Campbell CR6 Series, Руководство оператора

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Section 11. Glossary
585
Term: full-duplex
A serial communication protocol. Simultaneous bi-directional
communications. Communications between a CR6 serial port and a PC is
typically full duplex.
Reading list: simplex
(p. 601),
duplex
(p. 359),
half duplex
(p. 586),
and full duplex
(p.
585).
Term: frequency domain
Frequency domain describes data graphed on an X-Y plot with frequency as
the X axis. VSPECT
(p. 608)
vibrating wire data are in the frequency domain.
Term: frequency response
Sample rate is how often an instrument reports a result at its output;
frequency response is how well an instrument responds to fast fluctuations on
its input. By way of example, sampling a large gage thermocouple at 1 kHz
will give a high sample rate but does not ensure the measurement has a high
frequency response. A fine-wire thermocouple, which changes output quickly
with changes in temperature, is more likely to have a high frequency
response.
Term: garbage
The refuse of the data communication world. When data are sent or received
incorrectly (there are numerous reasons why this happens), a string of invalid,
meaningless characters (garbage) often results. Two common causes are: 1) a
baud-rate mismatch and 2) synchronous data being sent to an asynchronous
device and vice versa.
Term: global variable
A variable available for use throughout a CRBasic program. The term is
usually used in connection with subroutines, differentiating global variables
(those declared using
Public
or
Dim
) from local variables, which are
declared in the Sub() and Function() instructions.
Term: ground
Being or related to an electrical potential of 0 volts.
Term: ground currents
Pulling power from the CR6 wiring panel, as is done when using some
comms devices from other manufacturers, or a sensor that requires a lot of
power, can cause voltage potential differences between points in CR6