Pointer

[ClementT]

Hello,

Under LabView 7.0, I am using activeX to control my USB CCD camera with "method" and "property" nodes. One of the methods designed to retrieve data from my CCD asks for a pointer where it should send the data, but if I understand correctly, Labview does not allow the user do to such a thing (creating pointers). Is there any workaround, any way to give to my method the input (this long integer buffer) it requires? I hope I am clear enough, as all these things are not so clear to me.

Thanks in advance for you answers,
Clément

[bfarley]

If the function is expecting a pointer to an array (buffer), just wire in an array of the data type it expects.  The array must be initialized ie be as large as the function needs.

Bill F

Message Edited by bfarley on 05-03-2007 11:51 AM

[ClementT]

Thank you Bill for your answer.
Unfortunately, it does not seem to work : when I wire a 2D array of unsigned 16 bit integer, I get a broken wire, since my function expects a pointer, which is a 32 bit integer type element.
Am I missing something ?

Clément

[Richard_KEROMEN]

Hello,

Just a simple question : why don't you use the "NI-IMAQ for USB camera" ?  This will offer you a real compatibility and an easier way to develop you application. Now if you really require to use Active X controls let me know.

Regards

[ClementT]

Well, in fact I am brand new to the Labview world and I am not aware of the many possibility it offers, so maybe NI-IMAQ for USB camera is the right way to go ; I will look into it and report back here.

I originally used activeX controls because the vendor of my camera (an Apogee Alta camera) provided me with an API and a VI that initialized the camera and so on, so that I only had to modify it a little to have it do the things I wanted to. That was in an ideal world, obviously.

Thank you for your help,

Clément