Glossary
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National Instruments Corporation
G-11
t
p
pulse period
TRIG
trigger signal
trigger
any event that causes or starts some form of data capture
t
sc
source clock period
t
sp
source pulse width
TTL
transistor-transistor logic—a digital circuit composed of bipolar transistors
wired in a certain manner
t
w
pulse width
two’s complement
given a number
x
expressed in base 2 with
n
digits to the left of the radix
point, the (base 2) number 2
n
–
x
U
UI
update interval
UISOURCE
update interval counter clock signal
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
AO channel in the group.
update rate
the number of output updates per second
V
V
volts
V
CC
positive supply voltage
VDC
volts direct current
V
IH
volts, input high
V
IL
volts, input low
