Glossary
©
National Instruments Corporation
G-9
PFI6/WFTRIG
PFI6/waveform trigger
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 communications connection on a computer or a remote controller;
(2) a digital port, consisting of four or eight lines of digital input and/or
output
ppm
parts per million
pu
pull-up
PXI
PCI eXtenstions for Instrumentation—a rugged, open system for modular
instrumentation based on CompactPCI, with special mechanical, electrical,
and software features. The PXIbus standard was originally developed by
National Instruments in 1997, and it is now managed by the PXIbus
Systems Alliance.
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.
reglitch
circuitry used on analog outputs to generate uniform glitch energy at every
code rather than large glitches at the major code transitions. This uniform
glitch energy appears as a multiple of the update rate in the frequency
spectrum.
rms
root mean square—the square root of the average value of the square of the
instantaneous signal amplitude; a measure of signal amplitude
RSE
referenced single-ended mode—all measurements are made with respect
to a common reference measurement system or a ground. Also called a
grounded measurement system.