Campbell CR1000, Руководство оператора

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Section 11. Glossary
Term. watchdog timer
An error-checking system that examines the processor state, software timers,
and program-related counters when the CRBasic program is running. See
section Watchdog Errors
(p. 488).
The following will cause watchdog timer
resets, which reset the processor and CRBasic program execution.
o Processor bombed
o
Processor neglecting standard system updates
o Counters are outside the limits
o Voltage surges
o Voltage transients
When a reset occurs, a counter is incremented in the WatchdogTimer entry
of the
Status
table
(p. 603).
A low number (1 to 10) of watchdog timer resets is
of concern, but normally indicates that the situation should just be monitored.
A large number of errors (>10) accumulating over a short period indicates a
hardware or software problem. Consult with a Campbell Scientific
application engineer.
Term. weather-tight
Describes an instrumentation enclosure impenetrable by common
environmental conditions. During extraordinary weather events, however,
seals on the enclosure may be breached.
Term. web API
Application Programming Interface (see the section Web Service API
(p. 423),
for more information).
Term. wild card
a character or expression that substitutes for any other character or
expression.
Term. XML
Extensible markup language.
Term. user program
The CRBasic program written by you in Short Cut program wizard or
CRBasic Editor .
11.2 Concepts
11.2.1 Accuracy, Precision, and Resolution
Three terms often confused are accuracy, precision, and resolution. Accuracy is a
measure of the correctness of a single measurement, or the group of
measurements in the aggregate. Precision is a measure of the repeatability of a
group of measurements. Resolution is a measure of the fineness of a
measurement. Together, the three define how well a data-acquisition system
performs. To understand how the three relate to each other, consider "target
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