NI FGEN Standard Output Functions

Standard Output Functions

• niFgen_ConfigureStandardWaveform
• niFgen_DefineUserStandardWaveform
• niFgen_ClearUserStandardWaveform
• niFgen_ConfigureFrequency
• niFgen_ConfigureAmplitude

niFgen_ConfigureStandardWaveform

ViStatus niFgen_ConfigureStandardWaveform (ViSession vi, ViConstString channelName, ViInt32 waveform, ViReal64 amplitude, ViReal64 dcOffset, ViReal64 frequency, ViReal64 startPhase);

Purpose

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

• NIFGEN_ATTRIBUTE_FUNC_WAVEFORM
• NIFGEN_ATTRIBUTE_FUNC_AMPLITUDE
• NIFGEN_ATTRIBUTE_FUNC_DC_OFFSET
• NIFGEN_ATTRIBUTE_FUNC_FREQUENCY
• NIFGEN_ATTRIBUTE_FUNC_START_PHASE

Note:  You must call the niFgen_ConfigureOutputMode function with the outputMode parameter set to NIFGEN_VAL_OUTPUT_FUNC before calling this function.

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from theniFgen_init, niFgen_InitWithOptions, or niFgen_InitializeWithChannels functions and identifies a particular instrument session.
channelName	ViConstString	Specifies the channel name for which you want to configure a standard waveform. Default Value: "0"
waveform	ViInt32	Specifies the standard waveform that you want the signal generator to produce. NI-FGEN sets the NIFGEN_ATTRIBUTE_FUNC_WAVEFORM attribute to this value. Default Value: NIFGEN_VAL_WFM_SINE Defined Values

NIFGEN_VAL_WFM_SINE	Specifies that the signal generator produces a sinusoid waveform.
NIFGEN_VAL_WFM_SQUARE	Specifies that the signal generator produces a square waveform.
NIFGEN_VAL_WFM_TRIANGLE	Specifies that the signal generator produces a triangle waveform.
NIFGEN_VAL_WFM_RAMP_UP	Specifies that the signal generator produces a positive ramp waveform.
NIFGEN_VAL_WFM_RAMP_DOWN	Specifies that the signal generator produces a negative ramp waveform.
NIFGEN_VAL_WFM_DC	Specifies that the signal generator produces a constant voltage.
NIFGEN_VAL_WFM_NOISE	Specifies that the signal generator produces white noise.
NIFGEN_VAL_WFM_USER	Specifies that the signal generator produces a user-defined waveform as defined with the niFgen_DefineUserStandardWaveform function.

Name	Type	Description
amplitude	ViReal64	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_ATTRIBUTE_FUNC_AMPLITUDE attribute 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_ConfigureStandardWaveform function to NIFGEN_VAL_WFM_DC.
dcOffset	ViReal64	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_ATTRIBUTE_FUNC_DC_OFFSETattribute to this value. Units: volts Default Value: None
frequency	ViReal64	Specifies the frequency of the standard waveform that you want the signal generator to produce. NI-FGEN sets the NIFGEN_ATTRIBUTE_FUNC_FREQUENCY attribute 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_ConfigureStandardWaveform function to NIFGEN_VAL_WFM_DC. Frequency ranges vary from device to device. For information about the frequencies supported on your device, refer to the Features Supported topic for your device in the NI Signal Generators Help.
startPhase	ViReal64	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_ATTRIBUTE_FUNC_START_PHASE attribute 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 NIFGEN_VAL_WFM_DC.

Return Value

Name	Type	Description
status	ViStatus	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. You can examine the status code from each call to an NI-FGEN function to determine if an error occurred. To obtain a text description of the status code, call the niFgen_error_message function. To obtain additional information about the error condition, call the niFgen_GetError function. To clear the error information from NI-FGEN, call the niFgen_ClearError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors

niFgen_DefineUserStandardWaveform

ViStatus niFgen_DefineUserStandardWaveform (ViSession vi, ViConstString channelName, ViInt32 waveformSize, ViReal64[] waveformDataArray);

Purpose

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

To select the waveform, set the waveform parameter to NIFGEN_VAL_WFM_USER with either the niFgen_ConfigureStandardWaveform or the niFgen_CreateFreqList function.

The waveform data must be scaled between –1.0 and 1.0. Use the amplitude parameter in the niFgen_ConfigureStandardWaveform function to generate different output voltages.

Note:  You must call the niFgen_ConfigureOutputMode function to set the outputMode parameter to NIFGEN_VAL_OUTPUT_FUNC or NIFGEN_VAL_OUTPUT_FREQ_LIST before calling this function.

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from theniFgen_init, niFgen_InitWithOptions, or niFgen_InitializeWithChannels functions and identifies a particular instrument session.
channelName	ViConstString	Specifies the channel name for which you want to define a user standard waveform. Default Value: "0"
waveformSize	ViInt32	Specifies the size of the waveform in samples. Default Value: 16384
waveformDataArray	ViReal64[]	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

Return Value

Name	Type	Description
status	ViStatus	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. You can examine the status code from each call to an NI-FGEN function to determine if an error occurred. To obtain a text description of the status code, call the niFgen_error_message function. To obtain additional information about the error condition, call the niFgen_GetError function. To clear the error information from NI-FGEN, call the niFgen_ClearError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors

niFgen_ClearUserStandardWaveform

ViStatus niFgen_ClearUserStandardWaveform (ViSession vi, ViConstString channelName);

Purpose

Clears the user-defined waveform created by the niFgen_DefineUserStandardWaveform function.

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from theniFgen_init, niFgen_InitWithOptions, or niFgen_InitializeWithChannels functions and identifies a particular instrument session.
channelName	ViConstString	Specifies the channel name from which you want to clear a user standard waveform. Default Value: "0"

Return Value

Name	Type	Description
status	ViStatus	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. You can examine the status code from each call to an NI-FGEN function to determine if an error occurred. To obtain a text description of the status code, call the niFgen_error_message function. To obtain additional information about the error condition, call the niFgen_GetError function. To clear the error information from NI-FGEN, call the niFgen_ClearError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors

niFgen_ConfigureFrequency

ViStatus niFgen_ConfigureFrequency (ViSession vi, ViConstString channelName, ViReal64 frequency);

Purpose

Configures the frequency of the standard waveform that you want the signal generator to produce.

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from theniFgen_init, niFgen_InitWithOptions, or niFgen_InitializeWithChannels functions and identifies a particular instrument session.
channelName	ViConstString	Specifies the channel name for which you want to configure a standard waveform. Default Value: "0"
frequency	ViReal64	Specifies the frequency of the standard waveform that you want the signal generator to produce. NI-FGEN sets the NIFGEN_ATTRIBUTE_FUNC_FREQUENCY attribute 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_ConfigureStandardWaveform function to NIFGEN_VAL_WFM_DC. Frequency ranges vary from device to device. For information about the frequencies supported on your device, refer to the Features Supported topic for your device in the NI Signal Generators Help.

Return Value

Name	Type	Description
status	ViStatus	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. You can examine the status code from each call to an NI-FGEN function to determine if an error occurred. To obtain a text description of the status code, call the niFgen_error_message function. To obtain additional information about the error condition, call the niFgen_GetError function. To clear the error information from NI-FGEN, call the niFgen_ClearError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors

niFgen_ConfigureAmplitude

ViStatus niFgen_ConfigureAmplitude (ViSession vi, ViConstString channelName, ViReal64 amplitude);

Purpose

Configures the amplitude of the standard waveform that you want the signal generator to produce.

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from theniFgen_init, niFgen_InitWithOptions, or niFgen_InitializeWithChannels functions and identifies a particular instrument session.
channelName	ViConstString	Specifies the channel name for which you want to configure a standard waveform. Default Value: "0"
amplitude	ViReal64	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_ATTRIBUTE_FUNC_AMPLITUDE attribute 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_ConfigureStandardWaveform function to NIFGEN_VAL_WFM_DC.

Return Value

Name	Type	Description
status	ViStatus	Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. You can examine the status code from each call to an NI-FGEN function to determine if an error occurred. To obtain a text description of the status code, call the niFgen_error_message function. To obtain additional information about the error condition, call the niFgen_GetError function. To clear the error information from NI-FGEN, call the niFgen_ClearError function. The general meaning of the status code is as follows:

Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors