I have kind of a weird problem with a new Modbus TCP device. The device is configured and I’ve set up tags using address mapping. When I use the Quick Client and trigger a read, it reads fine. I’m monitoring traffic with Wireshark, and I see the connection, request, and response.
But in the Designer, the tags are all null with a quality of Unknown. I’ve tried using the address mapping syntax for the tag and also manual addressing, with and without the unit id. Wireshark shows no traffic on port 502.
Also, when I set up a subscription in Quick Client, it’s always null. But a single read works fine.
This is in Ignition 7.9.7.