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National Instruments Network Device DAQ S User Manual

Page 162

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Glossary

© National Instruments Corporation

G-9

NI 6124/6154 User Manual

S

s

Seconds.

S

Samples.

S/s

Samples per second—used to express the rate at which a digitizer or D/A
converter or DAQ device samples an analog signal.

scatter-gather

The term used to describe very high-speed DMA burst-mode transfers that
are made only by the bus master, and where noncontiguous blocks of
memory are transparently mapped by the controller to appear as a seamless
piece of memory.

SCXI

Signal Conditioning eXtensions for Instrumentation—the National
Instruments product line for conditioning low-level signals within an
external chassis near sensors so that only high-level signals are sent to DAQ
devices in the noisy PC environment. SCXI is an open standard available
for all vendors.

sensor

A device that responds to a physical stimulus (heat, light, sound, pressure,
motion, flow, and so on) and produces a corresponding electrical signal.

settling time

The amount of time required for a voltage to reach its final value within
specified limits.

signal conditioning

The manipulation of signals to prepare them for digitizing.

SOURCE

Source signal.

system noise

A measure of the amount of noise seen by an analog circuit or an ADC
when the analog inputs are grounded.

T

task

NI-DAQmx—a collection of one or more channels, timing, and triggering
and other properties that apply to the task itself. Conceptually, a task
represents a measurement or generation you want to perform.

terminal count

The highest value of a counter.

t

gh

Gate hold time.

t

gsu

Gate setup time.