CR1000 Manual - Campbell Scientific

Section 7. Installation
Table 9. CRBasic Program Structure
Declarations
Declare constants
Declare Public variables
Dimension variables
Define Aliases
Define Units
Define data tables.
Process / store trigger
Table size
Other on-line storage devices
Processing of data
Begin program
Set scan interval
Measurements
Processing
Call data table(s)
Initiate controls
NextScan
End program
Define CR1000 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 CR1000
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.
Send data to a CF card (CRD: drive) or Campbell
Scientific mass-storage media (USB: drive) if
available.
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 CR1000 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 CR1000 actions.
CRBasic Example 6.
Proper Program Structure
'Declarations
'Define Constants
Const RevDiff = 1
Const Del = 0 'default
Const Integ = 250
Const Mult = 1
Const Offset = 0
Declare constants
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