National Instruments 653X User Manual
Page 134
Glossary
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sample rate
the number of samples a system takes over a given time period, usually
expressed in samples per second
software trigger
a programmed event that triggers an event such as data acquisition
STOPTRIG
Strobed I/O
Any operation where every data transfer is timed by hardware signals. In
the case of pattern I/O, this hardware signal is a clock edge. In the case of
handshaking I/O, hardware signals involve two or three handshaking lines.
synchronous
For hardware, it is a property of an event that is synchronized to a reference
clock. For software, it is a property of a function that begins an operation
and returns only when the operation is complete.
T
transfer rate
the rate, measured in bytes/s, at which data is moved from source to
destination after software initialization and set up operations; the maximum
rate at which the hardware can operate
trigger
any event that causes or starts some form of data capture
TTL
Transistor-Transistor Logic
U
unstrobed I/O
Basic digital I/O operations that do not involve the use of control signals in
data transfers. Unstrobed data transfers are controlled by software
commands. Also known as software-timed I/O.
V
V
Volts
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
virtual channels
channel names that can be defined outside the application and used without
having to perform scaling operations