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Glossary
© National Instruments Corporation
G-13
Getting Started with Your PCI/PXI-6810 SDA
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
posttriggering
the technique used on an instrument to acquire a programmed number
of samples after trigger conditions are met
ppm
parts per million
pretriggering
the technique used on an instrument to keep a continuous buffer filled
with data, so that when the trigger conditions are met, the sample
includes the data leading up to the trigger condition
propagation
the transmission of a signal through a computer system
propagation delay
the amount of time required for a signal to pass through a circuit
protocol
the exact sequence of bits, characters, and control codes used to transfer
data between computers and peripherals through a communications
channel.
pts
points
pulse trains
multiple pulses
pulsed output
a form of counter signal generation by which a pulse is outputted when
a counter reaches a certain value
PXI
Stands for PCI eXtensions for Instrumentation. PXI is an open
specification that builds off the CompactPCI specification by adding
instrumentation-specific features.
R
RAM
random-access memory
RD
Read Data signal
real time
a property of an event or system in which data is processed as it is
acquired instead of being accumulated and processed at a later time
resolution
the smallest signal increment that can be detected by a measurement
system. Resolution can be expressed in bits, in proportions, or in a