Technical data

Displaying Reference Data
14.1 Overview of the Available Reference Data
Programming with STEP 7
312 Manual, 05/2010, A5E02789666-01
14.1.2 Program Structure
The program structure describes the call hierarchy of the blocks within an S7 user program. You
are also given an overview of the blocks used, their dependencies, and their local data
requirements.
Using the menu command View > Filter in the "Generating Reference Data" window you open a
tabbed dialog box. In the "Program Structure" tab you can set how you want the program structure
displayed.
You can choose between:
• Call structure and
• Dependency structure
Symbols for the Program Structure
Symbol Meaning
Block called normally (CALL FB10)
Block called unconditionally (UC FB10)
Block called conditionally (CC FB10)
Data block
Recursion
Recursion and called conditionally
Recursion and called unconditionally
Block not called
• Recursions in the call are recognized and indicated graphically in the call structure.
• Recursions within the call hierarchy are indicated by different symbols.
• Regularly called blocks (CALL), conditionally called blocks (CC) or unconditionally called
blocks (UC) are marked by different symbols.
• Blocks not called are displayed at the bottom of the call structure and marked with a black
cross. There is no further breakdown of the call structure of a block which is not called.