Glossary
© National Instruments Corporation
G-17
Getting Started with Your PCI/PXI-6810 SDA
U
UART
universal asynchronous receiver/transmitter—an integrated circuit that
converts parallel data to serial data (and vice versa), commonly used as
a computer bus to serial device interface for serial communication
UI
update interval
unipolar
a signal range that is always positive (for example, 0 to +10 V)
update
the output equivalent of a scan. One or more analog or digital output
samples. Typically, the number of output samples in an update is equal
to the number of channels in the output group. For example, one pulse
from the update clock produces one update that sends one new sample
to every analog output channel in the group.
update rate
the number of output updates per second
V
V
volts
V
DC
volts direct current
VDMAD
virtual DMA driver
VI
virtual instrument—(1) a combination of hardware and/or software
elements, typically used with a PC, that has the functionality of a classic
stand-alone instrument (2) a LabVIEW software module (VI), which
consists of a front panel user interface and a block diagram program
V
IH
volts, input high
V
IL
volts, input low
V
in
volts in
VISA
virtual instrument software architecture—a new driver software
architecture developed by National Instruments to unify
instrumentation software GPIB, DAQ, and VXI. It has been accepted as
a standard for VXI by the VXIplug&play Systems Alliance.
visual basic custom
a specific form of binary packaged object that can be created by
