New OPC-HDA capability; what module?

Hi all,

Does the new OPC-HDA capability in 7.7 reside in the OPC COM module, or somewhere else? If in the COM module, does that mean the HDA implementation, like DA, is not multi-platform (and thus won’t work on Linux or OSX systems)?


Norm Petterson

I understand this is a different version of the OPC-COM module (DA+HDA), with the same restriction.
I’ve been told that in the future there will be similar historical access in OPC-UA as there is in OPC-HDA, when the OPC Foundation releases the specs.

Ivan got it right.

The OPC-COM module contains both OPC-HDA and OPC-DA functionality. OPC-HDA is activated with an additional license parameter.

Because of the COM based nature of classic OPC (DA and HDA), yes, this module only works on Windows.

Historical access through UA is something we’d love to do, but there’s zero demand for it because as far as I know, no historians are supporting it yet.


I believe the Beckhoff Twincat OPC-UA has full support for HDA and is something I could really do with using, would be willing to help in setting this up with you to test…

That’s good to know, and we appreciate the offer. I’m honestly not sure when we’ll get to start working on history support for UA, but we’ll post back here when we know more.