Campbell CR850, Руководство оператора

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Section 7. Installation
131
Consider the Average() instruction as an example of output processing
instructions. Average() stores the average of a variable over the final data storage
output interval. Its parameters are:
•
Reps
— number of elements in the variable array for which to calculate
averages. Reps is set to 1 to average PTemp, and set to 2 to average 2
thermocouple temperatures, both of which reside in the variable array
"Temp_C".
•
Source
— variable array to average. Variable arrays PTemp_C (an array of 1)
and Temp_C() (an array of 2) are used.
•
DataType
— Data type for the stored average (the example uses data type
FP2, which is the Campbell Scientific two-byte floating point data type).
Read More! See Data Types
(p. 118)
for more information on available data types.
•
DisableVar
— controls whether a measurement or value is included in an
output processing function. A measurement or value is not included if
DisableVar
is true ( ≠ 0). For example, if the disable variable in an Average()
instruction is true, the current value will not be included in the average.
CRBasic example Use of the Disable Variable
and CRBasic example Using
NAN to Filter Data
(p. 410)
show how
DisableVar
can be used to exclude values
from an averaging process. Whether DisableVar is True or False is controlled
by
Flag1
. When
Flag1
is high, or
True
,
DisableVar
is
True
. When it is
False
,
DisableVar
is
False
. When
False
is entered as the argument for
DisableVar
, all
readings are included in the average. The average of variable
Oscillator
does
not include samples occurring when Flag1 is high ( True ), which results in an
average of 2; when
Flag1
is low or
False
(all samples used), the average is
1.5
.
Read More! TrigVar and DisableVar (p. 223)— Controlling Data Output and
Output Processing
(p. 223)
and Measurements and NAN
(p. 408)
discuss the use of
TrigVar
and
DisableVar
in special applications.
Read More! For a complete list of output processing instructions, see section
Final Data Storage (Output) Processing
(p. 454).
Numbers of Records
The exact number of records that can be stored in a data table is governed by a
complex set of rules, the summary of which can be found in the appendix
Numbers of Records in Data Tables
.
7.7.3.5.2 Subroutines
Read More! See Subroutines
(p. 188)
for more information on programming with
subroutines.
Subroutines allow a section of code to be called by multiple processes in the main
body of a program. Subroutines are defined before the main program body of a
program.
Note A particular subroutine can be called by multiple program sequences
simultaneously. To preserve measurement and processing integrity, the CR800
queues calls on the subroutine, allowing only one call to be processed at a time in