Variable: VAR_CONFIG Permalink

Configuration variables assign the full address to variables which are declared in function blocks with incomplete address information and that should be mapped to device I/Os.

The declaration is made in a global variable list between the ‎VAR_CONFIG‎ and ‎END_VAR‎ keywords with the full instance path and with the correct address. This kind of global variable list is called a "variable configuration".

Example

Declaration of the ‎xLocIn‎ variable with an incomplete ‎%I*‎ address in a function block.

FUNCTION_BLOCK locio

VAR
        xLocIn AT %I* : BOOL := TRUE;
END_VAR

The ‎locio‎ function block is used in the ‎PLC_PRG‎ program.

PROGRAM PLC_PRG

VAR
        locioVar1 : locio;
END_VAR

The correct variables configuration in the global variable list is as follows:

VAR_CONFIG
        PLC_PRG.locioVar1.xLocIn AT %IX1.0 : BOOL;
END_VAR