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Crbasic example 9. use of the disable variable – Campbell Scientific CR200/CR200X-series Dataloggers User Manual

Page 94

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Section 9. Programming

Consider the Average () instruction as an example of output processing

instructions. Average () stores the average of a variable over the 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 Batt_Volt, and set to 2 to average 2

thermistor temperatures, both of which reside in the variable array

"T109_C".

Source-variable array to average. Variable arrays Batt_Volt (an array of 1)

and T109_C() (an array of 2) are used.

DisableVar-controls whether or not a measurement or value is included in

an output processing function. A measurement or value will not be included

if the disable variable is true (≠ 0). For example, in the case of an Average

() output processing instruction, if, on a particular pass through the data

table, the Average () disable variable true, the value resident in the variable

to be averaged with not be included in the average. Program CRBASIC

EXAMPLE. Use of the Disable Variable has "False" entered for the disable

variable, so all readings are included in the averages; the average of

variable "Oscillator" does not include samples occurring when Flag 1 is

high, producing an average of 2, whereas, when Flag 1 is low (all samples

used), an average of 1.5 is calculated.

Read More!

TrigVar and DisableVar - Controlling Data

Output and Output Processing

(p. 125) discusses the

use of TrigVar and DisableVar in special applications.

CRBASIC EXAMPLE 9.

Use of the Disable Variable

'Declare Variables and Units

Public Oscillator

Public Flag

Public DisableVar

'Define Data Tables

DataTable (OscAvgData,True,-1)

DataInterval (0,1,Min)

Average (1,Oscillator,DisableVar)

EndTable

'Main Program

BeginProg

Scan (1,Sec)

'Reset and Increment Counter

If Oscillator = 2 Then Oscillator = 0

Oscillator = Oscillator + 1

'Process and Control

If Oscillator = 1

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