Campbell CR300 series, Руководство оператора

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B-1
Appendix B. Introduction to CRBasic
Programming
Essential elements of a CRBasic program are listed in TABLE B-1 , and
demonstrated in CRBasic Example B-1 .
TABLE B-1. CRBasic Program Structure
D
ecl
ar
at
io
ns
Declare constants List fixed constants using Const .
Declare Public variables
List, and if necessary, dimension
variables viewable during program
execution.
Declare Dim variables
List, and if necessary, dimension
variables not viewable during program
execution.
Define aliases Assign aliases to variables using Alias .
Define units
Assign engineering units to variable
(optional).
Units
are strictly for
documentation. The CR300 makes no use
of Units nor checks Unit accuracy.
Define data tables
DataTable() defines stored data tables.
The CR300 can save up to 20 data tables.
Processing of data
List data to be stored in the data table, for
example, Sample() , Average() ,
Maximum() , Minimum() .
Begin program
BeginProg defines the beginning of
statements defining CR300 actions.
Sc
an L
oop
Begin scan
Scan sets the interval for a series of
measurements.
Measurements Enter measurements to make.
Processing of data Enter any additional processing.
Call data table(s)
Declared data tables must be called using
CallTable to process and store data.
Initiate controls
Check measurements and initiate controls
if necessary.
Next scan
NextSca n loops back to the beginning of
the scan and waits for the next scan.
End program
EndProg defines the end of statements
defining CR300 actions.