National Instruments NI USB-621x - Manual (Page 13)

© National Instruments Corporation xiii NI USB-621x User Manual
About This Manual
The NI 621x User Manual contains information about using the National
Instruments USB-621x data acquisition (DAQ) devices with
NI-DAQmx 8.3 and later. NI 621x devices feature up to 32 analog input
(AI) channels, up to two analog output (AO) channels, up to eight lines of
digital input (DI), up to eight lines of digital output (DO), and two counters.
Conventions
The following conventions are used in this manual:
<> Angle brackets that contain numbers separated by an ellipsis represent
a range of values associated with a bit or signal name—for example,
AO <3..0>.
» The » symbol leads you through nested menu items and dialog box options
to a final action. The sequence File»Page Setup»Options directs you to
pull down the File menu, select the Page Setup item, and select Options
from the last dialog box.
This icon denotes a note, which alerts you to important information.
This icon denotes a caution, which advises you of precautions to take to
avoid injury, data loss, or a system crash.
When this symbol is marked on a
product, refer to the Read Me First: Safety and Radio-Frequency
Interference document which can be found at
ni.com/manuals , for
information about precautions to take.
bold Bold text denotes items that you must select or click in the software, such
as menu items and dialog box options. Bold text also denotes parameter
names.
italic Italic text denotes variables, emphasis, a cross-reference, or an introduction
to a key concept. Italic text also denotes text that is a placeholder for a word
or value that you must supply.
monospace Text in this font denotes text or characters that you should enter from the
keyboard, sections of code, programming examples, and syntax examples.
This font is also used for the proper names of disk drives, paths, directories,
programs, subprograms, subroutines, device names, functions, operations,
variables, filenames, and extensions.