Introduction to STEP 5 S5-100U
Block Structure
Each block consists of the following parts:
• The block header that specifies the block type, number, and length
- Generated by the programmer when it transforms the block
• The block body that has the STEP 5 program or data
Figure 7-3. Structure of a Block Header
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Synchronization
pattern
Block type
Block number
Programmer ID
Library number
Block length
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Programming
Program your blocks as follows (does not apply to data blocks):
1. Specify the block type (e.g., PB).
2. Specify the block number (e.g., 27).
3. Enter the control program statements.
4. Terminate the block with the “BE” statement.
7-8
EWA 4NEB 812 6120-02
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