Omron CX-Supervisor, User Manual

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PLC Maintenance dialog box Appendix C Troubleshooting
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• As a test, use hardcoded values for parameters using known valid values
C.6.3 Runtime errors
If any script has correct syntax but generates an error at runtime e.g. trying to
open a file that does not exist, the error is recorded in the Error Log.
To troubleshoot further:
• To confirm the line causing the problem, temporarily comment it out and
see if the error is no longer reported.
• Display values using 'MsgBox'/'Message' command or using the
LogEvent command.
C.6.4 Design errors
The only remaining errors are when the script compiles and runs correctly, but
do not produce the expected results. These are typically errors in the design of
the script.
To troubleshoot further:
• Confirm path of execution using 'MsgBox'/'Message' in all conditional
branches.
• Display values using 'MsgBox'/'Message' command.
C.7 PLC Maintenance dialog box
The PLC Maintenance dialog box is launched by right clicking and selecting
PLC Maintenance. After choosing the PLC you can:
• Open and close the PLC
• See if there are errors
• Change the PLC Mode
• See the effect of optimisations as points are 'Disabled'
C.8 Database errors
The database connectivity can sometimes be problematic to configure
correctly. To troubleshoot CX-Supervisor database functionality:
• Try viewing and writing the data from another data source, for example
Microsoft Access application for mdb files etc.
• 'Connect' to the database from the Developer to check Table and Field
names can be correctly read. Remember to disconnect before running if
the provider doesn't support multiuser connections (like the Excel
provider)
• Note that every database function returns an error code to confirm if the
operation was successful. Always assign this to a temporary point and
after the call to check the value
• When database errors occur, try calling DBGetLastError(). This will give a
textual description of the problem. As these errors are standard there is
often information about the cause of these errors available on the Internet
- just search for the exact text of the error
C.9 How to create steps to reproduce
The first step in troubleshooting is creating steps to reproduce the problem.
Not only does this help understand the problem but is a requirement so that
your potential fixes can be tested with confidence. Computers and software
are guaranteed to perform the same way with the given data and so there are