Programming instructions

Glossary
LabVIEW Data Acquisition Basics Manual G-8
© National Instruments Corporation
hex Hexadecimal.
Hz Hertz. The number of scans read or updates written per second.
I
IEEE Institute of Electrical and Electronic Engineers.
immediate digital I/O A type of digital acquisition/generation where LabVIEW updates the
digital lines or port states immediately or returns the digital value of an
input line.
Also called
nonlatched digital I/O.
input limits The upper and lower voltage inputs for a channel. You must use a pair of
numbers to express the input limits. The VIs can infer the input limits from
the input range, input polarity, and input gain(s). Similarly, if you wire the
input limits, range, and polarity, the VIs can infer the onboard gains when
you do not use SCXI.
input range The difference between the maximum and minimum voltages an analog
input channel can measure at a gain of 1. The input range is a scalar value,
not a pair of numbers. By itself the input range does not uniquely determine
the upper and lower voltage limits. An input range of 10 V could mean an
upper limit of +10 V and a lower of 0 V or an upper limit of +5 V and a
lower limit of –5 V.
The combination of input range, polarity, and gain determines the input
limits of an analog input channel. For some boards, jumpers set the input
range and polarity, while you can program them for other boards. Most
boards have programmable gains. When you use SCXI modules, you also
need their gains to determine the input limits.
interrupt A signal indicating that the central processing unit should suspend its
current task to service a designated activity.
interval scanning Scanning method where there is a longer interval between scans than there
is between individual channels comprising a scan.
I/O Input/output. The transfer of data to or from a computer system involving
communications channels, operator interface devices, and/or data
acquisition and control interfaces.
ISA Industry Standard Architecture.