Step 5 Operations; Basic Operations; Boolean Logic Operations - Siemens SIMATIC S5 Manual

S5-115F Manual
3

STEP 5 Operations

The STEP 5 programming language has the following three operation types:
• The basic operations include functions that can be executed in:
- Organization blocks
- Program blocks
- Sequence blocks
- Function blocks
Apart from a few exceptions, basic operations can be represented in CSF and LAD.
The exceptions are:
- Arithmetic operations
- Block operations
- Other operations
- The BLD 255 operation for segmenting the user program ( 3.1.10)
• Supplementary operations can only be used in FBs and contain complex functions such as
substitution statements, check functions, shift and conversion operations.
Supplementary operations can only be input and output in STL.
• System operations can only be used in FBs and they access the operating system direct. They
must only be used by an experienced programmer.
System operations can only be input and output in STL.
3.1

Basic Operations

Sections 3.1.1 through 3.1.9 describe the basic operations with examples.
3.1.1

Boolean Logic Operations

These operations implement sequential Boolean logic. The new RLO (result of the logic operation)
is generated from the previous RLO, internal information and the current operand status.
EWA 4NEB 811 6149-02
(OBs)
(PBs)
(SBs)
(FBs)
( 3.1.7)
( 3.1.8)
( 3.1.9)

STEP 5 Operations

3-1