National Instruments NI 6120 User Manual
Page 113
Glossary
G-8
ni.com
N
NC
not connected (signal)
NI
National Instruments
NI-DAQ
National Instruments driver software for DAQ hardware
noise
an undesirable electrical signal from external sources such as the AC
power line, motors, generators, transformers, fluorescent lights, soldering
irons, CRT displays, computers, electrical storms, welders, radio
transmitters, and internal sources such as semiconductors, resistors, and
capacitors; noise corrupts signals you are trying to send or receive
nonreferenced signal
sources
signal sources, including batteries, transformers, or thermocouples, with
voltage signals that are not connected to an absolute reference or system
ground; also called nonreferenced signal sources
Nyquist frequency
the maximum signal frequency that a sampling system can accurately
represent in frequency spectrum measurement, which is half the sampling
frequency
O
OUT
output pin—a counter output pin where the counter can generate various
TTL pulse waveforms
P
PCI
Peripheral Component Interconnect—a high-performance expansion
bus architecture originally developed by Intel to replace ISA and EISA;
is achieving widespread acceptance as a standard for PCs and
work-stations, and offers a theoretical maximum transfer rate of
132 Mbytes/s
pd
pull down
PFI
programmable function input
PFI0/TRIG1
PFI0/trigger 1
PFI1/TRIG2
PFI1/trigger 2