National Instruments 653X Manuale Utente

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

see 

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.

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

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

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