Technical data

Programming with STEP 7
Manual, 05/2010, A5E02789666-01 11
Contents
1 Introducing the Product and Installing the Software.............................................................................23
1.1 Overview of STEP 7................................................................................................................23
1.2 The STEP 7 Standard Package..............................................................................................28
1.3 What's New in STEP 7, Version 5.5? .....................................................................................33
1.4 Extended Uses of the STEP 7 Standard Package .................................................................35
1.4.1
Engineering Tools...................................................................................................................37
1.4.2 Run-Time Software.................................................................................................................39
1.4.3 Human Machine Interface.......................................................................................................41
2 Installation..................................................................................................................................................43
2.1 Automation License Manager.................................................................................................43
2.1.1 User Rights Through The Automation License Manager .......................................................43
2.1.2 Installing the Automation License Manager............................................................................46
2.1.3 Guidelines for Handling License Keys....................................................................................47
2.2 Installing STEP 7 ....................................................................................................................48
2.2.1 Installation Procedure .............................................................................................................50
2.2.2 Setting the PG/PC Interface ...................................................................................................53
2.3 Uninstalling STEP 7................................................................................................................55
2.4 User Rights .............................................................................................................................55
2.4.1
User Rights in MS Windows XP/Server 2003.........................................................................55
2.4.2 User Rights in MS Windows 7 ................................................................................................56
3 Working Out the Automation Concept....................................................................................................59
3.1 Basic Procedure for Planning an Automation Project.............................................................59
3.2 Dividing the Process into Tasks and Areas............................................................................60
3.3 Describing the Individual Functional Areas ............................................................................62
3.4 Listing Inputs, Outputs, and In/Outs .......................................................................................64
3.5 Creating an I/O Diagram for the Motors..................................................................................65
3.6 Creating an I/O Diagram for the Valves..................................................................................66
3.7 Establishing the Safety Requirements....................................................................................67
3.8 Describing the Required Operator Displays and Controls......................................................68
3.9 Creating a Configuration Diagram ..........................................................................................69
4
Basics of Designing a Program Structure..............................................................................................71
4.1 Programs in a CPU.................................................................................................................71
4.2 Blocks in the User Program ....................................................................................................72
4.2.1
Organization Blocks and Program Structure ..........................................................................73
4.2.2 Call Hierarchy in the User Program........................................................................................80
4.2.3 Block Types ............................................................................................................................82
4.2.3.1 Organization Block for Cyclic Program Processing (OB1) .....................................................82
4.2.3.2 Functions (FC) ........................................................................................................................88
4.2.3.3 Function Blocks (FB)...............................................................................................................90
4.2.3.4 Instance Data Blocks ..............................................................................................................93
4.2.3.5 Shared Data Blocks (DB)........................................................................................................96
4.2.3.6 System Function Blocks (SFB) and System Functions (SFC) ...............................................97