Campbell CR6 Series, Руководство оператора

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Section 7. Installation
197
subroutines and functions. This feature allows creation of a CRBasic library of
reusable subroutines and functions that will not cause variable name conflicts. If
a program with local Dim variables attempts to use them globally, the compile
error undeclared variable will occur.
To make a local variable displayable, in cases where making it public creates a
naming conflict, sample the local variable to a data table and display the data
element table in a numeric monitor
(p. 592).
When exchanging the contents of a global and local variables, declare each
passing / receiving pair with identical data types and string lengths.
7.6.3.7 Initializing Variables
By default, variables are set equal to zero at the time the datalogger program
compiles. Variables can be initialized to non-zero values in the declaration.
Examples of syntax are shown in CRBasic example Initializing Variables
(p. 197).
Initializing Variables
'This program example demonstrates how variables can be declared as specific data types.
'Variables not declared as a specific data type default to data type Float. Also
'demonstrated is the loading of values into variables that are being declared.
Public aaa As Long = 1 'Declaring a single variable As Long and loading the value of 1.
Public bbb(2) As String *20 = {"String_1", "String_2"} 'Declaring an array As String and
'loading strings in each element.
Public ccc As Boolean = True 'Declaring a variable As Boolean and loading the value of True.
'Initialize variable ddd elements 1,1 1,2 1,3 & 2,1.
'Elements (2,2) and (2,3) default to zero.
Dim ddd(2,3)= {1.1, 1.2, 1.3, 2.1}
'Initialize variable eee
Dim eee = 1.5
BeginProg
EndProg
7.6.3.8 Declaring Constants
Declare a constant name at the beginning of a program to use the alphanumeric
name in place of a numeric or string value. In the body of the program, use the
name rather than the value itself to make the program more secure against
unintended changes, and easier to read and modify. CRBasic example
Using the
Const Declaration
(p. 198)
shows how to declare and use constants.
If declared using ConstTable / EndConstTable instructions, constants can be
changed on the CR1000KD Keyboard/Display while the program is running
( Configure , Settings | Constant Table ). Changes can also be made with the C
command in a terminal emulator (see
Troubleshooting – Using Terminal Mode
(p.
567))
.