niFgen_ConfigureArbWaveform

NI-FGEN C Function

niFgen_ConfigureArbWaveform

ViStatus niFgen_ConfigureArbWaveform (ViSession vi, ViConstString channelName, ViInt32 waveformHandle, ViReal64 gain, ViReal64 offset);

Purpose

Configures the attributes of the signal generator that affect arbitrary waveform generation (the NIFGEN_ATTR_ARB_WAVEFORM_HANDLE, NIFGEN_ATTR_ARB_GAIN, and NIFGEN_ATTR_ARB_OFFSET attributes).

Notes  The signal generator must not be in the Generating state when you call this function.
You must call the niFgen_ConfigureOutputMode function to set the output mode to NIFGEN_VAL_OUTPUT_ARB 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 an arbitrary waveform.

Default Value: "0"

waveformHandle ViInt32 Specifies the handle of the arbitrary waveform you want the signal generator to produce. NI-FGEN sets the NIFGEN_ATTR_ARB_WAVEFORM_HANDLE attribute to this value. You can create an arbitrary waveform using one of the following niFgen Create Waveform functions:

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

Default Value: None

gain ViReal64 Specifies the factor by which the signal generator scales 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 scale the arbitrary waveform to other ranges. NI-FGEN sets the NIFGEN_ATTR_ARB_GAIN attribute to this value.

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

Units: volts

Default Value: None

offset ViReal64 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_ATTR_ARB_OFFSET attribute 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

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