National Instruments NI PXI-4220, Руководство пользователя

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Glossary
© National Instruments Corporation G-9 NI PXI-4220 User Manual
RSE See referenced single-ended configuration .
RTSI bus real-time system integration bus—the NI timing bus that connects DAQ
devices directly, for precise synchronization of functions.
S
s seconds
S samples
S/s samples per second—used to express the rate at which a DAQ device
samples an analog signal
sample counter the clock that counts the output of the channel clock, in other words, the
number of samples taken. On devices with SS/H, this counter counts the
output of the scan clock and hence the number of scans.
scan one or more analog or digital input samples. Typically, the number of input
samples in a scan is equal to the number of channels in the input group. For
example, one pulse from the scan clock produces one scan which acquires
one new sample from every analog input channel in the group.
scan clock the clock controlling the time interval between scans
scan interval controls how often a scan is initialized. The scan interval is regulated by
AI SAMP CLK.
scan rate reciprocal of the scan interval
self-calibrating a property of a DAQ device that has an extremely stable onboard reference
and calibrates its own A/D and D/A circuits without manual adjustments by
the user
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
software trigger a programmed event that triggers an event such as DAQ
SS/H simultaneous sample-and-hold
STC system timing controller