niRFSA_FetchIQMultiRecordComplexF64

ViStatus = niRFSA_FetchIQMultiRecordComplexF64( ViSession vi, ViConstString channelList, ViInt64 startingRecord, ViInt64 numberOfRecords, ViInt64 numberOfSamples, ViReal64 timeout, NIComplexNumber* data, niRFSA_wfmInfo* wfmInfo);

Purpose

Fetches IQ data from multiple records in an acquisition. A fetch transfers acquired waveform data from device memory to PC memory. The data was acquired to onboard memory previously by the hardware after it was initiated.

This function is not necessary if you use the niRFSA_ReadIQSingleRecordComplexF64 function, as the fetch is performed as part of that function.

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from the niRFSA_init or the niRFSA_initWithOptions functions and identifies a particular instrument session.
channelList	ViConstString	Specifies channels from which to fetch data.
startingRecord	ViInt64	Specifies the first record to retrieve.
numberOfRecords	ViInt64	Specifies the number of records to fetch. A value of -1 specifies that NI-RFSA fetches all records in an acquisition starting with the record specified by startingRecord. Record numbers are zero-indexed.
numberOfSamples	ViInt64	Specifies the number of samples per record.
timeout	ViReal64	Specifies in seconds the time allotted for the function to complete before returning a timeout error. A value of -1 specifies the function waits until all data is available. A value of 0 specifies the function returns available data immediately.
Output
Name	Type	Description
data	NIComplexNumber*	Returns the acquired waveform for each record fetched. The waveforms are written sequentially in the array. Allocate an array at least as large as numberOfSamples times numberOfRecords for this parameter.
wfmInfo	niRFSA_wfmInfo*	Returns an array of structures containing information about each record fetched. Each structure contains the absolute and relative timestamp, the dt, and the actual number of samples read for the corresponding record. The following list provides more information about each of these properties: absolute timestamp—specifies the timestamp in seconds of the first fetched sample that is comparable between records and acquisitions. relative timestamp—returns a timestamp that corresponds to the difference in seconds between the first sample returned and the Reference trigger location. dt—returns the time interval between data points in the acquired signal. The IQ data sampling rate is the reciprocal of this value. actual samples read—returns an integer representing the number of samples in the waveform. offset—specifies the offset to scale data in mx+b form. gain—specifies the gain to scale data in mx+b form. Note  Allocate an array of structures at least as large as numberOfRecords for this parameter.

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 examine the status code from each call to an instrument driver function to determine if an error occurred. To obtain a text description of the status code, call the niRFSA_error_message function. To obtain additional information about the error condition, call the niRFSA_GetError function. To clear the error information from the driver, call the niRFSA_ClearError function. The general meaning of the status code is as follows: Value	Meaning
0	Success
Positive Values	Warnings
Negative Values	Errors