Problem with tag Value Events - Value Change

[pturmel]

In gateway scope, the database connection name argument to runQuery is required.

Your except: can inspect/print/log the actual exception information via python's sys and/or traceback modules, though you will need a separate except: clause to capture java errors. See this example:

readBlocking and timeout exception

If the error was a direct throw of that TimeoutException, your except clause would work. But it is being wrapped in some other throwable (the TimeoutException add as the cause). I recommend this structure for this case: import java.lang.Throwable def someFunction(): try: system.tag.writeBlocking(.....) except java.lang.Throwable, t: # do something, including looking at t.cause except Exception, e: # do something with other python problems.

Note that any uncaught errors or logging or printing from gateway scope show up in the gateway log, not in the designer's console or client console. Printing, in particular, only goes to the text-format wrapper log.

{ Have you gone through the lessons in IA's Inductive University ? That would cover many of the basic concepts of Ignition and Python that are tripping you up. }