niScope Read (poly)

NI High-Speed Digitizers Help (NI-SCOPE)

Edition Date: January 2017

Part Number: 370592AB-01

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NI-SCOPE (English | Japanese)

Initiates an acquisition, waits for it to complete, and acquires data.

Related topics:

Use the pull-down menu to select an instance of this VI.

Cluster

Initiates an acquisition, waits for it to complete, and retrieves the data for a single channel and record.

niScope Read Cluster

/images/reference/en-XX/help/370592AB-01/cio.gif

instrument handle identifies a particular instrument session.

/images/reference/en-XX/help/370592AB-01/cstr.gif

channels specifies the channel from which to acquire data.

For more information, refer to Channel String Syntax.

/images/reference/en-XX/help/370592AB-01/ci32.gif

numSamples is the maximum number of samples to fetch for each waveform; if the acquisition finishes with fewer points than requested, some devices return partial data if the acquisition finished, was aborted, or a timeout of 0 was used. Use –1 for this parameter if you want to fetch all available samples. The VI reads the actual record length and attempts to acquire all available samples. If it fails to complete within the timeout period, the VI returns an error.

/images/reference/en-XX/help/370592AB-01/cdbl.gif

timeout is the time (in seconds) to wait for the data to be acquired. Use 0 for this parameter to tell NI-SCOPE to fetch whatever is currently available. Using -1 for this parameter implies infinite timeout.

/images/reference/en-XX/help/370592AB-01/cerrcodeclst.gif

error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

/images/reference/en-XX/help/370592AB-01/iio.gif

instrument handle out has the same value as the instrument handle.

/images/reference/en-XX/help/370592AB-01/inclst.gif

wfm info contains all the timing and scaling information about the waveform.

/images/reference/en-XX/help/370592AB-01/ii32.gif

actualSamples is the actual number of samples in the acquired waveform; this number may be less than numSamples if the number you request is not available.

/images/reference/en-XX/help/370592AB-01/idbl.gif

absoluteInitialX is the timestamp in seconds of the first fetched sample. This timestamp is comparable between records and acquisitions; devices that do not support this parameter use 0 for this output.

/images/reference/en-XX/help/370592AB-01/idbl.gif

relativeInitialX is the time in seconds from the trigger to the first sample in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

xIncrement indicates the time in seconds between two samples in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

offset is the offset factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

gain is the gain factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved1 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved2 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/icclst.gif

waveform is a cluster containing the initial x value, xIincrement, and a waveform array. This output can be wired directly to the LabVIEW waveform graph, so the waveform is plotted with timing information. The initial x value in the cluster is relative to the trigger. The relative initial x value is the time from the trigger to the first point so the trigger always occurs at time equals zero.

/images/reference/en-XX/help/370592AB-01/idbl.gif

relativeInitialX is the time in seconds from the trigger to the first sample in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

xIncrement indicates the time in seconds between two samples in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/i1ddbl.gif

wfm is an array of waveform data containing one waveform without any timing information.

/images/reference/en-XX/help/370592AB-01/ierrcodeclst.gif

error out contains error information. This output provides standard error out functionality.

WDT

Returns the waveform the digitizer acquires for the specified channel. The VI initiates an acquisition that returns a scaled voltage waveform in a waveform data type that includes timing information.

niScope Read WDT

/images/reference/en-XX/help/370592AB-01/cio.gif

instrument handle identifies a particular instrument session.

/images/reference/en-XX/help/370592AB-01/cstr.gif

channels specifies the channel from which to acquire data.

For more information, refer to Channel String Syntax.

/images/reference/en-XX/help/370592AB-01/ci32.gif

numSamples is the maximum number of samples to fetch for each waveform; if the acquisition finishes with fewer points than requested, some devices return partial data if the acquisition finished, was aborted, or a timeout of 0 was used. Use –1 for this parameter if you want to fetch all available samples. The VI reads the actual record length and attempts to acquire all available samples. If it fails to complete within the timeout period, the VI returns an error.

/images/reference/en-XX/help/370592AB-01/cdbl.gif

timeout is the time (in seconds) to wait for the data to be acquired. Use 0 for this parameter to tell NI-SCOPE to fetch whatever is currently available. Using -1 for this parameter implies infinite timeout.

/images/reference/en-XX/help/370592AB-01/ci32.gif

timestamp Type specifies the time basis for the timestamp on the WDT data.

Defined Values

absolute

relative

/images/reference/en-XX/help/370592AB-01/cerrcodeclst.gif

error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

/images/reference/en-XX/help/370592AB-01/iio.gif

instrument handle out has the same value as the instrument handle.

/images/reference/en-XX/help/370592AB-01/inclst.gif

wfm info contains all the timing and scaling information about the waveform.

/images/reference/en-XX/help/370592AB-01/ii32.gif

actualSamples is the actual number of samples in the acquired waveform; this number may be less than numSamples if the number you request is not available.

/images/reference/en-XX/help/370592AB-01/idbl.gif

absoluteInitialX is the timestamp in seconds of the first fetched sample. This timestamp is comparable between records and acquisitions; devices that do not support this parameter use 0 for this output.

/images/reference/en-XX/help/370592AB-01/idbl.gif

relativeInitialX is the time in seconds from the trigger to the first sample in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

xIncrement indicates the time in seconds between two samples in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

offset is the offset factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

gain is the gain factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved1 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved2 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/iwfm.gif

wfm returns data for wiring to a graph, including the timing information.

/images/reference/en-XX/help/370592AB-01/ierrcodeclst.gif

error out contains error information. This output provides standard error out functionality.

1D Cluster

Initiates an acquisition, waits for it to complete, and retrieves the data for multiple channels and records.

niScope Multi Read Cluster

/images/reference/en-XX/help/370592AB-01/cio.gif

instrument handle identifies a particular instrument session.

/images/reference/en-XX/help/370592AB-01/cstr.gif

channels specifies the channel from which to acquire data.

For more information, refer to Channel String Syntax.

/images/reference/en-XX/help/370592AB-01/ci32.gif

numSamples is the maximum number of samples to fetch for each waveform; if the acquisition finishes with fewer points than requested, some devices return partial data if the acquisition finished, was aborted, or a timeout of 0 was used. Use –1 for this parameter if you want to fetch all available samples. The VI reads the actual record length and attempts to acquire all available samples. If it fails to complete within the timeout period, the VI returns an error.

/images/reference/en-XX/help/370592AB-01/cdbl.gif

timeout is the time (in seconds) to wait for the data to be acquired. Use 0 for this parameter to tell NI-SCOPE to fetch whatever is currently available. Using -1 for this parameter implies infinite timeout.

/images/reference/en-XX/help/370592AB-01/cerrcodeclst.gif

error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

/images/reference/en-XX/help/370592AB-01/iio.gif

instrument handle out has the same value as the instrument handle.

/images/reference/en-XX/help/370592AB-01/i1dnclst.gif

wfm info contains all the timing and scaling information about the waveform.

/images/reference/en-XX/help/370592AB-01/ii32.gif

actualSamples is the actual number of samples in the acquired waveform; this number may be less than numSamples if the number you request is not available.

/images/reference/en-XX/help/370592AB-01/idbl.gif

absoluteInitialX is the timestamp in seconds of the first fetched sample. This timestamp is comparable between records and acquisitions; devices that do not support this parameter use 0 for this output.

/images/reference/en-XX/help/370592AB-01/idbl.gif

relativeInitialX is the time in seconds from the trigger to the first sample in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

xIncrement indicates the time in seconds between two samples in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

offset is the offset factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

gain is the gain factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved1 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved2 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/i1dcclst.gif

waveform is an array of clusters, each containing the initial x value, x increment, and a waveform array. This output can be wired directly to the LabVIEW waveform graph, so each waveform in the array is plotted with timing information. The initial x value in the cluster is the value relative to the trigger. The relative initial x value is the time from the trigger to the first point so the trigger always occurs at time equals zero.

The array of clusters includes waveforms from multiple channels, records, and acquisition types. For example, if the acquisition type is normal there is one waveform per channel per record. If you call the fetch VI during a normal acquisition with the channel string "0,1" the order of the output is:

record 0, channel 0

record 0, channel 1

record 1, channel 0

record 1, channel 1

/images/reference/en-XX/help/370592AB-01/idbl.gif

relativeInitialX is the time in seconds from the trigger to the first sample in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

xIncrement indicates the time in seconds between two samples in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/i1ddbl.gif

wfm is an array of waveform data containing one waveform without any timing information.

/images/reference/en-XX/help/370592AB-01/ierrcodeclst.gif

error out contains error information. This output provides standard error out functionality.

1D WDT

Initiates an acquisition and returns a one-dimensional array of LabVIEW waveform data types that includes timing information. This VI is only supported in LabVIEW 7.0 or later.

niScope Multi Read WDT

/images/reference/en-XX/help/370592AB-01/cio.gif

instrument handle identifies a particular instrument session.

/images/reference/en-XX/help/370592AB-01/cstr.gif

channels specifies the channel from which to acquire data.

For more information, refer to Channel String Syntax.

/images/reference/en-XX/help/370592AB-01/ci32.gif

numSamples is the maximum number of samples to fetch for each waveform; if the acquisition finishes with fewer points than requested, some devices return partial data if the acquisition finished, was aborted, or a timeout of 0 was used. Use –1 for this parameter if you want to fetch all available samples. The VI reads the actual record length and attempts to acquire all available samples. If it fails to complete within the timeout period, the VI returns an error.

/images/reference/en-XX/help/370592AB-01/cdbl.gif

timeout is the time (in seconds) to wait for the data to be acquired. Use 0 for this parameter to tell NI-SCOPE to fetch whatever is currently available. Using -1 for this parameter implies infinite timeout.

/images/reference/en-XX/help/370592AB-01/ci32.gif

timestamp Type specifies the time basis for the timestamp on the WDT data.

Defined Values

absolute

relative

/images/reference/en-XX/help/370592AB-01/cerrcodeclst.gif

error in describes error conditions that occur before this node runs. This input provides standard error in functionality.

/images/reference/en-XX/help/370592AB-01/iio.gif

instrument handle out has the same value as the instrument handle.

/images/reference/en-XX/help/370592AB-01/i1dnclst.gif

wfm info contains all the timing and scaling information about the waveform.

/images/reference/en-XX/help/370592AB-01/ii32.gif

actualSamples is the actual number of samples in the acquired waveform; this number may be less than numSamples if the number you request is not available.

/images/reference/en-XX/help/370592AB-01/idbl.gif

absoluteInitialX is the timestamp in seconds of the first fetched sample. This timestamp is comparable between records and acquisitions; devices that do not support this parameter use 0 for this output.

/images/reference/en-XX/help/370592AB-01/idbl.gif

relativeInitialX is the time in seconds from the trigger to the first sample in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

xIncrement indicates the time in seconds between two samples in the acquired waveform.

/images/reference/en-XX/help/370592AB-01/idbl.gif

offset is the offset factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

gain is the gain factor of the given channel.

Use for scaling binary data with the following formula:

voltage = binary data × gain factor + offset

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved1 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/idbl.gif

reserved2 is reserved. Do not use.

/images/reference/en-XX/help/370592AB-01/i1dwfm.gif

wfm returns a one-dimensional array of LabVIEW waveform data types that contain timing information. If you specify a channel list, NI-SCOPE returns the waveforms in the list order. NI-SCOPE returns these records sequentially, so all record 0 waveforms are first.

For example, with a two-channel list, you would have the following index values:

index 0 = record 0, channel 0

index 1 = record 0, channel 1

index 2 = record 1, channel 0

index 3 = record 1, channel 1

/images/reference/en-XX/help/370592AB-01/ierrcodeclst.gif

error out contains error information. This output provides standard error out functionality.

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