National Instruments 6023E User Manual
Page 122
Glossary
© National Instruments Corporation
G-9
PFI7/STARTSCAN
PFI7/start of scan
PFI8/GPCTR0_
SOURCE
PFI8/general purpose counter 0 source
PFI9/GPCTR0_GATE
PFI9/general purpose counter 0 gate
PGIA
programmable gain instrumentation amplifier
port
(1) a digital port consisting of multiple I/O lines on a DAQ device
(2) a serial or parallel interface connector on a PC
PPI
programmable peripheral interface
ppm
parts per million
pu
pullup
pulse trains
multiple pulses
Q
quantization error
the inherent uncertainty in digitizing an analog value due to the finite
resolution of the conversion process
R
referenced signal
sources
signal sources with voltage signals that are referenced to a system ground,
such as the earth or a building ground. Also called grounded signal sources.
resolution
the smallest signal increment that can be detected by a measurement
system. Resolution can be expressed in bits, in proportions, or in percent
of full scale. For example, a system has 12-bit resolution, one part in
4,096 resolution, and 0.0244% of full scale.
ribbon cable
a flat cable in which the conductors are side by side
rise time
the difference in time between the 10% and 90% points of a system’s step
response
rms
root mean square—the square root of the average value of the square of the
instantaneous signal amplitude; a measure of signal amplitude