99BProgramming concepts
6.9 Debugging and testing the program
S7-1200 Programmable controller
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System Manual, 11/2011, A5E02486680-05
STEP 7 also provides a force table for "forcing" a tag to a specific value. For more
information about forcing, see the section on forcing values in the CPU (Page 648) in the
"Online and Diagnostics" chapter.
Note
The force values are stored in the CPU and not in the watch table.
You cannot force an input (or "I" address). However, you can force a peripheral input. To
force a peripheral input, append a ":P" to the address (for example: "On:P").
6.9.3
Cross reference to show usage
The Inspector window displays cross-reference information about how a selected object is
used throughout the complete project, such as the user program, the CPU and any HMI
devices. The "Cross-reference" tab displays the instances where a selected object is being
used and the other objects using it. The Inspector window also includes blocks which are
only available online in the cross-references. To display the cross-references, select the
"Show cross-references" command. (In the Project view, find the cross references in the
"Tools" menu.)
Note
You do not have to close the editor to see the cross-reference information.
You can sort the entries in the cross-reference. The cross-reference list provides an
overview of the use of memory addresses and tags within the user program.
●
When creating and changing a program, you retain an overview of the operands, tags
and block calls you have used.
●
From the cross-references, you can jump directly to the point of use of operands and
tags.
●
During a program test or when troubleshooting, you are notified about which memory
location is being processed by which command in which block, which tag is being used in
which screen, and which block is called by which other block.
Table 6- 6
Elements of the cross reference
Column
Description
Object
Name of the object that uses the lower-level objects or that is being used by the
lower-level objects
Quantity
Number of uses
Location
Each location of use, for example, network
Property
Special properties of referenced objects, for example, the tag names in multi-instance
declarations
as
Shows additional information about the object, such as whether an instance DB is
used as template or as a multiple instance