7
Introduction to STEP 5
7.1
Writing a Program
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 1
7.1.1
Methods of Representation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 1
7.1.2
Operand Areas
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 3
7.1.3
Circuit Diagram Conversion
. . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 3
7.2
Programm Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 4
7.2.1
Linear Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 4
7.2.2
Structured Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 5
7.3
Block Types
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 7
7.3.1
Organization Blocks (OBs)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 9
7.3.2
Program Blocks (PBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 11
7.3.3
Sequence Blocks (SBs)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 11
7.3.4
Function Blocks (FBs)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 11
7.3.5
Data Blocks (DBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 16
7.4
Program Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 18
7.4.1
START-UP Program Processing
. . . . . . . . . . . . . . . . . . . . . . . . .
7 - 19
7.4.2
Cyclical Program Processing
. . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 21
7.4.3
Maximum Response Time with Cyclical Program Processing
. . . . .
7 - 23
7.4.4
Time-Controlled Program Processing . . . . . . . . . . . . . . . . . . . . . .
7 - 25
7.4.5
Maximum Response Time with Time-Controlled Program
Processing
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 28
7.4.6
Interrupt-Driven Program Processing
. . . . . . . . . . . . . . . . . . . . . .
7 - 29
7.5
Processing Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 30
7.5.1
Changing Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 30
7.5.2
Changing Blocks
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 30
7.5.3
Compressing the Program Memory
. . . . . . . . . . . . . . . . . . . . . . .
7 - 30
7.6
Number Representation
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 - 31
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a a
EWA 4NEB 812 6210-02