→Function block

according to →IEC-standard: programmable organization unit (POU) which represents for the purpose of modularization and structuring a well-defined portion of the →program; The function block concept is realized by the →function block type and the →function block instance.

A function block is a →program organization unit (such as a →program and a →function ) which store its states.
 Function blocks can be declared using the following elements:

  • →data types (elementary data types and user-defined data types)

  • functions (system functions and user-defined functions)

  • system function blocks (such as Bistable function blocks)

  • previously declared function blocks

logi.CAD 3 supports declaration/usage of function blocks in these languages (according to IEC-standard):

language

details under

→ST, incl. →SFC

"Declaration of a function block in ST", "Call of function block instance in ST", "SFC elements in ST"

→FBD, incl. →SFC

"Creating POU in FBD", "Calls of blocks: functions or function blocks", "FBD-elements in drawing field", "SFC elements in drawing field "

→LD

" Creating POU in LD " and " Functions and function blocks in LD "

Moreover, it is possible to create function blocks in →C or →C++ and to use them in ST. See "Integrating C-code and/or C++-code into the application (deprecated)".