Glossary

single-ended output

A circuit whose output signal is present between one output terminal and

 

ground.

software applications

The programs that run on your computer and perform a specific user-

 

oriented function, such as accounting, program development,

 

measurement, or data acquisition. In contrast, operating system functions

 

basically perform the generic "housekeeping" of the machine, which is

 

independent of any specific application. Operating system functions

 

include the saving of data (file system), handling of multiple programs at

 

the same time (multi-tasking), network interconnection, printing, and

 

keyboard/user interface interaction.

software triggering

A method of triggering in which you simulate an analog trigger using

 

software. Also called conditional retrieval.

source impedance

A parameter of signal sources that reflects current-driving ability of voltage

 

sources (lower is better) and the voltage-driving ability of current sources

 

(higher is better).

synchronous

1. Hardware—A property of an event that is synchronized to a reference

 

clock.

 

2. Software—A property of a function that begins an operation and

 

returns only when the operation is complete. A synchronous process is,

 

therefore, locked and no other processes can run during this time.

T

 

task

In NI-DAQmx, a collection of one or more channels, timing, and triggering

 

and other properties that apply to the task itself. Conceptually, a task

 

represents a measurement or generation you want to perform.

TC

See terminal count.

terminal

An object or region on a node through which data passes.

terminal count

The highest value of a counter.

tgh

Gate hold time.

tgsu

Gate setup time.

tgw

Gate pulse width.

© National Instruments Corporation

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NI USB-621x User Manual