Programming instructions

Glossary
© National Instruments Corporation G-15 LabVIEW Data Acquisition Basics Manual
TC Terminal count. The highest value of a counter.
toggled output A form of counter signal generation by which the output changes the state
of the output signal from high to low, or low to high when the counter
reaches a certain value.
top-level VI VI at the top of the VI hierarchy. This term is used to distinguish the VI
from its subVIs.
track-and-hold A circuit that tracks an analog voltage and holds the value on command.
transducer excitation A type of signal conditioning that uses external voltages and currents to
excite the circuitry of a signal conditioning system into measuring physical
phenomena.
trigger Any event that causes or starts some form of data capture.
U
unipolar A signal range that is either always positive or negative, but never both
(for example 0 to 10 V,
not
–10 to 10 V).
update 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 rate The number of output updates per second.
update width The number of channels in the channel list or number of ports in the port
list you use to configure an analog or digital output group.
V
V Volts.
VDC Volts, Direct Current.
VI Virtual Instrument. A LabVIEW program; so-called because it models the
appearance and function of a physical instrument.
Voltage reference. V
ref