A function block is a POU which provides one or more values during the procedure.

As opposed to a function, a function block provides no return value⮫ “Function”.

A function block declaration begins with the keyword FUNCTION_BLOCK. Regard the recommendations on the naming⮫ “Recommendations on the naming of identifiers”.

Reproductions or instances (copies) of a function block can be created⮫ “Function block instances”.

The call of a function block is done via a function block instance⮫ “Calling a function block”.