Campbell CR800 Series, Operator'S Manual

Page: 126 / 598

Section 7. Installation
126
•
Alias
•
StationName
The table
Rules for Names
(p. 159)
lists declaration names and allowed lengths.
See Predefined Constants
(p. 138)
for other naming limitations.
7.6.3.3 Declaring Variables
A variable is a packet of memory that is given an alphanumeric name.
Measurements and processing results pass through variables during program
execution. Variables are declared as
Public
or
Dim
.
Public
variables are
viewable through numeric monitors
(p. 506).
Dim variables cannot be viewed. A
public variables can be set as read-only, using the ReadOnly instruction, so that it
cannot be changed from a numeric monitor. The program, however, continues to
have read/write access to the variable.
Declared variables are initialized once when the program starts. Additionally,
variables that are used in the Function() or Sub() declaration, or that are declared
within the body of the function or subroutine, are local to that function or
subroutine.
Variable names can be up to 39 characters in length, but most variables should be
no more than 35 characters long. This allows for four additional characters that
are added as a suffix to the variable name when it is output to a data table.
Variable names can contain the following characters:
• A to Z
•
a to z
•
0 to 9
• _ (underscore)
•
$
Names must start with a letter, underscore, or dollar sign. Spaces and quote
marks are not allowed. Variable names are not case sensitive.
Several variables can be declared on a single line, separated by commas:
Public RefTemp, AirTemp2, Batt_Volt
Variables can also be assigned initial values in the declaration. Following is an
example of declaring a variable and assigning it an initial value.
Public SetTemp = {35}
In string variables, string size defaults to 24 characters (changed from 16
characters in April 2013, OS 26).