Features For Debugging Your Program - Siemens SIMATIC S7-200 System Manual

S7-200 Programmable Controller System Manual

Features for Debugging Your Program

STEP 7--Micro/WIN provides several features to help you debug your program: bookmarks, cross
reference tables, and run mode edits.
Using Bookmarks for Easy Program Access
You can set bookmarks in your program to make it easy to move back and forth between
designated (bookmarked) lines of a long program. You can move to the next or the previous
bookmarked line of your program.
Using the Cross Reference Table to Check Your Program References
The cross reference table allows you to display the cross references and element usage
information for your program.
Cross
The cross reference table identifies all
Reference
operands used in the program, and
identifies the program block, network or
line location, and instruction context of
the operand each time it is used.
You can toggle between symbolic and
absolute view to change the
representation of all operands. representation of all operands.
Tip
Double-clicking on an element in the cross reference table takes you to that part of your
program or block.
Editing Your Program in RUN Mode
The S7-200 CPUs Rel. 2.0 (and higher) models support RUN mode edits. The RUN mode edit
capability is intended to allow you to make small changes to a user program with minimal
disturbance to the process being controlled by the program. However, implementing this capability
also allows massive program changes that could be disruptive or even dangerous.
Warning
When you download changes to an S7-200 in RUN mode, the changes immediately affect
process operation. Changing the program in RUN mode can result in unexpected system
operation, which could cause death or serious injury to personnel, and/or damage to equipment.
Only authorized personnel who understand the effects of RUN mode edits on system operation
should perform a RUN mode edit.
To perform a program edit in RUN mode, the online S7-200 CPU must support RUN mode edits
and must be in RUN mode.
1. Select the Debug > Program Edit in RUN menu command.
2. If the project is different than the program in the S7-200, you are prompted to save it. The
RUN mode edit can be performed only on the program in the S7-200.
3. STEP 7--Micro/WIN alerts you about editing your program in RUN mode and prompts you to
either continue or to cancel the operation. If you click Continue, STEP 7--Micro/WIN uploads
the program from the S7-200. You can now edit your program in RUN mode. No restrictions
on edits are enforced.
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Figure 8-1 Cross Reference Table