National Instruments 6023E User Manual
Page 124
Glossary
© National Instruments Corporation
G-11
SISOURCE
SI counter clock signal
software trigger
a programmed event that triggers an event such as data acquisition
software triggering
a method of triggering in which you simulate an analog trigger using
software. Also called conditional retrieval.
SOURCE
source signal
S/s
samples per second—used to express the rate at which a DAQ board
samples an analog signal
STARTSCAN
start scan signal
STC
system timing controller
synchronous
(1) hardware—a property of an event that is synchronized to a reference
clock (2) software—a property of a function that begins an operation and
returns only when the operation is complete
T
TC
terminal count—the highest value of a counter
THD
total harmonic distortion
THD+N
signal-to-THD plus noise—the ratio in decibels of the overall rms signal to
the rms signal of harmonic distortion plus noise introduced
TRIG
trigger signal
trigger
any event that causes or starts some form of data capture
TTL
transistor-transistor logic
U
UI
update interval
unipolar
a signal range that is always positive (for example, 0 to +10 V)
UISOURCE
update interval counter clock signal