Campbell CR5000, Руководство оператора

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Section 9. Program Control Instructions
9-14
Parameter
& Data Type Enter
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
Option
Constant The Option parameter determines how data will be buffered during the
Scan…NextScan process. The options are:
Option Result
0, 1, or 2 The datalogger uses two buffers when processing
measurements. When a measurement begins on a scan,
the values of the previous scan are loaded into a buffer.
This allows processing to finish on the previous scan
during measurement of the current scan.
>3 The datalogger uses three or more buffers when
processing measurements, based on the number of scans
defined by this Constant.
Larger buffers can be used for a Scan that has occasional large processing
requirements such as FFTs or Histograms, and/or when processing may be
interrupted by communications. If a value of 1000 is inserted into the
BufferSize argument of a scan having 10 thermocouple measurements,
40,000 bytes of SRAM will be allocated for the buffer [(4 bytes) /
(measurement) x (10 measurements)/(buffered scan) x 1000 buffered
scans)]. The buffer size plus the size of any Output Tables stored in SRAM
should not exceed 2 megabytes.
If the processing ever lags behind by more than the buffer allocated, the
datalogger will discard the buffered values and synchronize back up to the
current measurement
The SlowSequence instruction does not allow for this buffering scheme even
though Scan is used to signify the start of a scan in a slow sequence. In
SlowSequence, the measurements are stored in a single buffer. Processing of
this buffer is completed before the NextScan measurements are made.
Count
Integer The number of times to execute the Scan/NextScan loop. Enter 0 for infinite
looping.