I’m trying to connect to a CompactLogix PLC running v20.19 firmware.
I am able to connect to the PLC successfully and browse the tags. However when I try to read tag I get a Value of null and a Quality of bad. I tried this using the Quick Client in the Gateway and also creating a tag in the Designer.
My device connection is showing it is connected, and I did use the Allen-Bradley CompactLogix (Legacy) driver for this connection.
The log entry for this error is shown in the image below.