Campbell Scientific CR9000X Measurement and Control System - Manual (Page 354)

Section 9. Program Control Instructions
Only one Super Subscan can exist in each main Scan structure. NOTE
MEASUREMENT LOOP SUBSCAN: This SubScan is similar to a simple
For/Next loop. To run at the fastest rate, enter zero for the SubScan interval.
If it is desired to run through the SubScan at a specific interval, then the
interval can be entered. The last parameter (SubRatio) of the SubScan
instruction specifies how many times to loop through the SubScan each time it
is encountered.
Similar to the CR9052 SubScan, the number of SubScans that will be
buffered for the Measurement Loop SubScan is the product of the SubRatio
parameter and the main Scan's Buffer parameter.
THE FOLLOWING INSTRUCTIONS CANNOT BE USED IN
A SUBSCAN: NOTE
AM25T, PortSet, PortGet, PulseCount, PulseCountReset,
ReadIO, SDMAO4, SDMCAN, SDMCD16AC, SDMCVO4,
SDMINT8, SDMIO16AC, SDMSpeed, SDMSW8A, SubScan,
TimerIO, WaitDigTrig, WriteIO
Parameter Enter SUBSCAN PARAMETERS
SubInterval
Constant
The time interval at which to run the SubScan.
For the Filter SubScan, this interval must be one of the valid intervals for the CR9052
module, and, the interval of the scan that contains the SubScan must be an integer multiple of
the SubScan interval.
Enter 0 for the Super (Isolation) SubScan.
For the measurement Loop Subscan, enter 0 for fastest measurements or, enter a time value if
it is desired to loop through the SubScan at a specified interval.
Units The units for the Interval. Enter 0 when using a Super (Isolation) SubScan. Enter 0 for the
Loop SubScan to run at the fastest rate.
Constant Alpha
Code Numeric
Code
Units
USEC 0 Microseconds
MSEC
SEC 1
2 Milliseconds
Seconds
SubRatio
Constant
The Subscan will run SubRatio times each time the main scan runs.
For the Filter SubScan this parameter must be the integer ratio of the main Scan Interval to
the SubScan Interval.
For the Isolation SubScan, this parameter must be a negative number and represents the ratio
of the SubScan interval to the main Scan interval. This type of Subscan runs at a slower rate
than the main Scan and will have an interval that is an integer multiple of the main Scan
interval.
For the measurement Loop SubScan, this parameter specifies how many times to loop
through the Subscan each time it is encountered.
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