STEP 5 Programming Language
2.1
STEP 5 Programming Language
Types of operation
2.1.1
The LAD, CSF, STL
Methods of Representation
Graphic representation or
list of statements
2 - 4
With the STEP 5 programming language, you convert automation
tasks into programs that run on SIMATIC S5 programmable
controllers. You can program simple binary functions, complex
digital functions and arithmetic operations including floating
point arithmetic using STEP 5.
The operations of the STEP 5 programming language are divided into
the following groups:
Basic operations
• • you can use these operations in all logic blocks
• • methods of representation: ladder diagram (LAD), control system
flowchart (CSF), statement list (STL).
Supplementary operations and system operations:
• • can only be used in function blocks
• • only statement list (STL) method of representation
• • system operations: only experienced STEP 5 programmers should
use system operations
When programming in STEP 5, you can choose between the three
methods of representation ladder diagram (LAD), control system
flowchart (CSF) and statement list (STL) for each individual logic block.
You can choose the method of representation that best suits your
particular application.
The machine code MC5 that the programmers (PGs) generate is the
same for all three methods of representation.
If you follow certain rules when programming in STEP 5 (see /3/), the
programmer can translate your user program from one method of
representation into any other.
While the ladder diagram (LAD) and control system flowchart (CSF)
methods of representation represent your STEP 5 program
graphically, statement list (STL) represents STEP 5 operations
individually as mnemonic abbreviations.
CPU 948 Programming Guide
C79000-G8576-C848-04