Get data from DDE interface


Is anyone had a successful experience with getting data from DDE server into Ignition directly?

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I was wondering the same thing. I have a toolset developed outside of Ignition in Python 3.9, but any functions that need to write to tags needs to be done in the script console / Ignition screen tools which is not ideal :confused: If I could do this in my tool via DDE or other that would be awesome

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DDE is a pure Windows COM technology. Incompatible with Java. Which is why Ignition has special native drivers for OPC/DA–another COM technology. Don’t hold your breath.

The tool for external access to Ignition APIs is WebDev. I’m sure y’all have heard of it.


True, but at $1600 it’s a bit far-fetched to use as a simple API :frowning: although I guess I could use it in trial mode as I’ll only use it every so often…

Kepware has a DDE client driver. Knock that down to $1497 for you.

Haha, still can’t access Ignition tags from there though, only the OPC-UA side

Yes you can kepware has OPC UA client driver too and has bridge mode to map two tags drivers but as you said before it is costly

I have never worked with DDE so I don’t know its capabilities before but can it connect to a database and put its data there, then you can configure Ignition to connect to the same database and share info that way? Or similar idea with text\csv files? Just floating ideas to get around a steep price tag if its not 100% necessary. Though imo webdev and an API would be the absolute cleanest way to do it.

The bridge, when I used it, was problematic.

I did find JDDE, but nothing new there since 2017.
DDE has been dying since Win95, but a lot of SCADA companies (I’m looking at you, Wonderware) hung their hat on it. Wonderware came up with NetDDE before M$ licensed it.

In my case there is APACS MOORE DCS system which provide data over DDE so no other option like database is valid for me.

Wow. And I thought I had some legacy systems. Doesn’t Matrikon have a direct driver?

Yes but the driver is costly and only work with windows 2003 and not 2000.
There is 16413 MBI/NMI PCI card that has driver only for windows 2000 and it comes with real-time IO server that converts MBUS data into DDE for Intouch.
Now I’m considering every possible like read direct from DDE that has no cost.