Modbus TCP tags switch to bad quality

When I add only HRFxxxx tags, they are read with a good quality. But as soon as I add a tag with an HRI address, all the tags switch to quality bad.

Only HRF tags:

With a new HRI tag:

It’s probably the address offset, not the DataType.

Try turning the “Span Gaps” setting off.

Thank you, you are absolutely right.

In the Modubs TCP device, click Show advanced properties and uncheck the Span gaps checkbox

It works instantanely

So, what’s happening is in between the old registers you had configured and this new one there are some registers the device does not have defined, and instead of returning 0 or some other default value when they are read, the device is either returning an error code or just ignoring the request.

Disabling Span Gaps prevents these intermediate unaddressed registers from being read, at the cost of there being more requests in total needed to get the registers you are subscribed to.

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