"unsigned char** pImgData" How to call in LabVIEW

HI,
I am calling a DLL in LabVIEW8.5 by using "Call Library Function Node".
I can able to access all the functions and getting exact results.
But for the below function LabVIEW is crashing.
void SFCCU_GET_IMG_RAW_DATA(unsigned long *length,unsigned char** pImgData,unsigned int iCamObj)
According to the doccumentation of the dll provided, pImgData is 1D array.
I tried the same dll in VC++. I can able to acheive the result of he above function properly.
I attached the Call Library Function Node.vi's prototype with this mail what i have done. It seems to be correct.
But i dont know why its crashing. Please tell me wether i am calling properly or not.
if not, kindly suggest me how to overcome it.
Thanks in advance for the help,
Please help me,
Thanks,
Sams.
Attachments:
Prototype in LabVIEW.JPG ‏42 KB

Hi Sams,
Can you clarify what you mean by crash? Can you describe what happens? Do you get an error message? Is there anything different in how you are calling the function in LabVIEW versus VC++?
I look forward to your reply to help move this issue forward.
Regards,
Hillary E
National Instruments

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Calling a dll that has an unsigned char, unsigned char * in a function call

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dinks-
   Just some janitorial work first: when posting try and keep the spaces between lines to a minimal. Empty spaces just means less memory somewhere. To your question, I think some clarification is needed. Tell me if this is right, you have a dll that you are calling into LabVIEW using Call Library Function node and then trying to get this unassigned character.
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http://zone.ni.com/devzone/cda/tut/p/id/...
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A search yielded the following items that you may wish to peruse:
http://forums.ni.com/ni/board/message?board.id=170&message.id=261345&requireLogin=False
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Anyone know how to call a Labview dialog without the splash sceen popping up?

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http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=50650000000800000057450000&UCATEGORY_0=_8_&UCATEGORY_S=0&USEARCHCONTEXT_TIER_0=0&USEARCHCONTEXT_TIER_S=0&USEARCHCONTEXT_QUESTION_0=splash+teststand+click&USEA
RCHCONTEXT_QUESTION_S=0
http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=50650000000800000024420000&UCATEGORY_0=_8_&UCATEGORY_S=0&USEARCHCONTEXT_TIER_0=0&USEARCHCONTEXT_TIER_S=0&USEARCHCONTEXT_QUESTION_0=splash+teststand+click&USEARCHCONTEXT_QUESTION_S=0
Attachments:
TestModalDialog.seq ‏10 KB
ShowModalDialog.vi ‏37 KB
ShowDialog.vi ‏24 KB

Hi Mark,
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Regards
Ray Farmer

How to call Labview DLL from VB2005

Dear all expert,
I'm a student and very new in Labview programming.
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here I'm attach my Vi and really hope someone willing to help.
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Attachments:
bodeplot.vi ‏1049 KB

On Sep 17, 6:40 am, cckoh <[email protected]> wrote:
> Dear all expert,
> I'm a student and very new in Labview programming.
> Currently i have build a simple vi and need to convert it to dll so that i can call it from my VB.net. But the problem is how to call the labview dll from my VB.net?
>  
> I know we must declare function something like this,
>  
> Auto function Bodeplot Lib"..\\Bodeplot.dll" (Byval Val1 as double, Byval Val2 as double,...) as double
>  
> but how to determine Val1, Val2 (and so on) is input for which data?  if my vi have 10 input (frequency, Kc,Fcz,Fcp,Wzrhp,Wp,k,Wz,Beta and Operation) ? and how to select the output (my application have 3 possible output : magnitup loop,phase loop, and degree loop)
>  
> In addition, since I'm using Labview 8.0 , and as i know apllication  builder for this version cannot convert vi to dll which contain Mathscript (but unfortunely, my vi all use Mathscript), so really hope someone can help me to convert my vi to dll using Labview 8.2 (which remove this limitation).
>  
> here I'm attach my Vi and really hope someone willing to help.
>  
> Thank you.
>  
>
> bodeplot.vi:http://forums.ni.com/attachments/ni/170/272124/1/bodeplot.vi
If you insist on using Labview with your project then you should
consider using ActveX in place of using a dynamic link library to
interface to your VB.net code. You don't need "Application Builder"
if you use ActiveX. The Student, Basic and Full development versions
of Labview for Windows come with ActiveX capability. For more
information on ActiveX look up the subject ActiveX in Labview's Help
File.
Howard

JNI equivalent of an unsigned char *

Hi,
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I'm sorry , I'm not sure if I understand this correctly,
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How can I get an unsigned char string with nulls from a dll into LabVIEW 6i?

The following ethernet packet data is contained in an unsigned char * string returned from my dll (it's formatted on printing):
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Ethernet Dest: 01.E0.BB.00.00.15 Src: 00.E0.BB.00.DD.CC Type: 0x8868
000000: 01 E0 BB 00 00 15 00 E0 : BB 00 DD CC 88 68 48 41 .............hHA
000010: 00 E0 BB 00 DD CC 80 B3 : 00 00 FF FF 00 02 00 01 ................
000020: 01 00 F0 18 FF 7F 7F FF : FF 7F 7F FF FF 7F 7F FF ................etc., etc.
However, when I read this string into LabVIEW 6i, I only get the following:
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Excellent advice, this mostly works so I have some further questions:
I am just reading network traffic off my ethernet card right now, but here is what I get using my C program to test:
000000: 01 E0 BB 00 00 15 00 E0 : BB 00 DD CC 88 68 48 41 .............hHA
000010: 00 E0 BB 00 DD CC 80 B3 : 00 00 FF FF 00 02 00 01 ................
000020: 01 00 38 3C FF 7F 7F 7F : 7F 7F 7F FF FF 7F 7F FF ..8<............
000030: FF 7F 7F FF FF 7F 7F FF : 7F 7F 7F FF FF FF FF FE ................
000040: FE FF FF FF FF 7F 7F 7F : 7F 7E 7E 7F 7F 7E 7E FF .........~~..~~.
000050: 7F 7F 7F 7F FF 7F 7F 7F : 7F 7F 7F FF FF 7F 7E 7F ..............~.
000060: 7F 7F 7E 7F 7F 7E 7F FF : FF 7F FF FF FE FF FF FE ..~..~..........
000070: FF FF FF FF FF 7F 7F FF : FF 7F 7F FF FF FF FF FF ................
000080: FF 7F 7F FF FF 7F 7F FF : FF 7F 7F FF FF 7F 7F FF ................
000090: FF 7F 7F 7F FF 7F 7F 7F : 7F 7F 7F FF FF 7F 7F FF ................
0000A0: FF 7F 7F 7F 7F 7E 7E 7F : 7F 7F FF FF FF FF FF FF .....~~.........
0000B0: FF FF 7F FF FF 7F 7F FF : 7F 7F 7F FF FF 7E 7F FF .............~..
0000C0: FF FF 7F FF FF 7F 7F FF : 7F 7F 7F FF FF 7F 7F FF ................
0000D0: FF 7F 7F FF FF 7F 7F 7F : 7F 7F 7F FF FF FF FF FE ................
0000E0: FE FF FF FF 00 01 : ................
And here is what I get using LabVIEW to call the dll:
0015 00E0 BB00 DDCC 8868 4841 00E0 BB00 DDCC 80B3 0000 FFFF 0002 0001 0100 9600 7F7F 7F7E 7F7F 7F7F 7F7F 7F7F 7F7F 7F00 B405 4300 3300 0000 0000 0000 01E0 BB00 0015 00E0 BB00 DDCC 8868 4841 00E0 BB00 DDCC 80B3 0000 FFFF 0002 0001 0100 9600 7F7F 7F7E 7F7F 7F7F 7F7F 7F7F 7F7F 7F00 F405 1B04 0C04 0000 0000 0000 8000 0000 0000 0000 0800 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
The first thing I notice is that the first 4 bytes are chopped off, and after about 50 bytes, the data is corrupted until the sequence starts to repeat, but this time it starts with the missing 4 bytes and still corrupts after about 55 bytes.
I am expecting the data in LabVIEW to look very similar to the C data because the network packets I am grabbing are pretty consistant, only a couple bytes will vary between them, not the number I am seeing in LabVIEW.
Another side effect I'm seeing is that I can only run my labVIEW code once, if I try running it again it crashes with failures such as:
memory could not be "read"
For reference, I am opening and closing the network adapter inside the read function of my dll, but the pointer seems like it should be intact...
Attachments:
zListAdapters.vi ‏30 KB
listAdapters.dll ‏201 KB
Reading.dll ‏213 KB

How to call this dll point function by labview

Void SetCompStatusCallBack(void ((*CompStatusCallBack)(int id, int status, unsigned char conflict)))
Sets up callback function for getting component status.
Parameters:
* CompStatusCallback – entry point for callback function.
Return Value:
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left wrote:
Void SetCompStatusCallBack(void ((*CompStatusCallBack)(int id, int status, unsigned char conflict)))
Sets up callback function for getting component status.
Parameters:
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Return Value:
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Rolf Kalbermatter
Message Edited by rolfk on 01-26-2007 04:21 PM
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

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why did you classify this as byte? how do you did
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> I have a customer requirement for two LabVIEW executables. Based on
> their current setup, they need to run executable "A" or "B", both of
> which are under independent revision control. I have created a third
> "selection" executable that allows the operator to choose between one
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nd to
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