User`s guide

Building a VISA Application in Windows 2
Agilent VISA User’s Guide 25
Logging Error Messages
When developing or debugging your VISA application, you may want
to view internal VISA messages while your application is running. You
can do this by using the Event Viewer utility or the Debug Window.
There are three choices for VISA logging:
•Off (default) for best performance
• Event Viewer
•Debug Window
Using the Event Viewer
The Event Viewer utility provides a way to view internal VISA error
messages during application execution. Some of these internal messages
do not represent programming errors; they indicate events which are
being handled internally by VISA. The process for using the Event
Viewer is:
• Enable VISA logging from the Agilent IO Control by clicking the
blue IO icon on the taskbar and then clicking Agilent VISA Options
> VISA Logging > Event Viewer.
• Run your VISA program.
• View VISA error messages by running the Event Viewer. From the
Agilent IO Control, click Event Viewer. VISA error messages will
appear in the application log of the Event Viewer utility.
Using the Debug Window
When VISA logging is directed to the Debug Window, VISA writes
logging messages using the Win32 API call OutputDebugString(). The
most common use for this feature is when debugging your VISA