What is it that allows ignition to view live tag values in the tag browser while having Designer open?
The tag browser is what you are referring to
Are you asking what makes this possible or how to see it?
Yes, Thank you.
I was curious about what underlying mechanism/programming makes it possible to have live tag values displayed in the Tag Browser shown in your screen shot. I figured it is apart of the OP UA server, but was not sure for example if I have a device reading battery voltage and can see it constantly updating down to one one-hundredth of a volt seemly not to skip any change.
OPC is one of the mechanisms that might be updating a tag, but this all happens on the Gateway.
Between the Designer and Gateway is an HTTP connection that is polling for updates using our own implementation. In 8.3 that becomes a WebSocket connection, but this is really just an implementation detail for most people.
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