Glossary

Q

quadrature encoder

An encoding technique for a rotating device where two tracks of

 

information are placed on the device, with the signals on the tracks offset

 

by 90° from each other. This makes it possible to detect the direction of the

 

motion.

R

range

The maximum and minimum parameters between which a sensor,

 

instrument, or device operates with a specified set of characteristics. This

 

may be a voltage range or a frequency range.

real time

1. Displays as it comes in; no delays.

 

2. A property of an event or system in which data is processed and acted

 

upon as it is acquired instead of being accumulated and processed at a

 

later time.

 

3. Pertaining to the performance of a computation during the actual time

 

that the related physical process transpires so results of the

 

computation can be used in guiding the physical process.

RSE

Referenced Single-Ended configuration—All measurements are made with

 

respect to a common reference measurement system or a ground. Also

 

called a grounded measurement system.

RTSI

Real-Time System Integration.

RTSI bus

Real-Time System Integration bus—The National Instruments timing bus

 

that connects DAQ devices directly, by means of connectors on top of the

 

devices, for precise synchronization of functions.

S

s

Seconds.

S

Samples.

sample counter

The clock that counts the output of the channel clock, in other words, the

 

number of samples taken. On devices with simultaneous sampling, this

 

counter counts the output of the scan clock and hence the number of scans.

© National Instruments Corporation

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NI USB-621x User Manual