Technical data

Displaying Reference Data
14.1 Overview of the Available Reference Data
Programming with STEP 7
Manual, 05/2010, A5E02789666-01 311
14.1.1 Cross-Reference List
The cross-reference list provides an overview of the use of addresses within the S7 user program.
When you display the cross-reference list you obtain a list of the addresses of memory areas input
(I), output (Q), bit memory (M), timer (T), counter (C), function block (FB), function (FC), system
function block (SFB), system function (SFC), I/O (P) and data block (DB), as used in the S7 user
program along with their addresses (absolute address or symbol) and usage. It is displayed in an
active window. The working window's title bar shows the name of the user program to which the
cross-reference list belongs.
Every line in the window corresponds to a cross-reference list entry. The search function makes it
easier for you to find specific addresses and symbols.
The cross-reference list is the default view when you display reference data. You can change this
default.
Structure
A cross-reference list entry consists of the following columns:
Column Content/Meaning
Address (symbol) Address
Block (symbol) Block in which the address is used
Type Whether a read (R) and/or write (W) access to the address is involved
Language Information on the programming language used to create the block
Location Double-click the location field to jump to the location of use for the selected address.
The Block, Type, Language and Location columns are displayed only if the corresponding
properties were selected for the cross-reference list. This block information varies, depending on
the programming language the block was written in.
You can set the column width in the cross-reference list shown on the screen as required using the
mouse.
Sorting
The cross-reference list default option is to sort by memory areas. If you click a column header with
the mouse, you can sort the entries of this column by the default sort criteria.
Example of Cross-Reference List Layout
Address (symbol) Block (symbol) Type Language Location
I1.0 (Motor on) OB2 R STL Nw 2 Inst 33 /0
M1.2 (MemoryBit) FC2 R LAD Nw 33
C2 (Counter2) FB2 FBD Nw2