Campbell Scientific CR9000X Measurement and Control System - Manual (Page 345)

Section 9. Program Control Instructions
Scan
The Scan instruction is used to establish the program scan rate, scan count, and
size of the scan buffer. The NextScan instruction shifts program control to the
Scan instruction.
Syntax
Scan(Interval, Units, Option, Count)
...
...[ExitScan] or ...[ContinueScan]
...
Next Scan
Remarks
The measurements, processing, and calls to output tables bracketed by the
Scan…NextScan instructions determine the sequence and timing of the
datalogger program. The Scan instruction determines how frequently the
measurements within the Scan…NextScan structure are made, controls the
buffering capabilities, and sets the number of times to loop through the scan.
When using the CR9052 with scan rates over 1000 Hz, it is
recommended to use SubScans and large scan buffers. See the
SubScan topic in Section 9.1 Program Structure/Control for
more details. TIP
Slow Sequence Scans only support a Buffer option of 1. NOTE
ExitScan is used to setup a condition where the Scan loop will be exited.
ContinueScan is used to jump to the end of the Scan loop without processing
the processing instructions between the ContinueScan and the Next Scan. It
does not affect the measurement instructions.
Parameter
& Data Type Enter SCAN PARAMETERS
Interval
Constant Enter the time interval at which the scan is to be executed. The interval may
be in µs, ms, s, or minutes, whichever is selected with the Units parameter.
The maximum scan interval is one minute.
Units The units for the time parameters.
Constant Alpha
Code Numeric
Code
Units
USEC 0 microseconds
MSEC 1 milliseconds
SEC 2 seconds
MIN 3 minutes
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