niFgen_ConfigureStandardWaveform

NI-FGEN C Function

niFgen_ConfigureStandardWaveform

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

Purpose

Configures the attributes of the signal generator that affect standard waveform generation (the NIFGEN_ATTR_FUNC_WAVEFORM, NIFGEN_ATTR_FUNC_AMPLITUDE, NIFGEN_ATTR_FUNC_DC_OFFSET, NIFGEN_ATTR_FUNC_FREQUENCY, and NIFGEN_ATTR_FUNC_START_PHASE attributes).

Note  You must use 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 the niFgen_init or the niFgen_InitWithOptions 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_ATTR_FUNC_WAVEFORM attribute to this value.

Defined Values

NIFGEN_VAL_WFM_SINE Sinusoidal waveform
NIFGEN_VAL_WFM_SQUARE Square waveform
NIFGEN_VAL_WFM_TRIANGLE Triangular waveform
NIFGEN_VAL_WFM_RAMP_UP Positive ramp waveform
NIFGEN_VAL_WFM_RAMP_DOWN Negative ramp waveform
NIFGEN_VAL_WFM_DC Constant voltage
NIFGEN_VAL_WFM_NOISE White noise
NIFGEN_VAL_WFM_USER User-defined waveform as defined with the niFgen_DefineUserStandardWaveform function

Default Value: NIFGEN_VAL_WFM_SINE

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_ATTR_FUNC_AMPLITUDE attribute to this value.

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

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.

Units: peak-to-peak voltage

Default Value: None

dcOffset ViReal64 Specifies the DC offset of the standard waveform that you want the signal generator to produce. This value is the offset at the output terminal (the offset is from ground to the center of the waveform). NI-FGEN sets the NIFGEN_ATTR_FUNC_DC_OFFSET attribute to this value.

For example, to configure a waveform with an amplitude of 10.00 V to range from 0.00 to +10.00 V, set the DC Offset to 5.00 V.

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_ATTR_FUNC_FREQUENCY attribute to this value.

Notes  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.

Units: hertz

Default Value: None

startPhase ViReal64 Specifies the horizontal offset of the standard waveform you want the signal generator to produce. Specify this attribute in degrees of one waveform cycle. NI-FGEN sets the NIFGEN_ATTR_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.
Note   This parameter does not affect signal generator behavior when you set the waveform parameter to NIFGEN_VAL_WFM_DC.

Units: degrees of one cycle

Default Value: 0.00

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