Technical data

Defining Symbols
8.5 Symbol Table for Shared Symbols
Programming with STEP 7
204 Manual, 05/2010, A5E02789666-01
8.5.3 Incomplete and Non-Unique Symbols in the Symbol Table
Incomplete Symbols
It is also possible to store incomplete symbols. You can, for example, enter only the symbol name
first and then add the corresponding address at a later date. This means you can interrupt your
work on the symbol table at any time, save the interim result, and complete your work another time.
Incomplete symbols are identified in the "Status" column by the
symbol. When you come to use
the symbol for creating software (without an error message appearing), you must have entered the
symbolic name, the address, and the data type.
How Ambiguous Symbols Occur
Ambiguous symbols occur when you insert a symbol in the symbol table whose symbolic name
and/or address was already used in another symbol row. This means both the new symbol and the
existing symbol are ambiguous. This status is indicated by the symbol
in the "Status" column.
This happens, for example, when you copy and paste a symbol in order to change the details in the
copy slightly.
Identification of Ambiguous Symbols
In the symbol table, ambiguous symbols are identified by highlighting them graphically (color, font).
This change in their representation means they still require editing. You can either display all
symbols or filter the view so that only unique or ambiguous symbols are displayed.
Making Symbols Unique
An ambiguous symbol becomes unique when you change the component (symbol and/or address)
which caused this status. If two symbols are ambiguous and you change one of them to make it
unique, the other one also becomes unique.