PLC Programming

Declaration Editor...
Depending on the type and contents of pragma, the pragma either operates on the line in which it is
located or on all subsequent lines until it is ended by an appropriate pragma, or the same pragma is
executed with different parameters, or the end of the file is reached. By file we mean here: declaration
part, implementation portion, global variable list, type declaration.
The opening bracket may immediately follow a variable name. Opening and closing brackets must be
located on the same line.
The following pragma may currently be used:
{flag [] [off|on]}
can be a combination of the following flags:
noinit:
nowatch:
noread:
nowrite:
The variable will not be initialized.
The variable can not be monitored
The variable is exported to the symbol file without read permission
The variable is exported to the symbol file without write permission
noread,
nowrite:
The variable will not get exported to the symbol file
With the „on" modifier, the pragma operates on all subsequent variable declarations until it is ended
by the pragma {flag off}, or until overwritten by another {flag on} pragma.
Without the „on" or „off" modifier, the pragma operates only on the current variable declaration (that is
the declaration that is closed by the next semicolon).
Examples:
The variable a will not be initialized and will not be monitored. The variable b will not be initialized:
VAR
a : INT {flag noinit, nowatch};
b : INT {flag noinit };
END_VAR
VAR
{flag noinit, nowatch on}
a : INT;
{flag noinit on}
b : INT;
{flag off}
END_VAR
Neither variable will be initialized:
{flag noinit on}
VAR
a : INT;
b : INT;
END_VAR
{flag off}
VAR
{flag noinit on}
a : INT;
b : INT;
{flag off}
END_VAR
The flags „noread" and „nowrite" are used, in a POU that has read and/or write permission, to
provide selected variables with restricted access rights. The default for the variable is the same as the
setting for the POU in which the variable is declared. If a variable has neither read nor write
permission, it will not be exported into the symbol file.
Examples:
5-10 CoDeSys V2.3