x-axis.

  • Multiple signals — Show multiple signals on the same y-axis (display) from one or more input ports.

  • Modify parameters — Modify scope parameter values before and during a simulation.

  • Display data after simulation — If a scope is closed at the start of a simulation, scope data is still written to the scope during the simulation. If you open the scope after a simulation, the scope displays simulation results for input signals.

Oscilloscope Measurements

  • Triggers — Set triggers on repeating signals and pause the display when events occur.

  • Cursor Measurements — Measure signal values using vertical and horizontal cursors.

  • Signal Statistics1 — Display the maximum, minimum, peak-to-peak difference, mean, median, and RMS values of a selected signal.

  • Peak Findera — Find maxima, showing the x-axis values at which they occur.

  • Bilevel Measurementsa — Measure transitions, overshoots, undershoots, and cycles.

Examples

Simulation of Bouncing Ball

Simulation of Bouncing Ball

Uses two models of a bouncing ball to show different approaches to modeling hybrid dynamic systems with Zeno behavior. Zeno behavior is informally characterized by an infinite number of events occurring in a finite time interval for certain hybrid systems. As the ball loses energy, the ball collides with the ground in successively smaller intervals of time.

Limitations

When you use model configuration parameters that optimize the simulation, such as Signal storage reuse or Block reduction, Simulink eliminates storage for some signals during simulation. You are unable to apply a Floating Scope to these eliminated signals. To work around this issue, configure an eliminated signal as a test point. You can then apply a Floating Scope to the signal regardless of optimization settings. To configure test points, see Configure Signals as Test Points.

  • If you step back the simulation after adding or removing a signal, the Floating Scope clears the existing data. New data does not appear until the simulation steps forward again.

  • When connected to a constant signal, the scope plots a single point.

  • Simulink messages are not supported for Floating Scope block and Scope Viewer.

  • You cannot connect signals from for-each subsystems.

  • Scope displays have limitations in Rapid Accelerator mode. See Behavior of Scopes and Viewers with Rapid Accelerator Mode

Ports

Input

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Connect the signals you want to visualize. You can have up to 96 input ports. Input signals can have these characteristics:

  • Type — Continuous (sample-based) or discrete (sample-based and frame-based).

  • Data type — Any data type that Simulink supports. See Data Types Supported by Simulink.

    This block accepts fixed-point input, but converts it to double for display.

  • Dimension — Scalar, one dimensional (vector), two dimensional (matrix), or multidimensional (array). Display multiple channels within one signal depending on the dimension. See Signal Dimensions and Determine Signal Dimensions.

Input Limitations

  • When the input is a constant signal, the scope plots a single point.

  • The scope shows gaps in the display when the signal value is NaN.

  • When you visualize multiple frame-based signals in the scope, some samples of signals with a frame size of 1 might not be displayed. To visualize these signals, move the signals with frame size of 1 to a separate scope.

Bus Support

You can connect nonvirtual bus and arrays of bus signals to a scope. To display the bus signals, use normal or accelerator simulation mode. The scope displays each bus element signal in the order the elements appear in the bus, from the top to the bottom. Nested bus elements are flattened.

To log nonvirtual bus signals with a scope, set the Save format parameter to Dataset. You can use any Save format to log virtual bus signals.

Data Types: single | double | half | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | Boolean | fixed point | enumerated | bus
Complex Number Support: Yes

Properties

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Configuration Properties

The Configuration Properties dialog box controls various properties about the scope displays. From the scope menu, select View > Configuration Properties.

Main

Select this check box to open the scope window when simulation starts.

Programmatic Use

See OpenAtSimulationStart.

Select this check box to display the block path in addition to the block name.

Specify number and arrangement of displays. To expand the layout grid beyond 4 by 4, click within the dialog box and drag. The maximum layout is 16 rows by 16 columns.

If the number of displays is equal to the number of ports, signals from each port appear on separate displays. If the number of displays is less than the number of ports, signals from additional ports appear on the last display. For layouts with multiple columns and rows, ports are mapped down and then across.

Programmatic Use

See LayoutDimensions.

  • Elements as channels (sample based) — Process each element as a unique sample.

  • Columns as channels (frame based) — Process signal values in a column as a group of values from multiple time intervals. Frame-based processing is available only with discrete input signals.

Programmatic Use

See FrameBasedProcessing.

  • Auto — If Title and Y-label properties are not specified, maximize all plots.

  • On — Maximize all plots. Values in Title and Y-label are hidden.

  • Off — Do not maximize plots.

Programmatic Use

See MaximizeAxes.

Time

  • Auto — Difference between the simulation start and stop times.

    The block calculates the beginning and end times of the time range using the Time display offset and Time span properties. For example, if you set the Time display offset to 10 and the Time span to 20, the scope sets the time range from 10 to 30.

  • User defined — Enter any value less than the total simulation time.

  • One frame period — Use the frame period of the input signal to the Time Scope block. This option is only available when the Input processing parameter is set to Columns as channels (frame based).

Programmatic Use

See TimeSpan.

Specify how to display data beyond the visible x-axis range.

You can see the effects of this option only when plotting is slow with large models or small step sizes.

  • Wrap — Draw a full screen of data from left to right, clear the screen, and then restart drawing the data from the left.

  • Scroll — Move data to the left as new data is drawn on the right. This mode is graphically intensive and can affect run-time performance.

Programmatic Use

See TimeSpanOverrunAction.

  • Metric — Display time units based on the length of Time span.

  • Seconds — Display time in seconds.

  • None — Do not display time units.

Programmatic Use

See TimeUnits.

Offset the x-axis by a specified time value, specified as a real number or vector of real numbers.

For input signals with multiple channels, you can enter a scalar or vector:

  • Scalar — Offset all channels of an input signal by the same time value.

  • Vector — Independently offset the channels.

Programmatic Use

See TimeDisplayOffset.

Specify how x-axis (time) labels display:

  • All — Display x-axis labels on all y-axes.

  • None — Do not display labels. Selecting None also clears the Show time-axis label check box.

  • Bottom displays only — Display x-axis label on the bottom y-axis.

Dependencies

To enable this property, set:

The Active display property determines which display is affected.

Programmatic Use

See TimeAxisLabels.

Select this check box to show the x-axis label for the active display

Dependencies

To enable this property, set Time-axis labels to All or Bottom Displays Only.

The Active display property determines which display is affected.

Programmatic Use

See ShowTimeAxisLabel.

Display

Selected display. Use this property to control which display is changed when changing style properties and axes-specific properties.

Specify the desired display using a positive integer that corresponds to the column-wise placement index. For layouts with multiple columns and rows, display numbers are mapped down and then across.

Programmatic Use

See ActiveDisplay.

Title for a display. The default value %<SignalLabel> uses the input signal name for the title.

Dependency

The Active display property determines which display is affected.

Programmatic Use

See Title.

Toggle signal legend. The names listed in the legend are the signal names from the model. For signals with multiple channels, a channel index is appended after the signal name. Continuous signals have straight lines before their names, and discrete signals have step-shaped lines.

From the legend, you can control which signals are visible. This control is equivalent to changing the visibility in the Style properties. In the scope legend, click a signal name to hide the signal in the scope. To show the signal, click the signal name again. To show only one signal, right-click the signal name, which hides all other signals. To show all signals, press Esc.

Note

The legend only shows the first 20 signals. Any additional signals cannot be controlled from the legend.

Dependency

The Active display property determines which display is affected.

Programmatic Use

See ShowLegend.

Select this check box to show grid lines.

Dependency

The Active display property determines which display is affected.

Programmatic Use

See ShowGrid.

  • On — Display magnitude and phase plots. If the signal is real, plots the absolute value of the signal for the magnitude. The phase is 0 degrees for positive values and 180 degrees for negative values. This feature is useful for complex-valued input signals. If the input is a real-valued signal, selecting this check box returns the absolute value of the signal for the magnitude.

  • Off — Display signal plot. If the signal is complex, plots the real and imaginary parts on the same y-axis.

Dependency

The Active display property determines which display is affected.

Programmatic Use

See PlotAsMagnitudePhase.

Specify the minimum value of the y-axis as a real number.

Tunable: Yes

Dependency

If you select Plot signals as magnitude and phase, this property only applies to the magnitude plot. The y-axis limits of the phase plot are always [-180 180].

The Active display property determines which display is affected.

Programmatic Use

See YLimits.

Specify the maximum value of the y-axis as a real number.

Tunable: Yes

Dependency

If you select Plot signals as magnitude and phase, this property only applies to the magnitude plot. The y-axis limits of the phase plot are always [-180 180].

The Active display property determines which display is affected.

Programmatic Use

See YLimits.

Specify the text to display on the y-axis. To display signal units, add (%<SignalUnits>) to the label. At the beginning of a simulation, Simulink replaces (%SignalUnits) with the units associated with the signals.

Example: For a velocity signal with units of m/s, enter Velocity (%<SignalUnits>).

Dependency

If you select Plot signals as magnitude and phase, this property does not apply. The y-axes are labeled Magnitude and Phase.

The Active display property determines which display is affected.

Programmatic Use

See YLabel.

Logging

Select this property to limit data saved by the scope internally. When you select this property and set the Input processing parameter to:

  • Elements as channels (sample based) –– The scope saves the last n data points and the name of this property is Limit data points to last. n is the scalar value you specify in this property text box.

  • Columns as channels (frame based) –– The scope saves the last n data frames and the name of this property is Limit frames to last.

In some cases, selecting this property can have the effect of plotting signals for less than the entire time range of a simulation (for example if your sample time is small). If the scope plots a portion of your signals, consider increasing the number of data points to save.

When you clear this property, the scope saves all the data. You can visualize the entire data in the scope after the simulation finishes. For simulations with Stop time set to inf, consider selecting this property.

Note

If you do not select this property and you have a high sample rate or long simulation time, you can run into issues with memory or system performance.

Programmatic Use

See DataLoggingLimitDataPoints and DataLoggingMaxPoints.

Select this property to plot and log (save) scope data every Nth data point or frame, where N is the decimation factor you specify in this property text box. A value of 1 buffers all the data values.

When you set the Input processing parameter to:

  • Elements as channels (sample based) –– The scope plots and logs data every Nth data point. The name of this property is Decimation.

  • Columns as channels (frame based) ––- The scope plots and logs data every Nth frame. The name of this property is Decimate frames.

When you clear this property, the scope saves all the scope data.

Programmatic Use

See DataLoggingDecimateData and DataLoggingDecimation.

For signals selected with the Signal Selector, clicking this button toggles the state of the Log signal data check boxes in the Signals Properties dialog boxes.

Axes Scaling Properties

The Axes Scaling Properties dialog controls the axes limits of the scope. To open the Axes Scaling properties, in the scope menu, select Tools > Axes Scaling > Axes Scaling Properties.

  • Manual — Manually scale the y-axis range with the Scale Y-axis Limits toolbar button.

  • Auto — Scale the y-axis range during and after simulation. Selecting this option displays the Do not allow Y-axis limits to shrink check box. If you want the y-axis range to increase and decrease with the maximum value of a signal, set Axes scaling to Auto and clear the Do not allow Y-axis limits to shrink check box.

  • After N Updates — Scale y-axis after the number of time steps specified in the Number of updates text box (10 by default). Scaling occurs only once during each run.

Programmatic Use

See AxesScaling.

Allow y-axis range limits to increase but not decrease during a simulation.

Dependency

To use this property, set Axes scaling to Auto.

Set this property to delay auto scaling the y-axis.

Dependency

To use this property, set Axes scaling to After N Updates.

Programmatic Use

See AxesScalingNumUpdates.

  • On — Scale axes when simulation stops.

  • Off — Scale axes continually.

Dependency

To use this property, set Axes scaling to Auto.

Specify the percentage of the y-axis range used for plotting data. If you set this property to 100, the plotted data uses the entire y-axis range.

Specify where to align plotted data along the y-axis data range when Y-axis Data range is set to less than 100 percent.

  • Top — Align signals with the maximum values of the y-axis range.

  • Center — Center signals between the minimum and maximum values.

  • Bottom — Align signals with the minimum values of the y-axis range.

Scale x-axis range to fit all signal values. If Axes scaling is set to Auto, the data currently within the axes is scaled, not the entire signal in the data buffer.

Specify the percentage of the x-axis range to plot data on. For example, if you set this property to 100, plotted data uses the entire x-axis range.

Specify where to align plotted data along the x-axis data range when X-axis Data range is set to less than 100 percent.

  • Right — Align signals with the maximum values of the x-axis range.

  • Center — Center signals between the minimum and maximum values.

  • Left — Align signals with the minimum values of the x-axis range.

Style Properties

To open the Style dialog box, from the scope menu, select View > Style.

Background color for the scope.

When you select Auto, the plot type is a line graph for continuous signals, a stair-step graph for discrete signals, and a stem graph for Simulink message signals.

Select the background color for axes (displays) with the first color palette. Select the grid and label color with the second color palette.

Specify whether to use the displayed color of the scope when copying.

When you select File > Copy to Clipboard, the software changes the color of the scope to be printer friendly (white background, visible lines). If you want to copy and paste the scope with the colors displayed, select this check box.

Select active line for setting line style properties.

Show or hide a signal on the plot.

Dependency

The values of Active display and Properties for line determine which line is affected.

Select line style, width, and color.

Dependency

The values of Active display and Properties for line determine which line is affected.

Select marker shape.

Dependency

The values of Active display and Properties for line determine which line is affected.

Block Characteristics

Data Types

Boolean | double | enumerated | fixed point | integer | single

Direct Feedthrough

no

Multidimensional Signals

yes

Variable-Size Signals

yes

Zero-Crossing Detection

no

Extended Capabilities

Version History

Introduced in R2015b

See Also

Blocks

Topics

1 You must have a Simscape™ or DSP System Toolbox™ license to use the Peak Finder, Bilevel Measurements, and Signal Statistics.