National Instruments NI USB-621x User Manual

Page 164

Glossary

G-15

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.

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.

Seconds.

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.