Technical data

Programming with STEP 7
Manual, 05/2010, A5E02789666-01 309
14 Displaying Reference Data
14.1 Overview of the Available Reference Data
You can create and evaluate reference data to make it easier to debug and modify your user
program. You use the reference data for the following:
• As an overview of your whole user program
• As the basis for changes and tests
• To complement your program documentation
The following table shows which information you can extract from the individual views:
View Purpose
Cross-reference list Overview of the addresses in the memory areas I, Q, M, P, T, C, and DB, FB,
FC, SFB, SFC calls used in the user program.
Using the menu command View > Cross References for Address, you can
display all the cross-references including overlapping access to the selected
address.
Assignment list for inputs,
outputs, and bit memory
Overview of which bits of the addresses in the memory areas I, Q, and M, and
which timers and counters (T and C) are already occupied within the user
program; forms an important basis for troubleshooting or changes in the user
program
Program structure Call hierarchy of the blocks within a user program and an overview of the blocks
used and their nesting levels
Unused symbols Overview of all symbols which are defined in the symbol table but not used in
the parts of the user program for which reference data are available
Addresses without symbols Overview of all absolute addresses which are used in the parts of the user
program for which reference data are available but for which no symbol has
been defined in the symbol table
The reference data for the selected user program include all the lists in the table. It is possible to
create and display one or more of the lists for one user program or for more than one user
program.