niFgen_SetNamedWaveformNextWritePosition

NI-FGEN C Function

niFgen_SetNamedWaveformNextWritePosition

ViStatus niFgen_SetNamedWaveformNextWritePosition (ViSession vi, ViConstString channelName, ViConstString waveformName, ViInt32 relativeto, ViInt32 offset);

Purpose

Sets the position in the waveform to which data is written at the next write. This function 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 function is called again. The waveformHandle passed in must have been created with a call to one of the following functions:

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 onto which the waveform data should be loaded.

Default Value: "0"

waveformName ViConstString Specifies the name to associate with the allocated waveform.

relativeTo ViInt32 Specifies the reference position in the waveform. The position and offset together determine where to start loading data into the waveform.

Defined Values

NIFGEN_VAL_WAVEFORM_POSITION_START (0) Use the start of the waveform as the reference position.
NIFGEN_VAL_WAVEFORM_POSITION_CURRENT (1) Use the current position within the waveform as the reference position.
offset ViInt32 Specifies the offset from the relativeTo parameter at which to start loading the data into the waveform.

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