nifgen.Session methods

nifgen.Session.abort()

Aborts any previously initiated signal generation. Call the nifgen_InitiateGeneration method to cause the signal generator to produce a signal again.

nifgen.Session.allocate_named_waveform(waveform_name, waveform_size)

Specifies the size of a named waveform up front so that it can be allocated in onboard memory before loading the associated data. Data can then be loaded in smaller blocks with the niFgen Write (Binary16) Waveform methods.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].allocate_named_waveform(waveform_name, waveform_size)
Parameters:
  • waveform_name (str) – Specifies the name to associate with the allocated waveform.
  • waveform_size (int) –

    Specifies the size of the waveform to allocate in samples.

    Default Value: “4096”
nifgen.Session.allocate_waveform(waveform_size)

Specifies the size of a waveform so that it can be allocated in onboard memory before loading the associated data. Data can then be loaded in smaller blocks with the Write Binary 16 Waveform methods.

Note

The signal generator must not be in the Generating state when you call this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].allocate_waveform(waveform_size)
Parameters:waveform_size (int) – Specifies, in samples, the size of the waveform to allocate.
Return type:int
Returns:The handle that identifies the new waveform. This handle is used later when referring to this waveform.
nifgen.Session.clear_arb_memory()

Removes all previously created arbitrary waveforms, sequences, and scripts from the signal generator memory and invalidates all waveform handles, sequence handles, and waveform names.

Note

The signal generator must not be in the Generating state when you call this method.

nifgen.Session.clear_arb_sequence(sequence_handle)

Removes a previously created arbitrary sequence from the signal generator memory and invalidates the sequence handle.

Note

The signal generator must not be in the Generating state when you call this method.

Parameters:sequence_handle (int) –

Specifies the handle of the arbitrary sequence that you want the signal generator to remove. You can create an arbitrary sequence using the nifgen_CreateArbSequence or nifgen_CreateAdvancedArbSequence method. These methods return a handle that you use to identify the sequence.

Defined Value:
NIFGEN_VAL_ALL_SEQUENCES—Remove all sequences from the signal generator

Default Value: None

Note

One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.
nifgen.Session.clear_arb_waveform(waveform_handle)

Removes a previously created arbitrary waveform from the signal generator memory and invalidates the waveform handle.

Note

The signal generator must not be in the Generating state when you call this method.

Parameters:waveform_handle (int) –

Specifies the handle of the arbitrary waveform that you want the signal generator to remove.

You can create multiple arbitrary waveforms using one of the following niFgen Create Waveform methods:

Defined Value:

NIFGEN_VAL_ALL_WAVEFORMS—Remove all waveforms from the signal generator.

Default Value: None

Note

One or more of the referenced methods are not in the Python API for this driver.

Note

One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.
nifgen.Session.clear_freq_list(frequency_list_handle)

Removes a previously created frequency list from the signal generator memory and invalidates the frequency list handle.

Note

The signal generator must not be in the Generating state when you call this method.

Parameters:frequency_list_handle (int) –

Specifies the handle of the frequency list you want the signal generator to remove. You create multiple frequency lists using nifgen.Session.create_freq_list(). nifgen.Session.create_freq_list() returns a handle that you use to identify each list. Specify a value of -1 to clear all frequency lists.

Defined Value

NIFGEN_VAL_ALL_FLISTS—Remove all frequency lists from the signal generator.

Default Value: None

Note

One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.
nifgen.Session.clear_user_standard_waveform()

Clears the user-defined waveform created by the nifgen_DefineUserStandardWaveform method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].clear_user_standard_waveform()
nifgen.Session.commit()

Causes a transition to the Committed state. This method verifies property values, reserves the device, and commits the property values to the device. If the property values are all valid, NI-FGEN sets the device hardware configuration to match the session configuration. This method does not support the NI 5401/5404/5411/5431 signal generators.

In the Committed state, you can load waveforms, scripts, and sequences into memory. If any properties are changed, NI-FGEN implicitly transitions back to the Idle state, where you can program all session properties before applying them to the device. This method has no effect if the device is already in the Committed or Generating state and returns a successful status value.

Calling this VI before the niFgen Initiate Generation VI is optional but has the following benefits:

  • Routes are committed, so signals are exported or imported.
  • Any Reference Clock and external clock circuits are phase-locked.
  • A subsequent nifgen.Session._initiate_generation() method can run faster because the device is already configured.
nifgen.Session.configure_arb_sequence(sequence_handle, gain, offset)

Configures the signal generator properties that affect arbitrary sequence generation. Sets the nifgen.Session.arb_sequence_handle, nifgen.Session.arb_gain, and nifgen.Session.arb_offset properties.

Note

The signal generator must not be in the Generating state when you call this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].configure_arb_sequence(sequence_handle, gain, offset)
Parameters:
  • sequence_handle (int) –

    Specifies the handle of the arbitrary sequence that you want the signal generator to produce. NI-FGEN sets the nifgen.Session.arb_sequence_handle property to this value. You can create an arbitrary sequence using the nifgen.Session.create_arb_sequence() or nifgen.Session.create_advanced_arb_sequence() method. These methods return a handle that you use to identify the sequence.

    Default Value: None

  • gain (float) –

    Specifies the factor by which the signal generator scales the arbitrary waveforms in the sequence. When you create an arbitrary waveform, you must first normalize the data points to a range of –1.00 to +1.00. You can use this parameter to scale the waveform to other ranges. The gain is applied before the offset is added.

    For example, to configure the output signal to range from –2.00 to +2.00 V, set gain to 2.00.

    Units: unitless

    Default Value: None

  • offset (float) –

    Specifies the value the signal generator adds to the arbitrary waveform data. When you create arbitrary waveforms, you must first normalize the data points to a range of –1.00 to +1.00 V. You can use this parameter to shift the range of the arbitrary waveform. NI-FGEN sets the nifgen.Session.arb_offset property to this value.

    For example, to configure the output signal to range from 0.00 to 2.00 V instead of –1.00 to 1.00 V, set the offset to 1.00.

    Units: volts

    Default Value: None
nifgen.Session.configure_arb_waveform(waveform_handle, gain, offset)

Configures the properties of the signal generator that affect arbitrary waveform generation. Sets the nifgen.Session.arb_waveform_handle, nifgen.Session.arb_gain, and nifgen.Session.arb_offset properties.

Note

The signal generator must not be in the Generating state when you call this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].configure_arb_waveform(waveform_handle, gain, offset)
Parameters:
  • waveform_handle (int) –

    Specifies the handle of the arbitrary waveform you want the signal generator to produce. NI-FGEN sets the nifgen.Session.arb_waveform_handle property to this value. You can create an arbitrary waveform using one of the following niFgen Create Waveform methods:

    These methods return a handle that you use to identify the waveform.

    Default Value: None

    Note

    One or more of the referenced methods are not in the Python API for this driver.

  • gain (float) –

    Specifies the factor by which the signal generator scales the arbitrary waveforms in the sequence. When you create an arbitrary waveform, you must first normalize the data points to a range of –1.00 to +1.00. You can use this parameter to scale the waveform to other ranges. The gain is applied before the offset is added.

    For example, to configure the output signal to range from –2.00 to +2.00 V, set gain to 2.00.

    Units: unitless

    Default Value: None

  • offset (float) –

    Specifies the value the signal generator adds to the arbitrary waveform data. When you create arbitrary waveforms, you must first normalize the data points to a range of –1.00 to +1.00 V. You can use this parameter to shift the range of the arbitrary waveform. NI-FGEN sets the nifgen.Session.arb_offset property to this value.

    For example, to configure the output signal to range from 0.00 to 2.00 V instead of –1.00 to 1.00 V, set the offset to 1.00.

    Units: volts

    Default Value: None
nifgen.Session.configure_custom_fir_filter_coefficients(coefficients_array)

Sets the FIR filter coefficients used by the onboard signal processing block. The values are coerced to the closest settings achievable by the signal generator.

Refer to the FIR Filter topic for your device in the NI Signal Generators Help for more information about FIR filter coefficients. This method is supported only for the NI 5441.

Note

The signal generator must not be in the Generating state when you call this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].configure_custom_fir_filter_coefficients(coefficients_array)
Parameters:coefficients_array (list of float) – Specifies the array of data the onboard signal processor uses for the FIR filter coefficients. For the NI 5441, provide a symmetric array of 95 coefficients to this parameter. The array must have at least as many elements as the value that you specify in the numberOfCoefficients parameter in this method. The coefficients should range between –1.00 and +1.00.
nifgen.Session.configure_digital_edge_script_trigger(trigger_id, source, edge=nifgen.ScriptTriggerDigitalEdgeEdge.RISING)

Configures the specified Script Trigger for digital edge triggering.

Parameters:
  • trigger_id (str) –

    Specifies the Script Trigger used for triggering.

    Defined Values

    Default Value: “ScriptTrigger0”

    ”ScriptTrigger0” Script Trigger 0
    ”ScriptTrigger1” Script Trigger 1
    ”ScriptTrigger2” Script Trigger 2
    ”ScriptTrigger3” Script Trigger 3
  • source (str) –

    Specifies which trigger source the signal generator uses.

    Defined Values

    Default Value: “PFI0”

    ”PFI0” PFI 0
    ”PFI1” PFI 1
    ”PFI2” PFI 2
    ”PFI3” PFI 3
    ”PFI4” PFI 4
    ”PFI5” PFI 5
    ”PFI6” PFI 6
    ”PFI7” PFI 7
    ”PXI_Trig0” PXI trigger line 0 or RTSI line 0
    ”PXI_Trig1” PXI trigger line 1 or RTSI line 1
    ”PXI_Trig2” PXI trigger line 2 or RTSI line 2
    ”PXI_Trig3” PXI trigger line 3 or RTSI line 3
    ”PXI_Trig4” PXI trigger line 4 or RTSI line 4
    ”PXI_Trig5” PXI trigger line 5 or RTSI line 5
    ”PXI_Trig6” PXI trigger line 6 or RTSI line 6
    ”PXI_Trig7” PXI trigger line 7 or RTSI line 7
    ”PXI_Star” PXI star trigger line
  • edge (nifgen.ScriptTriggerDigitalEdgeEdge) –

    Specifies the edge to detect.

    **Defined Values**

    **Default Value:** RISING

    RISING Occurs when the signal transitions from low level to high level.
    FALLING Occurs when the signal transitions from high level to low level.

    Note

    One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.
nifgen.Session.configure_digital_edge_start_trigger(source, edge=nifgen.StartTriggerDigitalEdgeEdge.RISING)

Configures the Start Trigger for digital edge triggering.

Parameters:
  • source (str) –

    Specifies which trigger source the signal generator uses.

    Defined Values

    Default Value: “PFI0”

    ”PFI0” PFI 0
    ”PFI1” PFI 1
    ”PFI2” PFI 2
    ”PFI3” PFI 3
    ”PFI4” PFI 4
    ”PFI5” PFI 5
    ”PFI6” PFI 6
    ”PFI7” PFI 7
    ”PXI_Trig0” PXI trigger line 0 or RTSI line 0
    ”PXI_Trig1” PXI trigger line 1 or RTSI line 1
    ”PXI_Trig2” PXI trigger line 2 or RTSI line 2
    ”PXI_Trig3” PXI trigger line 3 or RTSI line 3
    ”PXI_Trig4” PXI trigger line 4 or RTSI line 4
    ”PXI_Trig5” PXI trigger line 5 or RTSI line 5
    ”PXI_Trig6” PXI trigger line 6 or RTSI line 6
    ”PXI_Trig7” PXI trigger line 7 or RTSI line 7
    ”PXI_Star” PXI star trigger line
  • edge (nifgen.StartTriggerDigitalEdgeEdge) –

    Specifies the edge to detect.

    **Defined Values**

    **Default Value:** RISING

    RISING Occurs when the signal transitions from low level to high level.
    FALLING Occurs when the signal transitions from high level to low level.

    Note

    One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.
nifgen.Session.configure_digital_level_script_trigger(trigger_id, source, trigger_when)

Configures the specified Script Trigger for digital level triggering.

Parameters:
  • trigger_id (str) –

    Specifies the Script Trigger used for triggering.

    Defined Values

    Default Value: “ScriptTrigger0”

    ”ScriptTrigger0” Script Trigger 0
    ”ScriptTrigger1” Script Trigger 1
    ”ScriptTrigger2” Script Trigger 2
    ”ScriptTrigger3” Script Trigger 3
  • source (str) –

    Specifies which trigger source the signal generator uses.

    Defined Values

    Default Value: “PFI0”

    ”PFI0” PFI 0
    ”PFI1” PFI 1
    ”PFI2” PFI 2
    ”PFI3” PFI 3
    ”PFI4” PFI 4
    ”PFI5” PFI 5
    ”PFI6” PFI 6
    ”PFI7” PFI 7
    ”PXI_Trig0” PXI trigger line 0 or RTSI line 0
    ”PXI_Trig1” PXI trigger line 1 or RTSI line 1
    ”PXI_Trig2” PXI trigger line 2 or RTSI line 2
    ”PXI_Trig3” PXI trigger line 3 or RTSI line 3
    ”PXI_Trig4” PXI trigger line 4 or RTSI line 4
    ”PXI_Trig5” PXI trigger line 5 or RTSI line 5
    ”PXI_Trig6” PXI trigger line 6 or RTSI line 6
    ”PXI_Trig7” PXI trigger line 7 or RTSI line 7
    ”PXI_Star” PXI star trigger line
  • trigger_when (nifgen.TriggerWhen) –

    Specifies whether the Script Trigger asserts on a high or low digital level.

    Defined Values

    Default Value: “HighLevel”

    ”HighLevel” Script Trigger asserts on a high digital level.
    ”LowLevel” Script Trigger asserts on a low digital level.
nifgen.Session.configure_freq_list(frequency_list_handle, amplitude, dc_offset=0.0, start_phase=0.0)

Configures the properties of the signal generator that affect frequency list generation (the nifgen.Session.freq_list_handle, nifgen.Session.func_amplitude, nifgen.Session.func_dc_offset, and nifgen.Session.func_start_phase properties).

Note

The signal generator must not be in the Generating state when you call this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].configure_freq_list(frequency_list_handle, amplitude, dc_offset=0.0, start_phase=0.0)
Parameters:
  • frequency_list_handle (int) – Specifies the handle of the frequency list that you want the signal generator to produce. NI-FGEN sets the nifgen.Session.freq_list_handle property to this value. You can create a frequency list using the nifgen.Session.create_freq_list() method, which returns a handle that you use to identify the list. Default Value: None
  • amplitude (float) –

    Specifies the amplitude of the standard waveform that you want the signal generator to produce. This value is the amplitude at the output terminal. NI-FGEN sets the nifgen.Session.func_amplitude property to this value.

    For example, to produce a waveform ranging from –5.00 V to +5.00 V, set the amplitude to 10.00 V.

    Units: peak-to-peak voltage

    Default Value: None

    Note

    This parameter does not affect signal generator behavior when you set the waveform parameter of the nifgen.Session.configure_standard_waveform() method to DC.

  • dc_offset (float) –

    Specifies the DC offset of the standard waveform that you want the signal generator to produce. The value is the offset from ground to the center of the waveform you specify with the waveform parameter, observed at the output terminal. For example, to configure a waveform with an amplitude of 10.00 V to range from 0.00 V to +10.00 V, set the dcOffset to 5.00 V. NI-FGEN sets the nifgen.Session.func_dc_offset property to this value.

    Units: volts

    Default Value: None

  • start_phase (float) –

    Specifies the horizontal offset of the standard waveform you want the signal generator to produce. Specify this property in degrees of one waveform cycle. NI-FGEN sets the nifgen.Session.func_start_phase property to this value. A start phase of 180 degrees means output generation begins halfway through the waveform. A start phase of 360 degrees offsets the output by an entire waveform cycle, which is identical to a start phase of 0 degrees.

    Units: degrees of one cycle

    Default Value: None degrees

    Note

    This parameter does not affect signal generator behavior when you set the waveform parameter to DC.
nifgen.Session.configure_standard_waveform(waveform, amplitude, frequency, dc_offset=0.0, start_phase=0.0)

Configures the following properties of the signal generator that affect standard waveform generation:

Note

You must call the nifgen.Session.ConfigureOutputMode() method with the outputMode parameter set to FUNC before calling this method.

Note

One or more of the referenced methods are not in the Python API for this driver.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].configure_standard_waveform(waveform, amplitude, frequency, dc_offset=0.0, start_phase=0.0)
Parameters:
  • waveform (nifgen.Waveform) –

    Specifies the standard waveform that you want the signal generator to produce. NI-FGEN sets the nifgen.Session.func_waveform property to this value.

    **Defined Values**

    Default Value: SINE

    SINE Specifies that the signal generator produces a sinusoid waveform.
    SQUARE Specifies that the signal generator produces a square waveform.
    TRIANGLE Specifies that the signal generator produces a triangle waveform.
    RAMP_UP Specifies that the signal generator produces a positive ramp waveform.
    RAMP_DOWN Specifies that the signal generator produces a negative ramp waveform.
    DC Specifies that the signal generator produces a constant voltage.
    NOISE Specifies that the signal generator produces white noise.
    USER Specifies that the signal generator produces a user-defined waveform as defined with the nifgen_DefineUserStandardWaveform method.
  • amplitude (float) –

    Specifies the amplitude of the standard waveform that you want the signal generator to produce. This value is the amplitude at the output terminal. NI-FGEN sets the nifgen.Session.func_amplitude property to this value.

    For example, to produce a waveform ranging from –5.00 V to +5.00 V, set the amplitude to 10.00 V.

    Units: peak-to-peak voltage

    Default Value: None

    Note

    This parameter does not affect signal generator behavior when you set the waveform parameter of the nifgen.Session.configure_standard_waveform() method to DC.

  • frequency (float) –
    Specifies the frequency of the standard waveform that you want the signal generator to produce. NI-FGEN sets the nifgen.Session.func_frequency property to this value.

    Units: hertz

    Default Value: None

    Note

    This parameter does not affect signal generator behavior when you set the waveform parameter of the nifgen.Session.configure_standard_waveform() method to DC.

  • dc_offset (float) –

    Specifies the DC offset of the standard waveform that you want the signal generator to produce. The value is the offset from ground to the center of the waveform you specify with the waveform parameter, observed at the output terminal. For example, to configure a waveform with an amplitude of 10.00 V to range from 0.00 V to +10.00 V, set the dcOffset to 5.00 V. NI-FGEN sets the nifgen.Session.func_dc_offset property to this value.

    Units: volts

    Default Value: None

  • start_phase (float) –

    Specifies the horizontal offset of the standard waveform that you want the signal generator to produce. Specify this parameter in degrees of one waveform cycle. NI-FGEN sets the nifgen.Session.func_start_phase property to this value. A start phase of 180 degrees means output generation begins halfway through the waveform. A start phase of 360 degrees offsets the output by an entire waveform cycle, which is identical to a start phase of 0 degrees.

    Units: degrees of one cycle

    Default Value: 0.00

    Note

    This parameter does not affect signal generator behavior when you set the waveform parameter to DC.
nifgen.Session.create_advanced_arb_sequence(waveform_handles_array, loop_counts_array, sample_counts_array=None, marker_location_array=None)

Creates an arbitrary sequence from an array of waveform handles and an array of corresponding loop counts. This method returns a handle that identifies the sequence. You pass this handle to the nifgen.Session.configure_arb_sequence() method to specify what arbitrary sequence you want the signal generator to produce.

The nifgen.Session.create_advanced_arb_sequence() method extends on the nifgen.Session.create_arb_sequence() method by adding the ability to set the number of samples in each sequence step and to set marker locations.

An arbitrary sequence consists of multiple waveforms. For each waveform, you specify the number of times the signal generator produces the waveform before proceeding to the next waveform. The number of times to repeat a specific waveform is called the loop count.

Note

The signal generator must not be in the Generating state when you call this method. You must call the nifgen_ConfigureOutputMode method to set the outputMode parameter to SEQ before calling this method.

Parameters:
  • waveform_handles_array (list of int) –

    Specifies the array of waveform handles from which you want to create a new arbitrary sequence. The array must have at least as many elements as the value that you specify in sequenceLength. Each waveformHandlesArray element has a corresponding loopCountsArray element that indicates how many times that waveform is repeated. You obtain waveform handles when you create arbitrary waveforms with the nifgen_AllocateWaveform method or one of the following niFgen CreateWaveform methods:

    • nifgen_CreateWaveformF64
    • nifgen_CreateWaveformI16
    • nifgen_CreateWaveformFromFileI16
    • nifgen_CreateWaveformFromFileF64
    • nifgen_CreateWaveformFromFileHWS

    Default Value: None

  • loop_counts_array (list of int) –

    Specifies the array of loop counts you want to use to create a new arbitrary sequence. The array must have at least as many elements as the value that you specify in the sequenceLength parameter. Each loopCountsArray element corresponds to a waveformHandlesArray element and indicates how many times to repeat that waveform. Each element of the loopCountsArray must be less than or equal to the maximum number of loop counts that the signal generator allows. You can obtain the maximum loop count from maximumLoopCount in the nifgen_QueryArbSeqCapabilities method.

    Default Value: None

  • sample_counts_array (list of int) –

    Specifies the array of sample counts that you want to use to create a new arbitrary sequence. The array must have at least as many elements as the value you specify in the sequenceLength parameter. Each sampleCountsArray element corresponds to a waveformHandlesArray element and indicates the subset, in samples, of the given waveform to generate. Each element of the sampleCountsArray must be larger than the minimum waveform size, a multiple of the waveform quantum and no larger than the number of samples in the corresponding waveform. You can obtain these values by calling the nifgen_QueryArbWfmCapabilities method.

    Default Value: None

  • marker_location_array (list of int) –

    Specifies the array of marker locations to where you want a marker to be generated in the sequence. The array must have at least as many elements as the value you specify in the sequenceLength parameter. Each markerLocationArray element corresponds to a waveformHandlesArray element and indicates where in the waveform a marker is to generate. The marker location must be less than the size of the waveform the marker is in. The markers are coerced to the nearest marker quantum and the coerced values are returned in the coercedMarkersArray parameter.

    If you do not want a marker generated for a particular sequence stage, set this parameter to NIFGEN_VAL_NO_MARKER.

    Defined Value: NIFGEN_VAL_NO_MARKER

    Default Value: None

    Note

    One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.
Return type:

tuple (coerced_markers_array, sequence_handle)

WHERE

coerced_markers_array (list of int):

Returns an array of all given markers that are coerced (rounded) to the nearest marker quantum. Not all devices coerce markers.

Default Value: None

sequence_handle (int):

Returns the handle that identifies the new arbitrary sequence. You can pass this handle to nifgen_ConfigureArbSequence to generate the arbitrary sequence.
nifgen.Session.create_arb_sequence(waveform_handles_array, loop_counts_array)

Creates an arbitrary sequence from an array of waveform handles and an array of corresponding loop counts. This method returns a handle that identifies the sequence. You pass this handle to the nifgen_ConfigureArbSequence method to specify what arbitrary sequence you want the signal generator to produce.

An arbitrary sequence consists of multiple waveforms. For each waveform, you can specify the number of times that the signal generator produces the waveform before proceeding to the next waveform. The number of times to repeat a specific waveform is called the loop count.

Note

You must call the nifgen_ConfigureOutputMode method to set the outputMode parameter to SEQ before calling this method.

Parameters:
  • waveform_handles_array (list of int) –

    Specifies the array of waveform handles from which you want to create a new arbitrary sequence. The array must have at least as many elements as the value that you specify in sequenceLength. Each waveformHandlesArray element has a corresponding loopCountsArray element that indicates how many times that waveform is repeated. You obtain waveform handles when you create arbitrary waveforms with the nifgen_AllocateWaveform method or one of the following niFgen CreateWaveform methods:

    • nifgen_CreateWaveformF64
    • nifgen_CreateWaveformI16
    • nifgen_CreateWaveformFromFileI16
    • nifgen_CreateWaveformFromFileF64
    • nifgen_CreateWaveformFromFileHWS

    Default Value: None

  • loop_counts_array (list of int) –

    Specifies the array of loop counts you want to use to create a new arbitrary sequence. The array must have at least as many elements as the value that you specify in the sequenceLength parameter. Each loopCountsArray element corresponds to a waveformHandlesArray element and indicates how many times to repeat that waveform. Each element of the loopCountsArray must be less than or equal to the maximum number of loop counts that the signal generator allows. You can obtain the maximum loop count from maximumLoopCount in the nifgen_QueryArbSeqCapabilities method.

    Default Value: None
Return type:

int
Returns:

Returns the handle that identifies the new arbitrary sequence. You can pass this handle to nifgen_ConfigureArbSequence to generate the arbitrary sequence.
nifgen.Session.create_freq_list(waveform, frequency_array, duration_array)

Creates a frequency list from an array of frequencies (frequencyArray) and an array of durations (durationArray). The two arrays should have the same number of elements, and this value must also be the size of the frequencyListLength. The method returns a handle that identifies the frequency list (the frequencyListHandle). You can pass this handle to nifgen_ConfigureFreqList to specify what frequency list you want the signal generator to produce.

A frequency list consists of a list of frequencies and durations. The signal generator generates each frequency for the given amount of time and then proceeds to the next frequency. When the end of the list is reached, the signal generator starts over at the beginning of the list.

Note

The signal generator must not be in the Generating state when you call this method.

Parameters:
  • waveform (nifgen.Waveform) –

    Specifies the standard waveform that you want the signal generator to produce. NI-FGEN sets the nifgen.Session.func_waveform property to this value.

    **Defined Values**

    Default Value: SINE

    SINE Specifies that the signal generator produces a sinusoid waveform.
    SQUARE Specifies that the signal generator produces a square waveform.
    TRIANGLE Specifies that the signal generator produces a triangle waveform.
    RAMP_UP Specifies that the signal generator produces a positive ramp waveform.
    RAMP_DOWN Specifies that the signal generator produces a negative ramp waveform.
    DC Specifies that the signal generator produces a constant voltage.
    NOISE Specifies that the signal generator produces white noise.
    USER Specifies that the signal generator produces a user-defined waveform as defined with the nifgen_DefineUserStandardWaveform method.
  • frequency_array (list of float) –

    Specifies the array of frequencies to form the frequency list. The array must have at least as many elements as the value you specify in frequencyListLength. Each frequencyArray element has a corresponding durationArray element that indicates how long that frequency is repeated.

    Units: hertz

    Default Value: None

  • duration_array (list of float) –

    Specifies the array of durations to form the frequency list. The array must have at least as many elements as the value that you specify in frequencyListLength. Each durationArray element has a corresponding frequencyArray element and indicates how long in seconds to generate the corresponding frequency.

    Units: seconds

    Default Value: None
Return type:

int
Returns:

Returns the handle that identifies the new frequency list. You can pass this handle to nifgen_ConfigureFreqList to generate the arbitrary sequence.
nifgen.Session.create_waveform_from_file_f64(file_name, byte_order)

This method takes the floating point double (F64) data from the specified file and creates an onboard waveform for use in Arbitrary Waveform or Arbitrary Sequence output mode. The waveformHandle returned by this method can later be used for setting the active waveform, changing the data in the waveform, building sequences of waveforms, or deleting the waveform when it is no longer needed.

Note

The F64 data must be between –1.0 and +1.0 V. Use the nifgen.Session.digital_gain property to generate different voltage outputs.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].create_waveform_from_file_f64(file_name, byte_order)
Parameters:
  • file_name (str) – The full path and name of the file where the waveform data resides.
  • byte_order (nifgen.ByteOrder) –

    Specifies the byte order of the data in the file.

    **Defined Values**


    **Default Value:** LITTLE
    LITTLE Little Endian Data—The least significant bit is stored at the lowest address, followed by the other bits, in order of increasing significance.
    BIG Big Endian Data—The most significant bit is stored at the lowest address, followed by the other bits, in order of decreasing significance.

    Note

    Data written by most applications in Windows (including LabWindows™/CVI™) is in Little Endian format. Data written to a file from LabVIEW is in Big Endian format by default on all platforms. Big Endian and Little Endian refer to the way data is stored in memory, which can differ on different processors.
Return type:

int
Returns:

The handle that identifies the new waveform. This handle is used later when referring to this waveform.
nifgen.Session.create_waveform_from_file_i16(file_name, byte_order)

Takes the binary 16-bit signed integer (I16) data from the specified file and creates an onboard waveform for use in Arbitrary Waveform or Arbitrary Sequence output mode. The waveformHandle returned by this method can later be used for setting the active waveform, changing the data in the waveform, building sequences of waveforms, or deleting the waveform when it is no longer needed.

Note

The I16 data (values between –32768 and +32767) is assumed to represent –1 to +1 V. Use the nifgen.Session.digital_gain property to generate different voltage outputs.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].create_waveform_from_file_i16(file_name, byte_order)
Parameters:
  • file_name (str) – The full path and name of the file where the waveform data resides.
  • byte_order (nifgen.ByteOrder) –

    Specifies the byte order of the data in the file.

    **Defined Values**


    **Default Value:** LITTLE
    LITTLE Little Endian Data—The least significant bit is stored at the lowest address, followed by the other bits, in order of increasing significance.
    BIG Big Endian Data—The most significant bit is stored at the lowest address, followed by the other bits, in order of decreasing significance.

    Note

    Data written by most applications in Windows (including LabWindows™/CVI™) is in Little Endian format. Data written to a file from LabVIEW is in Big Endian format by default on all platforms. Big Endian and Little Endian refer to the way data is stored in memory, which can differ on different processors.
Return type:

int
Returns:

The handle that identifies the new waveform. This handle is used later when referring to this waveform.
nifgen.Session.create_waveform_numpy(waveform_data_array)

Creates an onboard waveform for use in Arbitrary Waveform output mode or Arbitrary Sequence output mode.

Note

You must set nifgen.Session.output_mode to ARB or SEQ before calling this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].create_waveform(waveform_data_array)
Parameters:waveform_data_array (list of float) – Array of data for the new arbitrary waveform. This may be an iterable of float, or for best performance a numpy.ndarray of dtype int16 or float64.
Return type:int
Returns:The handle that identifies the new waveform. This handle is used in other methods when referring to this waveform.
nifgen.Session.define_user_standard_waveform(waveform_data_array)

Defines a user waveform for use in either Standard Method or Frequency List output mode.

To select the waveform, set the waveform parameter to USER with either the nifgen_ConfigureStandardWaveform or the nifgen_CreateFreqList method.

The waveform data must be scaled between –1.0 and 1.0. Use the amplitude parameter in the nifgen.Session.configure_standard_waveform() method to generate different output voltages.

Note

You must call the nifgen_ConfigureOutputMode method to set the outputMode parameter to FUNC or FREQ_LIST before calling this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].define_user_standard_waveform(waveform_data_array)
Parameters:waveform_data_array (list of float) –

Specifies the array of data you want to use for the new arbitrary waveform. The array must have at least as many elements as the value that you specify in waveformSize.

You must normalize the data points in the array to be between –1.00 and +1.00.

Default Value: None
nifgen.Session.delete_named_waveform(waveform_name)

Removes a previously created arbitrary waveform from the signal generator memory and invalidates the waveform handle.

Note

The signal generator must not be in the Generating state when you call this method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].delete_named_waveform(waveform_name)
Parameters:waveform_name (str) – Specifies the name to associate with the allocated waveform.
nifgen.Session.delete_script(script_name)

Deletes the specified script from onboard memory.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].delete_script(script_name)
Parameters:script_name (str) – Specifies the name of the script you want to delete. The script name appears in the text of the script following the script keyword.
nifgen.Session.disable()

Places the instrument in a quiescent state where it has minimal or no impact on the system to which it is connected. The analog output and all exported signals are disabled.

nifgen.Session.export_signal(signal, output_terminal, signal_identifier="")

Routes signals (clocks, triggers, and events) to the output terminal you specify.

Any routes created within a session persist after the session closes to prevent signal glitching. To unconfigure signal routes created in previous sessions, set resetDevice in the nifgen.Session.init() method to True or use the nifgen.Session.reset_device() method.

If you export a signal with this method and commit the session, the signal is routed to the output terminal you specify.

Note

One or more of the referenced methods are not in the Python API for this driver.

Parameters:
  • signal (nifgen.Signal) –

    Specifies the source of the signal to route. **Defined Values**

    ONBOARD_REFERENCE_CLOCK Onboard 10 MHz synchronization clock (PCI only)
    SYNC_OUT SYNC OUT signal The SYNC OUT signal is normally generated on the SYNC OUT front panel connector.
    START_TRIGGER Start Trigger
    MARKER_EVENT Marker Event
    SAMPLE_CLOCK_TIMEBASE The clock from which the Sample Clock is derived
    SYNCHRONIZATION Synchronization strobe (NI 5404/5411/5431 only) A synchronization strobe is used to guarantee absolute synchronization between two or more signal generators.
    SAMPLE_CLOCK Sample Clock
    REFERENCE_CLOCK PLL Reference Clock
    SCRIPT_TRIGGER Script Trigger
    READY_FOR_START_EVENT Ready For Start Event
    STARTED_EVENT Started Event
    DONE_EVENT Done Event
    DATA_MARKER_EVENT Data Marker Event

    Note

    One or more of the referenced values are not in the Python API for this driver. Enums that only define values, or represent True/False, have been removed.

  • output_terminal (str) –

    Specifies the output terminal to export the signal. **Defined Values**

    ”” (empty string) Do not export signal
    ”PFI0” PFI line 0
    ”PFI1” PFI line 1
    ”PFI4” PFI line 4
    ”PFI5” PFI line 5
    ”PXI_Trig0” PXI or RTSI line 0
    ”PXI_Trig1” PXI or RTSI line 1
    ”PXI_Trig2” PXI or RTSI line 2
    ”PXI_Trig3” PXI or RTSI line 3
    ”PXI_Trig4” PXI or RTSI line 4
    ”PXI_Trig5” PXI or RTSI line 5
    ”PXI_Trig6” PXI or RTSI line 6
    ”PXI_Trig7” PXI or RTSI line 7
    ”DDC_ClkOut” Clock out from DDC connector
    ”PXI_Star” PXI star trigger line

    Note

    The following Defined Values are examples of possible output terminals. For a complete list of the output terminals available on your device, refer to the Routes topic for your device or the Device Routes tab in MAX.

  • signal_identifier (str) –

    Specifies which instance of the selected signal to export. **Defined Values**

    ”” (empty string) Default (for non instance-based signals)
    ”ScriptTrigger0” Script Trigger 0
    ”ScriptTrigger1” Script Trigger 1
    ”ScriptTrigger2” Script Trigger 2
    ”ScriptTrigger3” Script Trigger 3
    ”Marker0” Marker 0
    ”Marker1” Marker 1
    ”Marker2” Marker 2
    ”Marker3” Marker 3
    ”DataMarker0” Data Marker 0*
    ”DataMarker1” Data Marker 1*
    ”DataMarker2” Data Marker 2*
    ”DataMarker3” Data Marker 3*
    * These Data Marker values apply only to single-channel devices or to multichannel devices that are configured for single-channel operation. When using a device that is configured for multichannel operation, specify the channel number along with the signal identifier. For example, to export Data Marker 0 on channel 1 of a device configured for multichannel operation, use the value “1/ DataMarker0.” If you do not specify a channel when using a device configured for multichannel generation, DataMarker0 generates on all channels.  
nifgen.Session.get_ext_cal_last_date_and_time()

Returns the date and time of the last successful external calibration. The time returned is 24-hour (military) local time; for example, if the device was calibrated at 2:30 PM, this method returns 14 for the hour parameter and 30 for the minute parameter.

Return type:datetime.datetime
Returns:Indicates date and time of the last calibration.
nifgen.Session.get_ext_cal_last_temp()

Returns the temperature at the last successful external calibration. The temperature is returned in degrees Celsius.

Return type:float
Returns:Specifies the temperature at the last successful calibration in degrees Celsius.

Returns the recommended interval between external calibrations in months.

Return type:datetime.timedelta
Returns:Specifies the recommended interval between external calibrations in months.
nifgen.Session.get_fir_filter_coefficients()
Returns the FIR filter coefficients used by the onboard signal processing block. These coefficients are determined by NI-FGEN and based on the FIR filter type and corresponding property (Alpha, Passband, BT) unless you are using the custom filter. If you are using a custom filter, the coefficients returned are those set with the nifgen_ConfigureCustomFIRFilterCoefficients method coerced to the quantized values used by the device.
To use this method, first call an instance of the nifgen.Session.get_fir_filter_coefficients() method with the coefficientsArray parameter set to VI_NULL. Calling the method in this state returns the current size of the coefficientsArray as the value of the numberOfCoefficientsRead parameter. Create an array of this size, and call the nifgen.Session.get_fir_filter_coefficients() method a second time, passing the new array as the coefficientsArray parameter and the size as the arraySize parameter. This second method call populates the array with the FIR filter coefficients.
Refer to the FIR Filter topic for your device in the NI Signal Generators Help for more information about FIR filter coefficients. This method is supported only for the NI 5441.
Default Value: None

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].get_fir_filter_coefficients()
Return type:int
Returns:Specifies the array of data containing the number of coefficients you want to read.
nifgen.Session.get_hardware_state()

Returns the current hardware state of the device and, if the device is in the hardware error state, the current hardware error.

Note

Hardware states do not necessarily correspond to NI-FGEN states.

Return type:nifgen.HardwareState
Returns:Returns the hardware state of the signal generator.

Defined Values

IDLE The device is in the Idle state.
WAITING_FOR_START_TRIGGER The device is waiting for Start Trigger.
RUNNING The device is in the Running state.
DONE The generation has completed successfully.
HARDWARE_ERROR There is a hardware error.
nifgen.Session.get_self_cal_last_date_and_time()

Returns the date and time of the last successful self-calibration.

Return type:datetime.datetime
Returns:Returns the date and time the device was last calibrated.
nifgen.Session.get_self_cal_last_temp()

Returns the temperature at the last successful self-calibration. The temperature is returned in degrees Celsius.

Return type:float
Returns:Specifies the temperature at the last successful calibration in degrees Celsius.
nifgen.Session.get_self_cal_supported()

Returns whether the device supports self–calibration.

Return type:bool
Returns:Returns whether the device supports self-calibration.

**Defined Values**

True Self–calibration is supported.
False Self–calibration is not supported.
nifgen.Session.is_done()

Determines whether the current generation is complete. This method sets the done parameter to True if the session is in the Idle or Committed states.

Note

NI-FGEN only reports the done parameter as True after the current generation is complete in Single trigger mode.

Return type:bool
Returns:Returns information about the completion of waveform generation.

Defined Values

True Generation is complete.
False Generation is not complete.
nifgen.Session.query_arb_seq_capabilities()

Returns the properties of the signal generator that are related to creating arbitrary sequences (the nifgen.Session.max_num_sequences, nifgen.Session.min_sequence_length, nifgen.Session.max_sequence_length, and nifgen.Session.max_loop_count properties).

Return type:tuple (maximum_number_of_sequences, minimum_sequence_length, maximum_sequence_length, maximum_loop_count)

WHERE

maximum_number_of_sequences (int):

Returns the maximum number of arbitrary waveform sequences that the signal generator allows. NI-FGEN obtains this value from the nifgen.Session.max_num_sequences property.

minimum_sequence_length (int):

Returns the minimum number of arbitrary waveforms the signal generator allows in a sequence. NI-FGEN obtains this value from the nifgen.Session.min_sequence_length property.

maximum_sequence_length (int):

Returns the maximum number of arbitrary waveforms the signal generator allows in a sequence. NI-FGEN obtains this value from the nifgen.Session.max_sequence_length property.

maximum_loop_count (int):

Returns the maximum number of times the signal generator can repeat an arbitrary waveform in a sequence. NI-FGEN obtains this value from the nifgen.Session.max_loop_count property.
nifgen.Session.query_arb_wfm_capabilities()

Returns the properties of the signal generator that are related to creating arbitrary waveforms. These properties are the maximum number of waveforms, waveform quantum, minimum waveform size, and maximum waveform size.

Note

If you do not want to obtain the waveform quantum, pass a value of VI_NULL for this parameter.

Return type:tuple (maximum_number_of_waveforms, waveform_quantum, minimum_waveform_size, maximum_waveform_size)

WHERE

maximum_number_of_waveforms (int):

Returns the maximum number of arbitrary waveforms that the signal generator allows. NI-FGEN obtains this value from the nifgen.Session.max_num_waveforms property.

waveform_quantum (int):

The size (number of points) of each waveform must be a multiple of a constant quantum value. This parameter obtains the quantum value that the signal generator uses. NI-FGEN returns this value from the nifgen.Session.waveform_quantum property.

For example, when this property returns a value of 8, all waveform sizes must be a multiple of 8.

minimum_waveform_size (int):

Returns the minimum number of points that the signal generator allows in a waveform. NI-FGEN obtains this value from the nifgen.Session.min_waveform_size property.

maximum_waveform_size (int):

Returns the maximum number of points that the signal generator allows in a waveform. NI-FGEN obtains this value from the nifgen.Session.max_waveform_size property.
nifgen.Session.query_freq_list_capabilities()

Returns the properties of the signal generator that are related to creating frequency lists. These properties are nifgen.Session.max_num_freq_lists, nifgen.Session.min_freq_list_length, nifgen.Session.max_freq_list_length, nifgen.Session.min_freq_list_duration, nifgen.Session.max_freq_list_duration, and nifgen.Session.freq_list_duration_quantum.

Return type:tuple (maximum_number_of_freq_lists, minimum_frequency_list_length, maximum_frequency_list_length, minimum_frequency_list_duration, maximum_frequency_list_duration, frequency_list_duration_quantum)

WHERE

maximum_number_of_freq_lists (int):

Returns the maximum number of frequency lists that the signal generator allows. NI-FGEN obtains this value from the nifgen.Session.max_num_freq_lists property.

minimum_frequency_list_length (int):

Returns the minimum number of steps that the signal generator allows in a frequency list. NI-FGEN obtains this value from the nifgen.Session.min_freq_list_length property.

maximum_frequency_list_length (int):

Returns the maximum number of steps that the signal generator allows in a frequency list. NI-FGEN obtains this value from the nifgen.Session.max_freq_list_length property.

minimum_frequency_list_duration (float):

Returns the minimum duration that the signal generator allows in a step of a frequency list. NI-FGEN obtains this value from the nifgen.Session.min_freq_list_duration property.

maximum_frequency_list_duration (float):

Returns the maximum duration that the signal generator allows in a step of a frequency list. NI-FGEN obtains this value from the nifgen.Session.max_freq_list_duration property.

frequency_list_duration_quantum (float):

Returns the quantum of which all durations must be a multiple in a frequency list. NI-FGEN obtains this value from the nifgen.Session.freq_list_duration_quantum property.
nifgen.Session.read_current_temperature()

Reads the current onboard temperature of the device. The temperature is returned in degrees Celsius.

Return type:float
Returns:Returns the current temperature read from onboard temperature sensors, in degrees Celsius.
nifgen.Session.reset()

Resets the instrument to a known state. This method aborts the generation, clears all routes, and resets session properties to the default values. This method does not, however, commit the session properties or configure the device hardware to its default state.

Note

For the NI 5401/5404/5411/5431, this method exhibits the same behavior as the nifgen_ResetDevice method.

nifgen.Session.reset_device()

Performs a hard reset on the device. Generation is stopped, all routes are released, external bidirectional terminals are tristated, FPGAs are reset, hardware is configured to its default state, and all session properties are reset to their default states.

nifgen.Session.reset_with_defaults()

Resets the instrument and reapplies initial user–specified settings from the logical name that was used to initialize the session. If the session was created without a logical name, this method is equivalent to the nifgen_reset method.

nifgen.Session.self_cal()

Performs a full internal self-calibration on the device. If the calibration is successful, new calibration data and constants are stored in the onboard EEPROM.

nifgen.Session.self_test()

Runs the instrument self-test routine and returns the test result(s).

Raises SelfTestError on self test failure. Properties on exception object:

  • code - failure code from driver
  • message - status message from driver
Self-Test Code Description
0 Passed self-test
1 Self-test failed

Note

When used on some signal generators, the device is reset after the nifgen.Session.self_test() method runs. If you use the nifgen.Session.self_test() method, your device may not be in its previously configured state after the method runs.

nifgen.Session.send_software_edge_trigger(trigger, trigger_id)

Sends a command to trigger the signal generator. This VI can act as an override for an external edge trigger.

Note

This VI does not override external digital edge triggers of the NI 5401/5411/5431.

Parameters:
nifgen.Session.set_named_waveform_next_write_position(waveform_name, relative_to, offset)

Sets the position in the waveform to which data is written at the next write. This method allows you to write to arbitrary locations within the waveform. These settings apply only to the next write to the waveform specified by the waveformHandle parameter. Subsequent writes to that waveform begin where the last write left off, unless this method is called again. The waveformHandle passed in must have been created with a call to one of the following methods:

  • nifgen_AllocateWaveform
  • nifgen_CreateWaveformF64
  • nifgen_CreateWaveformI16
  • nifgen_CreateWaveformFromFileI16
  • nifgen_CreateWaveformFromFileF64
  • nifgen_CreateWaveformFromFileHWS

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].set_named_waveform_next_write_position(waveform_name, relative_to, offset)
Parameters:
  • waveform_name (str) – Specifies the name to associate with the allocated waveform.
  • relative_to (nifgen.RelativeTo) –

    Specifies the reference position in the waveform. This position and offset together determine where to start loading data into the waveform.

    **Defined Values**

    START (0) Use the start of the waveform as the reference position.
    CURRENT (1) Use the current position within the waveform as the reference position.
  • offset (int) – Specifies the offset from the relativeTo parameter at which to start loading the data into the waveform.
nifgen.Session.set_waveform_next_write_position(waveform_handle, relative_to, offset)

Sets the position in the waveform at which the next waveform data is written. This method allows you to write to arbitrary locations within the waveform. These settings apply only to the next write to the waveform specified by the waveformHandle parameter. Subsequent writes to that waveform begin where the last write left off, unless this method is called again. The waveformHandle passed in must have been created by a call to the nifgen_AllocateWaveform method or one of the following niFgen CreateWaveform methods:

  • nifgen_CreateWaveformF64
  • nifgen_CreateWaveformI16
  • nifgen_CreateWaveformFromFileI16
  • nifgen_CreateWaveformFromFileF64
  • nifgen_CreateWaveformFromFileHWS

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].set_waveform_next_write_position(waveform_handle, relative_to, offset)
Parameters:
  • waveform_handle (int) – Specifies the handle of the arbitrary waveform previously allocated with the nifgen_AllocateWaveform method.
  • relative_to (nifgen.RelativeTo) –

    Specifies the reference position in the waveform. This position and offset together determine where to start loading data into the waveform.

    **Defined Values**

    START (0) Use the start of the waveform as the reference position.
    CURRENT (1) Use the current position within the waveform as the reference position.
  • offset (int) – Specifies the offset from relativeTo at which to start loading the data into the waveform.
nifgen.Session.wait_until_done(max_time=10000)

Waits until the device is done generating or until the maximum time has expired.

Parameters:max_time (float in seconds or datetime.timedelta) – Specifies the timeout value in milliseconds.
nifgen.Session.write_script(script)

Writes a string containing one or more scripts that govern the generation of waveforms.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].write_script(script)
Parameters:script (str) – Contains the text of the script you want to use for your generation operation. Refer to scripting Instructions for more information about writing scripts.
nifgen.Session.write_waveform(waveform_name_or_handle, data)

Writes data to the waveform in onboard memory.

By default, subsequent calls to this method continue writing data from the position of the last sample written. You can set the write position and offset by calling the nifgen_SetNamedWaveformNextWritePosition nifgen_SetWaveformNextWritePosition method.

Tip

This method requires repeated capabilities (usually channels). If called directly on the nifgen.Session object, then the method will use all repeated capabilities in the session. You can specify a subset of repeated capabilities using the Python index notation on an nifgen.Session instance, and calling this method on the result.:

session.channels['0,1'].write_waveform(waveform_name_or_handle, data)
Parameters: