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activex interrupts send invalid data.


Im using an external activeX DLL from which I need to receive interrupts. I used the AutomationOpen block and then polled for interrupts using "Wait On ActiveX Event" block. The interrupt does arrive, yet in it's data variant is written

"OLE Variant

Variant Type -> VT_ILLEGAL"

The interrupt DATA should be of the following form:

DATAArrived(APP_SNAP_RX* stSnapRX,typAdditionalParams* AdditionalParameters)

What does it meens, and why can't I cast it using "Variant to DATA" block.

Another thing,
When using "InvokeNode" on the ActiveX DLL one of the methods is grayed out. Why? and How can i change it?

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Hi Yuval,

I have a couple of questions for you. Have you been successful using this DLL in another environment (other than LabVIEW)? Did you create this DLL? Is it producing an error or just incorrect data? If you want to include the DLL and a small VI, I can take a look at it.

Travis H.
National Instruments
Travis H.
National Instruments
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