National Instruments PXI-7340, Руководство пользователя и технические характеристики

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Glossary
G-6 | ni.com
O
open-loop Refers to a motion control system where no external sensors (feedback
devices) are used to provide position or velocity correction signals.
P
PCI peripheral component interconnect—a high-performance expansion
bus architecture originally developed by Intel to replace ISA and
EISA. It is achieving widespread acceptance as a standard for PCs and
workstations; it offers a theoretical maximum transfer rate of 132
MB/s.
port (1) A communications connection on a computer or a remote
controller. (2) A digital port, consisting of eight lines of digital input
and/or output.
position breakpoint Position breakpoint for an encoder can be set in absolute or relative
quadrature counts. When the encoder reaches a position breakpoint,
the associated breakpoint output immediately transitions.
power cycling Turning the host computer off and then back on, which causes a reset
of the motion control board.
PWM pulse width modulation—a method of controlling the average current
in a motor phase winding by varying the on-time (duty cycle) of
transistor switches.
PXI PCI eXtensions for Instrumentation
Q
quadrature counts The encoder line resolution times four.
R
RAM random-access memory
relative breakpoint Sets the position breakpoint for an encoder in relative quadrature
counts.