array/buffer handle

[mhn05]

Hi,

I am trying to program a DT9834 data translation board for continuous analog input operation. I am using its ActiveX (DTx-EZ) in Labview 8.5. I should create an array/buffer and pass its handle to ActiveX's queue property. How can I get the handle of the array that I created?

Thanks for comments and help.

[smercurio_fc]

You can't. At least not directly in LabVIEW. You would need to create a wrapper DLL and use the memory manager functions.

[mhn05]

Thanks for the answer. As I am fairly new with Labview, I guess it doesn't seem to be a quick solution for me. Is there any online documentation for these (creating wrapper dll and memory functions) that I would give it a try.

Regards.

[smercurio_fc]

The method for creating the DLL is outside of LabVIEW so you would need to look at the documentation for whatever compiler you choose to use. Visual Studio is the most prevalent, for better or for worse.

There are several documents in the NI Knowledge Based on creating DLLs in Visual Studio. Here's a couple:

Using Existing C Code or a DLL in LabVIEW

Writing Win32 Dynamic Link Libraries (DLLs) and Calling Them from LabVIEW (a bit old, but still useful). 

There's also an extensive example that ships with LabVIEW. Search the Example Finder for "dll". 

There's also an entire section in the LabVIEW Help (Fundamentals -> Calling Code Written in Text-Based Programming Language)