codesys no external access to var_in_out parameter

In CODESYS, the var_in_out parameter is used for passing a variable by reference. By default, var_in_out parameters are not accessible from outside the function or method where they are defined. They can only be accessed and modified within the scope of the function or method itself.

If you want to access the var_in_out parameter from outside, you can use an additional variable and assign the value of the var_in_out parameter to it within the function or method. Then, you can access and modify this additional variable from outside.

Here's an example:

FUNCTION ExampleVarInOut VAR_INPUT_OUTPUT
    var_in_out: INT;
END_FUNCTION

VAR
    externalVar: INT;
END_VAR

externalVar := 0; // Initialize the external variable

ExampleVarInOut(var_in_out := externalVar); // Pass the external variable by reference

// Now, you can access and modify the external variable
externalVar := externalVar + 1;

In this example, the var_in_out parameter is accessed and modified indirectly through the external variable.