Campbell Scientific CR1000 Measurement and Control System - Manual (Page 131)

Section 7. Installation
131
Data Output-Processing Instructions
Final data storage processing instructions (aka "output processing" instructions)
determine what data are stored in a data table. When a data table is called in the
CRBasic program, final data storage processing instructions process variables
holding current inputs or calculations. If trigger conditions are true, for example if
the output interval has expired, processed values are stored, or output, into the
data table. In CRBasic example Definition and Use of a Data Table
(p. 127),
three
averages are stored.
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. 431)
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. 222)— Controlling Data Output and
Output Processing
(p. 222)
and Measurements and NAN
(p. 428)
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. 477).
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
(p. 414).