CR200/CR200X Series Dataloggers - Campbell Scientific

Section 9. Programming
9.5 Structure
TABLE. CRBASIC Program Structure (p. 72) delineates CRBASIC program
structure:
Table 6. CRBASIC Program Structure
Declarations
Declare constants
Declare Public variables
Dimension variables
Define Aliases
Define Units
Define data tables.
Process/store trigger
Table size
Processing of Data
Begin Program
Set scan interval
Measurements
Processing
Call Data Table(s)
Initiate controls
NextScan
End Program
Define datalogger memory usage. Declare constants,
variables, aliases, units, and data tables.
List fixed constants
List / dimension variables viewable during program
execution
List / dimension variables not viewable during program
execution.
Assign aliases to variables.
Assign engineering units to variable (optional). Units
are strictly for documentation. The CR200(X) makes no
use of Units nor checks Unit accuracy.
Define stored data tables
Set triggers when data should be stored. Triggers may
be a fixed interval, a condition, or both.
Set the size of a data table
List data to be stored in the data table, e.g. samples,
averages, maxima, minima, etc.
Processes or calculations repeated during program
execution can be packaged in a subroutine and called
when needed rather than repeating the code each time.
Begin Program defines the beginning of statements
defining datalogger actions.
The scan sets the interval for a series of measurements
Enter measurements to make
Enter any additional processing
Declared data tables must be called to process and
store data
Check measurements and initiate controls if necessary
Loop back to Set Scan and wait for the next scan
End Program defines the ending of statements defining
datalogger actions.
CRBASIC EXAMPLE. Proper Program Structure (p. 73) demonstrates the
proper structure of a CRBASIC program.
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