Generate Waveforms with a Waveform Generator

Use a waveform generator to monitor and configure waveforms in InstrumentStudio.

  1. Add a waveform generator device to the large panel.
  2. Select one of the following waveform modes from the dropdown menu of the device panel:
    • Standard waveform—Generates a waveform using the channel settings that you specify.
    • Arbitrary waveform—Generates a waveform using settings specified in a waveform file and any additional channel settings that you specify.
      Note For more information on waveform modes, see Waveform Modes.
  3. Specify the type of the waveform.
    • For a standard waveform, you can select the waveform type with the Waveform dropdown menu.
      Note If you select a User-defined waveform, you must load a waveform file. User-defined waveform files must be in the .csv format, with the exact number of samples that the Specifications document of your device defines. For example, the PXIe-5433 requires 8192 samples for a user-defined waveform. The waveform samples must be in a single row or a single column.
    • For an arbitrary waveform, you must load a waveform file. Click the … button next to the Filename field to browse for the waveform file. The waveform file specifies the type of waveform to generate.
      Note Arbitrary waveform files can be in the .csv format or a binary format:
    • .csv—For single-channel instruments, waveform samples must be in a single row or a single column. For two-channel instruments, the waveform samples for each channel must be in a separate column.
    • Binary—For single-channel instruments, waveform samples can be 8-byte double-prevision or 2-byte half-precision floating point. The byte order can be little-endian or big-endian. For two-channel instruments, the samples of both channels must be interleaved.
  4. Configure the waveform channel settings directly on the large panel or in the Channel Settings window. To open the Channel Settings window, click on the An icon of three horizontal dots. icon next to the channel. The settings that you can configure change based on the waveform mode and waveform type that you select.
    Note If you generate an arbitrary waveform, you must select a trigger mode for the waveform. To select a trigger mode, complete the following steps:
    1. Click on the An icon of three horizontal dots. icon to open the Channel Settings window.
    2. Scroll down to the Triggers section.
    3. Use the dropdown menu of the Mode setting.
    For more information on arbitrary waveform trigger modes, see Advanced Waveform Sequencing and Triggering on Arbitrary Waveform Generators in the Related Information section.
  5. Select Run.
The waveform generates with the specified settings.

Waveform Modes

You can generate a waveform using one of the following modes:
  • Standard waveform—A standard waveform has the following characteristics:
    • Outputs waveforms according to the channel settings that you specify in InstrumentStudio or an external application.
    • Allows you to generate different waveform types (for example, sine, square, or triangle) at precise frequencies.
    • Allows you to change the output waveform frequency of a standard waveform with a short response time during waveform generation.
    • The Sweep operation mode allows you to configure a range of frequencies to generate over a specified number of steps and a specified time duration.
    • The List operation mode allows you to configure a sequence of frequencies to generate for specified durations.
    Note The User-defined standard waveform type allows you to generate a periodic waveform with a finite, specified number of points. The waveform generation uses Direct Digital Synthesis (DDS). To generate a user-defined waveform of any size, use Arbitrary Waveform mode.
  • Arbitrary waveform—Outputs waveforms according to settings that are specified in an external file. An arbitrary waveform allows you to define large, complex waveforms with a waveform settings file. While you can generate more complex waveforms using an arbitrary waveform, changes to arbitrary waveform settings have a longer response time than standard waveforms.

    • Configure Waveform Channels and Triggers

    You can configure channels, triggers, and other parameters of the waveform generator from the Channel Settings window.

    Click the An icon of three horizontal dots. icon to open the Channel Settings window. You can select the channel that you want to configure on the left side of the window.

    Waveform Channel Settings

    You can configure the following settings in the devicename/channel_number section of the Channel Settings window:
  • Output Impedance—Sets the output impedance value to 50 Ω or 75 Ω.
  • Load Impedance—Sets load impedance to one of the following values:
  • Match output—Matches the load impedance to the output impedance.
  • High-Z—Sets the load impedance to high impedance.
  • Custom—Sets the load impedance to a custom value, in ohms.
  • Digital Filter—Enables or disables the digital filter. The digital filter increases the effective sampling rate by providing points that interpolate between generated samples.
  • Analog Filter—Enables or disables the analog filter. InstrumentStudio applies the analog filter after the interpolated signal. When combined with a digital filter, the combination can remove high-frequency images from the frequency domain.
  • Terminal config.—Returns the terminal configuration for the waveform generator. Most waveform generators support only one option (either Differential or Single-ended).

    • Waveform General Settings

    The settings in the Waveform section of the Channel Settings window correspond to the controls on the panel. The settings that appear in this section depend on the waveform mode and the type of the standard waveform.

    Waveform Trigger Settings

    You can configure the following settings in the Triggers section of the Channel Settings window:
  • Trigger Mode—Sets the mode for triggering arbitrary waveform generation.
    Note For more information on arbitrary waveform trigger modes, see Advanced Waveform Sequencing and Triggering on Arbitrary Waveform Generators in the Related Information section.
  • Trigger Type—Sets the trigger type to one of the following values:
  • Immediate—Triggers waveform generation as soon as you run the waveform generator.
  • Software—Triggers waveform generation according to settings in an external application.
  • Digital edge—Triggers waveform generation on the rising edge of a specified source terminal. The source terminal must export a signal to use digital edge triggering.

    • Hardware Event Output Terminals

    The settings in the Hardware event output terminals section of the Channel Settings window determine the chassis terminal to which InstrumentStudio exports hardware events.

    Waveform Generator Status

    You can see the current generation status of non-idle channels in the Channel Settings window or through the generation status icon. The generation status icon is next to the Waveform dropdown menu of a channel.

    Table 5. Generation Status of the Waveform Generator
    Icon Status Description

    An icon of a green play button with three green dots underneath.

    		 Generating output Waveform generation is running on this channel.

    An icon of a red rectangle.

    		 Not generating output Waveform generation is stopped on this channel.

    An icon with six green circles arranged in a hexagonal shape.

    		 Waiting for trigger The channel is waiting to start an operation until the trigger condition occurs.

    An icon of a grey circle with three dots underneath.

    		 Unknown status The output status of the channel is unknown. Run the panel to refresh the output status.
    Note Waveform generation stops when you close the waveform generator panel.