User Manual

Programming made easy

6.1 Easy to design your user program

Easy Book

88 Manual, 03/2014, A5E02486774-AF

Calling block (or interrupted block)

Called FB or BC (or interrupting OB)

①

Program execution

②

Instruction (or interrupting event) that initiates

the execution of another block

③

Program execution

④

Block end (returns to calling block)

You can nest the block calls for a more modular structure. In the following example, the

nesting depth is 3: the program cycle OB plus 3 layers of calls to code blocks.

①

Start of cycle

②

Nesting depth

By creating generic code blocks that can be reused within the user program, you can simplify

the design and implementation of the user program.

● You can create reusable blocks of code for standard tasks, such as for controlling a pump

or a motor. You can also store these generic code blocks in a library that can be used by

different applications or solutions.

● When you structure the user program into modular components that relate to functional

tasks, the design of your program can be easier to understand and to manage. The

modular components not only help to standardize the program design but can also help

to make updating or modifying the program code quicker and easier.

● Creating modular components simplifies the debugging of your program. By structuring

the complete program as a set of modular program segments, you can test the

functionality of each code block as it is developed.

● Utilizing a modular design that relates to specific functional tasks can reduce the time

required for the commissioning of the completed application.