User manual

Chapter 3 Software Overview
© National Instruments Corporation 3-21 NI-DAQ User Manual for PC Compatibles
SCAN_Op
Performs a synchronous, multiple-channel
scanned data acquisition operation.
SCAN_Op
does not return until NI-DAQ has
acquired all the data or an acquisition error
has occurred.
SCAN_to_Disk
Performs a synchronous, multiple-channel
scanned data acquisition operation and
simultaneously saves the acquired data in a
disk file.
SCAN_to_Disk
does not return
until NI-DAQ has acquired all the data and
saved it or until an acquisition error has
occurred.
Low-Level Data Acquisition Functions
These functions are low-level primitives used for setting up, starting, and
monitoring asynchronous data acquisition operations.
Refer to the NI-DAQ Function Reference Online Help file to determine
which functions your device supports.
DAQ_Check
Checks if the current data acquisition
operation is complete and returns the status
and the number of samples acquired to that
point.
DAQ_Clear
Cancels the current data acquisition
operation (both single-channel and
multiple-channel scanned) and reinitializes
the data acquisition circuitry.
DAQ_Config
Stores configuration information for
subsequent data acquisition operations.
DAQ_Monitor
Returns data from an asynchronous
data acquisition in progress. During a
multiple-channel acquisition, you can call
DAQ_Monitor
to retrieve data from a
single channel or from all channels being
scanned. Using the oldest/newest mode,
you can specify whether
DAQ_Monitor
returns sequential (oldest) blocks of data,
or the most recently acquired (newest)
blocks of data.