COMPUTER CONTROL and
DATA ACQUISITION
by David A. Ward
Part 1: An Introduction to National
Instruments LabVIEW Software
The ability to automate equipment and processes with
a computer is what makes many of today’s machines
appear to have a degree of intelligence. One of the
foremost companies in the world in computer control
software and hardware is National Instruments. You can
learn more about them at www.ni.com. NI has a wide
range of computer interfacing software and hardware
options. However, this series will only deal with the most
affordable of these and is intended to get the user started
in the right direction.
This month, we will get you started in computer
interfacing using NI’s LabVIEW software and hardware.
The next article will introduce NI’s USB-6008( 9) DAQ (data
acquisition) units, and the third will cover connecting the
USB units up to real world circuits. The fourth will cover
the analog-to-digital and digital-to-analog features of the
USB units. The fifth and final article will tie everything
together demonstrating how to build and program a
thermal cycling system.
Intro to LabVIEW
NI’s LabVIEW is their main software product. The
basic version retails for around $1,250. However, they do
allow a free test drive for 30 days. A less expensive way to
get LabVIEW is to purchase the USB-6008( 9) student kit for
FIGURE 1
46 SERVO 03.2009
around $170 for the 6008 unit and $280 for the 6009 unit
which includes the USB hardware unit and a student copy
of LabVIEW (part #779320-22 for the USB-6008 and part
779321-22 for the USB-6009). “LabVIEW 8 Student Edition”
by Robert H. Bishop (which includes a student copy of
LabVIEW; ISBN-10: 0131999184) can be purchased in
the Nuts & Volts webstore. Discounts are offered for
subscribers. Although you would still need to purchase the
USB-6008( 9) unit, you’d have an excellent text as well, to
help you learn how to use LabVIEW. We’ll compare the
USB-6008 and USB-6009 units in the second article.
LabVIEW is a powerful graphical programming
language that can be programmed by the user selecting
and placing icons on the work areas and then “wiring”
them together to get the results he or she desires from the
software. NI refers to programs built in LabVIEW as “VIs” or
virtual instruments. These VIs allow you to gather and store
data and display information in graphs, charts, and through
other methods. The VIs also allow the user to control
external devices, turning them on and off as desired.
Hello World!
Let’s go through the process of making a very simple
VI at this time. You won’t need any external hardware
connected to your computer right now. The purpose of this
FIGURE 2
