Chapter 1
Introduction
©
National Instruments Corporation
1-3
LabVIEW. The LabVIEW Data Acquisition VI Library is functionally
equivalent to the NI-DAQ software.
LabWindows/CVI features interactive graphics, a state-of-the-art user
interface, and uses the ANSI standard C programming language. The
LabWindows/CVI Data Acquisition Library, a series of functions for using
LabWindows/CVI with National Instruments DAQ hardware, is included
with the NI-DAQ software kit. The LabWindows/CVI Data Acquisition
Library is functionally equivalent to the NI-DAQ software.
VirtualBench features VIs that combine DAQ products, software, and
your computer to create a stand-alone instrument with the added benefit
of the processing, display, and storage capabilities of your computer.
VirtualBench instruments load and save waveform data to disk in the same
forms that can be used in popular spreadsheet programs and word
processors.
Using ComponentWorks, LabVIEW, LabWindows/CVI, or VirtualBench
software will greatly reduce the development time for your data acquisition
and control application.
NI-DAQ Driver Software
The NI-DAQ driver software is included at no charge with all National
Instruments DAQ hardware. NI-DAQ is not packaged with SCXI or
accessory products, except for the SCXI-1200. NI-DAQ has an extensive
library of functions that you can call from your application programming
environment. These functions include routines for analog input (A/D
conversion), buffered data acquisition (high-speed A/D conversion),
analog output (D/A conversion), waveform generation (timed D/A
conversion), digital I/O, counter/timer operations, SCXI, RTSI,
self-calibration, messaging, and acquiring data to memory.
NI-DAQ has both high-level DAQ I/O functions for maximum ease of
use and low-level DAQ I/O functions for maximum flexibility and
performance. Examples of high-level functions are streaming data to disk
or acquiring a certain number of data points. An example of a low-level
function is writing directly to registers on the DAQ device. NI-DAQ does
not sacrifice the performance of National Instruments DAQ devices
because it lets multiple devices operate at their peak performance.
NI-DAQ also internally addresses many of the complex issues between
the computer and the DAQ hardware such as programming interrupts and
DMA controllers. NI-DAQ maintains a consistent software interface
among its different versions so that you can change platforms with