National Instruments VXI-MIO Series - Manual (Page 139)

Glossary
 National Instruments Corporation G-15 VXI-MIO Series User Manual
U
UI update interval
UISOURCE update interval counter clock signal
unipolar Unipolar input means that the input voltage range is between 0
and V
ref
, where V
ref
is a positive reference voltage.
update The output equivalent of a scan. One or more analog or digital
output samples. Typically, the number of output samples in an
update is equal to the number of channels in the output group. For
example, one pulse from the update clock produces one update
which sends one new sample to every analog output channel in the
group.
UPDATE update signal
update rate The number of output updates per second.
V
V volts
VDC volts direct current
VI Virtual Instrument—(1) A combination of hardware and/or
software elements, typically used with a PC, that has the
functionality of a classic stand-alone instrument. (2) A LabVIEW
software module (VI), which consists of a front panel user
interface and a block diagram program.
VISA A new driver software architecture developed by National
Instruments to unify instrumentation software (GPIB, DAQ, and
VXI). It has been accepted as a standard for VXI by the
VXI
plug&play Systems Alliance.
V
IH
volts, input high
V
IL
volts, input low
V
in
volts in
V
OH
volts, output high
V
OL
volts, output low
V
ref
reference voltage