Overview of the block types - STEP 7

Programming basics

ft:publication_title
Programming basics
Product
STEP 7
Version
V20
Publication date
11/2024
Language
en-US
Overview of the block types

Block types

Different BLOCK types are available to perform tasks within an automation system. The following table shows the available block types:

Block type

Brief description

Organization blocks  (OB)

Organization blocks define the structure of the user program.

Functions  (FC)

Functions contain program routines for recurring tasks. They have no "memory".

Function blocks  (FB)

Function blocks are code blocks that store their values permanently in instance data blocks, so that they remain available even after the block has been executed.

Instance data blocks 

Instance data blocks are assigned to a function block when it is is called for the purpose of storing program data.

Global data blocks 

Global data blocks are data areas for storing data that can be used by any blocks.