“Exclude from build”

: This object and recursively its child objects are not considered for the next compile process.

The object entry is displayed in green fonts in the “Devices” or “POUs” view.

“External implementation”

“(Late link in the runtime system) ”

: CODESYS does not generate any code for this object when compiling the project. The object is linked as soon as the project is running on the target system, provided it is available there (for example, in a library).

The object name is postfixed with ‎(EXT)‎ in “Devices” or “POUs” view.

“Enable system call”

: A system call (runtime system) for functions is possible.

Background: As opposed to CoDeSys V2.3, the ADR operator in V3 can be used with function names, program names, function block names, and method names. It replaces the INSTANCE_OF operator.

BUT: It is not possible to call function pointers from within CODESYS.

“Link always”

: The object is marked by the compiler and therefore always included in the compile information. This means that it is always compiled and downloaded to the PLC.

Note: The pragma ‎{attribute 'linkalways'}‎ can also be used to instruct the compiler to always include an object.

“Compiler defines”

Here you can specify defines or conditions for compiling the object (conditional compile). You can also type in the expression ‎expr‎, which is used in these kinds of pragmas. Multiple entries are possible as a comma-separated list (see ‎{define}‎ statements).

Example: ‎hello, test:='1'‎

“Additional compiler definitions from the device description”

“Defined in device”

List of compiler definitions that originate from the device description. These compiler definitions are used in the build if they are not listed in the “Ignored definitions” field.

“Ignored definitions”

List of compiler definitions from the device description that are not used in the build.

Copies the selected compiler definition from the “Defined in device” field to the “Ignored definitions” field.

Moves the selected compiler definition from the “Ignored definitions” field to the “Defined in device” field. The compiler definition is used in the build.