However, what really seemed weird was that Rockwell HMI projects could do just this. So the question became, what trick was the factory using to make this possible?
I was fairly confident that referencing AOI local tags was do-able, but I thought I remembered there was some setting somewhere to enable it.
After hunting around in the software for awhile, I found the AOI Parameters and Local Tags screen did indeed have some advanced columns that were not displayed by default.
And the column and setting that I was confident was the culprit, external access, defaulted to off.
I selected it so it would be displayed, and found was the Rockwell example had the local tags set to “read/write,” while the clients had defaulted to “none.”
At this point it was as simple as changing the external access property from “none” to “Read/Write” and the HMI was now able to access the AOI's local tags.
I hope you've found this article about accessing AOI local tags helpful.
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Sincerely,
Shawn Tierney
Automation Instructor and Blogger
If you enjoyed my article, you may like my courses at TheAutomationSchool.com
It would be even more interesting if nested AOIs could also be accessed from the HMI.
Good morning edw1983,
I totally agree!
You know, I’ve never even tried – sounds like it doesn’t work 🙁
Sincerely,
Shawn Tierney