Glossary
© National Instruments Corporation G-7 NI PCI-5911 User Manual
pretriggering the technique used on a device to keep a buffer filled with data, so that when
the trigger conditions are met, the sample includes the data leading up
to the trigger condition
PXI PCI eXtensions for Instrumentation. PXI is an open specification that
builds off the CompactPCI specification by adding
instrumentation-specific features.
RRresistor
RAM random-access memory
real-time sampling sampling that occurs immediately
random interleaved
sampling (RIS)
method of increasing the sample rate by repetitively sampling a repeated
waveform
resolution the smallest signal increment that can be detected by a measurement
system. Resolution can be expressed in bits or in digits. The number of bits
in a system is roughly equal to 3.3 times the number of digits.
rms root mean square—a measure of signal amplitude; the square root of the
average value of the square of the instantaneous signal amplitude
ROM read-only memory
RTSI bus real-time system integration bus—the National Instruments timing bus that
connects devices directly, by means of connectors on top of the boards, for
precise synchronization of functions
Ss seconds
S samples
S/s samples per second—used to express the rate at which an instrument
samples an analog signal. 100 MS/s would equal 100 million samples each
second.