2 Introduction to STEP 5
2.1 Writing a Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1
2.1.1 Methods of Representation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 1
2.1.2 Operand Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 3
2.1.3 Circuit Diagram Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 4
2.2 Program Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 4
2.2.1 Linear Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 4
2.2.2 Structured Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 5
2.3 Block Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 6
2.3.1 Organization Blocks (OBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 7
2.3.2 Program Blocks (PBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 13
2.3.3 Sequence Blocks (SBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 13
2.3.4 Function Blocks (FBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 14
2.3.5 Data Blocks (DBs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 18
2.4 Modifying the Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 20
2.5 Number Representation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 - 20
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