niRFSA_FetchIQMultiRecordComplexF64

niRFSA_FetchIQMultiRecordComplexF64

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

Purpose

Fetches I/Q data from multiple records in an acquisition. A fetch transfers acquired waveform data from device memory to computer memory. The data was acquired to onboard memory previously by the hardware after the acquisition was initiated.

This function is not necessary if you use the niRFSA_ReadIQSingleRecordComplexF64 function because the niRFSA_ReadIQSingleRecordComplexF64 function performs the fetch as part of the function.

Supported Devices: PXIe-5644/5645/5646, PXI-5661, PXIe-5663/5663E/5665/5667/5668, PXIe-5820/5830/5831/5832/5840/5841/5842/5860

Related Topics

None (Trigger Type)

Parameters

Input
Name	Type	Description
vi	ViSession	Identifies your instrument session. vi is obtained from the niRFSA_init or niRFSA_InitWithOptions function.
channelList	ViConstString	Identifies which channels to apply settings. Specify an empty string as the value of this parameter.
startingRecord	ViInt64	Specifies the first record to retrieve. Record numbers are zero-based. The default value is 0.
numberOfRecords	ViInt64	Specifies the number of records to fetch.
numberOfSamples	ViInt64	Specifies the number of samples per record.
timeout	ViReal64	PXI-5661, PXIe-5663/5665/5667—Specifies the time, in seconds, allotted for the function to complete before returning a timeout error. PXIe-5644/5645/5646, PXIe-5668, PXIe-5820/5830/5831/5832/5840/5841/5842/5860—Specifies the time, in seconds, allotted to receive the reference trigger. Note  For all supported devices, a value of –1 specifies the function waits until all data is available. A value of 0 specifies the function immediately returns available data.
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*	Contains the absolute and relative timestamps for the operation, the time interval (dt), and the actual number of samples read. Each element of this array corresponds to a record. The following list provides more information about each of these properties: absolute timestamp—Returns the timestamp, in seconds, of the first fetched sample that is comparable between records and acquisitions. Note  The value of the absolute timestamp returned is always 0 for the PXIe-5644/5645/5646, PXIe-5668, and PXIe-5820/5840/5841/5842/5860. relative timestamp—Returns a timestamp that corresponds to the difference, in seconds, between the first sample returned and the Reference Trigger location. The timestamp is zero if the Reference Trigger has not occurred. Note  The value of the relative timestamp returned is always 0 for the PXIe-5644/5645/5646. dt—Returns the time interval between data points in the acquired signal. The I/Q data sample rate is the reciprocal of this value. actual samples read—Returns an integer representing the number of samples in the waveform. Note  The actual number of samples for each record can vary if the NIRFSA_ATTR_NUMBER_OF_SAMPLES attribute changes per step during RF list mode. offset—Returns the offset to scale data, (b), in mx + b form. gain—Returns the gain to scale data, (m), in mx + b form.

Return Value