Programming With Symbolic Addresses - Siemens SIMATIC S7-GRAPH Manual

Programming Actions and Conditions
Transition Number (for example, T1) and Transition Name (for example, Trans1)
The transition name and transition number must be unique and can be adapted
later in all three programming language representations.
• The transition number is assigned automatically by the system (range: 1 to
999).
If the transition number of the first transition is assigned manually in a branch
path, when you insert further step-transition pairs, the numbers are assigned by
the system automatically starting at the number entered manually. This simply
leads to interrupted numbering of the step-transition pairs. You can renumber
the steps and transitions at any time so that individual areas are consecutively
numbered.
• The transition name is automatically assigned by the system (range: Trans1 to
Trans999). It can consist of a maximum of 24 alphanumeric characters. The
first character must be a letter. If the zoom factor is too low, the display of the
transition name is suppressed. You can modify the transition name in the
"Transition Properties" dialog box.
7.12

Programming with Symbolic Addresses

stepTo make the program and sequential control system clearer, you can use
addresses with symbolic identifiers or names instead of absolute addresses.
Symbolic addresses are assigned in the symbol table. You can add further
symbolic addresses to the symbol table that you define while creating the
sequencer with S7-Graph.
The symbol table is automatically created in the S7 program and can be displayed
using the menu command Options > Symbol Table or in the SIMATIC manager
using the "Symbols" folder.
A section of the symbol table with the symbols used in a step is displayed in
S7-Graph at the single step display level.
Requirements for Using Symbolic Addresses
Symbolic addresses can only be used when a symbolic name has been assigned
to the absolute addresses in the symbol table.
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S7-GRAPH for S7 300/400 Programming Sequential Control Systems
C79000-G7076-C526-01