Campbell Scientific CR6 CR6 Measurement and Control System - Page 134

One Statement on Multiple Lines, 8.3.4.1 Variables

Page 134 highlights

Section 7. Installation If A then B (implied EndIf) : C : D Rather, it does mean: If A then B : C : D (implied EndIf) 7.8.3.3.2 One Statement on Multiple Lines Long statements that overrun the CRBasic Editor page width can be continued on the next line if the statement break includes a space and an underscore ( _). The underscore must be the last character in a text line, other than additional white space. Note CRBasic statements are limited to 512 characters, whether or not a line continuation is used. Examples: Public A, B, _ C,D, E, F If (A And B) _ Or (C And D) _ Or (E And F) then ExitScan 7.8.3.4 Single-Line Declarations Public and Dim variables are declared at the beginning of a CRBasic program, as are Constants, Units, Aliases, StationNames, DataTables, and Subroutines. The table Rules for Names (p. 160) lists declaration names and allowed lengths. See the section Predefined Constants (p. 143) for another naming limitation. 7.8.3.4.1 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 either as Public or Dim at the discretion of the programmer. Public variables can be viewed through the external keyboard display or software numeric monitors. Dim variables cannot. Public variables can be set as read-only using the ReadOnly instruction, so that the variable cannot be changed from a display device. The program, however, continues to have read/write access to the variable. All user defined 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) 134

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Section 7.
Installation
If
A
then
B (implied
EndIf
) : C : D
Rather, it does mean:
If
A
then
B
:
C
:
D (implied
EndIf
)
7.8.3.3.2 One Statement on Multiple Lines
Long statements that overrun the
CRBasic Editor
page width can be continued on
the next line if the statement break includes a space and an underscore (
_
).
The
underscore must be the last character in a text line, other than additional white
space.
Note
CRBasic statements are limited to 512 characters, whether or not a line
continuation is used.
Examples:
Public
A, B, _
C,D, E, F
If
(A
And
B) _
Or
(C
And
D) _
Or
(E
And
F)
then ExitScan
7.8.3.4 Single-Line Declarations
Public
and
Dim
variables are declared at the beginning of a CRBasic program, as
are
Constant
s,
Units
,
Alias
es,
StationName
s,
DataTable
s, and
Subroutine
s.
The table
Rules for Names
(p. 160)
lists declaration names and allowed lengths.
See
the section
Predefined Constants
(p. 143)
for another naming limitation.
7.8.3.4.1 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 either as
Public
or
Dim
at the discretion of the
programmer.
Public
variables can be viewed through the external keyboard
display or software numeric monitors.
Dim
variables cannot.
Public variables can
be set as read-only using the
ReadOnly
instruction, so that the variable cannot be
changed from a display device.
The program, however, continues to have
read/write access to the variable.
All user defined 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)
134