Help! Alias Topic in RsLinx Not switching!

Hello, i got 2 opc topics configured and working, now i created a third "virtual" topic in alias topic configuration that points to the 2 other topics (eth and df1), that has to switch if a comm problem occurs with the first topic.
the thing is that it is not working.
I am using this virtual topic with rsview, and works well ( the first topic being working ) but if i unplug the network, it does not switch to df1 automatically. Why? am i forgetting something?
PD. df1 works well if you use it directly.

Just as a test, can you configure "Switch on Bit" in the alias definition, and see if toggling that bit forces a topic switch?

well... just figured out how to put a bit "path" in that field, i copied the path from the data monitor of the processor.
i will test if changing that variable the topic switchs.
have to wait an hour to do it. I will post the results.
thanks rdrast!

Are you looking at topics in a CLX processor?
If so, don't use the switch on error option. You'll need to switch on command.

Still in trouble. I tried switching with command, but when asking for the Topic1@ispresent always return me error.

just for the record, i got a clx processor and to topics pointing to it. One going trough ethernet driver, and the other just df1.
I need to switch to df1 when the network gos down.

will apreciate any help.

The @ispresent item will only work if you configure the topic as a PLC-5 processor type. You COULD do this, and add another set of topics to RSLinx. But, I found a method that I like better:

Set up a timer or counter in your PLC that will always restart itself when it completes its cycle. Create a link in your HMI to monitor this freewheeling timer. If the timer stops updating or gives you an error value (RSView actually has a data error signal), switch topics.

You can monitor the ACTIVETOPIC tag in your HMI, if you like.

AK