DLL C/C++ syntax for Call Library Function Node

Hello,
I am interested in calling DLL from Labview and found several intersting tutorials on the Call Library Function Node. One interesting tutorial is Building a DLL with Visual C++ http://zone.ni.com/devzone/cda/tut/p/id/3056
One can notice in the example presented in this tutorial that the parameters that are outputs of the exported function are of type pointers. And I am curious about the theory behind this.
I looked also at the example in LabVIEW Call DLL.vi and it seems that all outputs are pointers to the desired data type.
I tried to write a short code where I assign a new value for one parameter in the export function. But this value is not updated in Labview. To make it clear: assume 50 is passed to an input parameter (on the left side of the Call Lib func Node). In the function, i assign 100 to this variable and expect this value on the output in Labview (right side indicator of Call Node) but the output remains 50.
I am trying to change my code but i get errors in linking (compiling is ok) that I cannot understand. LINK : fatal error LNK1168: cannot open Debug/DoseDLL.dll for writing
Error executing link.exe.
I don't get any error with the code provided in the above tutorial so i am trying to reproduce a similar code...
Thank you

Hello,
Please find attached the source code in C, the DLL and the vi.
you notice in the C code that I set variable dose=100 and this is the value I would like to export as an output for labview (right side of Node) for whatever value in the input (i put 50 for input dose). In the current code, the same value of input dose (50) is passed to the output (i assume it has to do with the reference ?). The idea is that variables dose and rate should be set/calculated in the DLL function.
Thank you!
Attachments:
DoseDLL3.cpp ‏1 KB
DoseDLL.vi ‏8 KB

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Execution time for Call Library Function Node

I am experimenting with the Call Library Function Node block in LabVIEW and am curious if it should be running faster than what I'm seeing. For testing purposes, I have compiled and transfered to my RT target the .out file from the KB article http://digital.ni.com/public.nsf/allkb/81D1172E3C28A5E4862575CC0076A230 (I'm using the vxworks 6.1 version). The function in the .out file just multiplies two inputs together, adds a constant, and returns the result. I have put this inside a 1 kHz timed loop with a commanded period of 1 ms and via the Ticks(ms) block and shift registers I calculate the amount of time per loop execution. This process is apparently taking 5 ms per cycle and to me that seems slow. Is that roughly the correct execution time for this kind of setup? I will attach my test .vi file.
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Windows 7
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NI-cRIO 9024 with NI-RIO 3.4.0
Solved!
Go to Solution.
Attachments:
test DLL.vi ‏31 KB

First off, the way you are doing timing isn't necessarily accurate because you don't know when the tick count VI is being called. For example, if it gets called on one iteration after your call library node executes, and the next iteration it gets called before the CLFN it executes, the subtraction doesn't include the call of the CLFN so you aren't seeing the true time it is taking for the dll to be called.
Where it says "error" on the top left hand corner of your loop. left click and choose previous iteration timing. Also, do you have the ability to choose a 1 Mhz clock? Are you sure it's actually being run on the RT and not on your PC? Running it on the PC would definitely make it difficult to execute at a 1 kHz rate.
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Hi,
Using LV2012
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Hello Hiren,
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When I use Call Library Function Node in real time, is the DLL loaded once for all or load every time it is called?

When I use Call Library Function Node in real time, is the DLL loaded once for all or load every time when it is called?
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Solved!
Go to Solution.

qing_shan61 wrote:
When I use Call Library Function Node in real time, is the DLL loaded once for all or load every time when it is called?
Once
qing_shan61 wrote:
I have a time critical real time application, in which I use a piece of DLL function developed by C++. It is OK?
OK
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Also for real-time application you need real-time OS.
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Dear all,
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Most of the times an enum is just a U8/U16/U32, internally so probably you can call it with just a U8/U16/U32 or something. For the correct value you have to look at the definition.
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I'm trying to build a LV PDA app that calls an external DLL file built using embedded visual C. When configuring the Call Library Function node I select the stub DLL, configure the I/O parameters and select OK. When the configuration dialog closes I get the following error:
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Hello -
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Help to make opencv's dll and LabVIEW's Call Library function node understanding each others

Hi, i have a little problem trying to use a C++ opencv's dll in labview. I wrote a really simple and stupid dll just to try to understand how it works the call library function node. Here the header code:
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class GENERICDLL_API CGenericDLL {
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// Generic DLL.cpp: definisce le funzioni esportate per l'applicazione DLL.
#include "stdafx.h"
#include "Generic DLL.h"
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>
#include <string.h>
#include <stdio.h>
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#include <opencv/highgui.h>
using namespace cv;
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GENERICDLL_API int opencv(int a)
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i can call all the three simple functions in labview with this easy code. No problem at all. If i uncomment the line "Mat image;" the call library function node doesn't work and i receive the error:
"The library specified for this node cannot be found or cannot be loaded. Right-click the Call Library Function node and select Configure, then choose the correct library name or path."
I think that is a problem of dependencies between opencv libraries but i dont know how to manage this. Any ideas?
Thank you for yours time,
Francesco.

Hello Francesco,
I'm having exactly the same problem as you. I created a DLL that I can easily access from LabView. If I add one line and include "imgproc.hpp" (the only one I need), then LV gives me the same error you had. I read the thread Loura linked to, but I don't see how people actually take care of the dependecies (Klemen's examples did not work for me for the same reason, even though I recompiled the .cpp). Could you explain in detail what you did to make it work?
Thanks

What is the exact syntax for calling remote function module.

Hi to all
1.....what is the exact syntax for calling remote function module.?
Thanks and regards,
k.swaminath reddy

hi
good
Lets do simple example where you will first create a RFC in one server (say A) and create normal program in othere server (say B). Finally you will call the RFC in A from B.
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1. log on to server A
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data tot type i.
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reward point if helpful.
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[HELP] Call Library Function Node...

I have a DLL which has a function as follows:
int GetMessageNameNumber (char* messageName [], const int MessageNumber);
The function is used thus:
char *MessageName = NULL;
int MessageNumber = 0;
error = HL1553API_GetMessageNumberName (&MessageName, MessageNumber);
MessageName will then contain the message name as a string.
I having the devils own job trying to wrap this into a Labview module. I have a Call Library function node for the above function, but I am not sure what to set the "MessageName" parameter too! I have tried Array of signed 8-bit integers, Adapt to Type, Array Data Pointer and then passed in a String array. Whatever I do results in LabView crashing. I know HL1553API_GetMessageNumberName works, because if I call it directly in TestStand it works fine. I need it LabView though!
Any ideas?
Christopher Povey
Senior Test Systems Engineer for BAE Systems.
Solved!
Go to Solution.

In C a pointer to a string or an array of strings are completely ambigues.
char ** something ===== char * something [].
You can not tell the two apart from the syntax but only from the documentation or from an example showing how the function is called. A C compiler treats the two equal in terms of access (but a C++ compiler will make a syntactic distinguishment when syntax checking code, resulting in possible compile warnings when prompted to use a sufficiently high warning level.)
The sample shows that this is not an array of strings that gets allocated by the caller and passed to the function, but a string pointer that gets passed by reference. As such the function will allocate a pointer and return it (a highly non-standard C practice at least for strings). This automatically begs the question when and how will this pointer be deallocated? The documentation for that function should document the memory manager call used to allocate that pointer and also point out the function to call to deallocate it. Ideally the library (DLL) provides a specific exported function for that purpose.
Assuming everything I have talked about so far is clear and available you have to trick LabVIEW a bit. You have to configer a pointer sized integer that gets passed by reference. Now this integer in the diagram IS in fact your string. If you only need to pass this pointer to other Call Library functions you are already done. Otherwise if you need to access the contents of that string from the LabVIEW diagram, you have to copy the information of that string pointer into a real LabVIEW string.
One way to do that is to use the MoveBlock() C function export that LabVIEW exports itself. I have explained this several times here on this forum and a search for MoveBlock will without doubt uncover those posts.
Another slightly better way is to use the LStrPrintf() function that LabVIEW also exports. For that you configure a Call Library function as follows:
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Function name: LStrPrintf
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Threading: both are possible but the function is thread safe so just use reentrant
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1st parameter: LabVIEW string handle, passed by value
2nd parameter: C string pointer
3rd parameter: pointer sized integer, passed by valu
Wire an empty string constant to the first parameter.
Wire a constant containing the text "%s" without quotes to the 2nd.
Wire your string pointer to the 3rd
On return the function will either return 0 as return value and the contents of the string on the output side of the 1st parameter or a non-zero return value indicating an error.
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a division of Test & Measurement Solutions

Call library function node with array of clusters using array data pointer

Hello all.
I am writing a LabVIEW wrapper for an existing DLL function.
The function has, as one of its parameters, an array of structs. The struct is very simple, containing two integers. I am using the call library function node to access it.
In Labview I created an array of clusters, where the cluster has two 32-bit integers as its members. So far, so good.
Now I have to pass this in to the Call Library Function Node. Here I am running into trouble.
I have used The topic in LAVA and The topic in the knowledge base as my primary sources of information, though I have read a bunch of forum topics on the subject too.
I do understand that I could write a new function which takes as a parameter a struct with the size as the first member and an array as the second, and I might just do this and have it call the regular function, but I was hoping to do it more simply.
According to the C file which LabVIEW generates for me from the CLFN when I choose "Adapt to Type" and "Array Data Pointer", the prototype it is expecting is:
int32_t myFunc(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, void data[], int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
And the prototype of the function in my DLL is
int borland_dll myFunc(DWORD handle, usint channel,
int FIFOnumber, struct mStruct *data, int numWords, int *actualLoaded, int *actualStartIndex);
This looks like a match to me, but it doesn't work (I get garbage in data). From the topic in LAVA referenced above, I understood that it would work. It does not.
If I cast data to the pointer-to-pointer I get when I generate c code by wiring my struct to a CIN and generating, then I seem to get what I expect. But this seems to work when I choose "pointers to handles" too, and I would expect array data pointer to give a different result.
Is there any way to get this to work directly, or will I have to create a wrapper? (I am currently using LabVIEW 2011, but we have customers using 2009 and 2012, if not other versions as well).
Thank you.
Batya
Solved!
Go to Solution.

OK, here is more detailed information.
I have attached the VI.
This is the code from the "C" file created by right-clicking the CLN and creating a "C" file.
When the parameter in the CLN is set to "array data pointer":
/* Call Library source file */
#include "extcode.h"
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, void data[], int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, void data[], int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex)
/* Insert code here */
When the parameter is "pointers to handles":
/* Call Library source file */
#include "extcode.h"
/* lv_prolog.h and lv_epilog.h set up the correct alignment for LabVIEW data. */
#include "lv_prolog.h"
/* Typedefs */
typedef struct {
int32_t control;
int32_t data;
} TD2;
typedef struct {
int32_t dimSize;
TD2 data[1];
} TD1;
typedef TD1 **TD1Hdl;
#include "lv_epilog.h"
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex)
/* Insert code here */
When the parameter is set to "handles by value":
/* Call Library source file */
#include "extcode.h"
/* lv_prolog.h and lv_epilog.h set up the correct alignment for LabVIEW data. */
#include "lv_prolog.h"
/* Typedefs */
typedef struct {
int32_t control;
int32_t data;
} TD2;
typedef struct {
int32_t dimSize;
TD2 data[1];
} TD1;
typedef TD1 **TD1Hdl;
#include "lv_epilog.h"
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex);
int32_t Load_Transmit_FIFO_RTx(uint32_t handle, uint16_t channel,
int32_t FIFOnumber, TD1Hdl *data, int32_t numWords, int32_t *actualLoaded,
int32_t *actualStartIndex)
/* Insert code here */
As to the DLL function, it is a bit more complicated than I explained above, in the current case. My VI calls the function by this name in one DLL, and that DLL loads a DLL and calls a function (with the same name) in the second DLL, which does the work. (Thanks Rolfk, for helping me with that one some time back!)
Here is the code in the first ("dispatcher") DLL:
int borland_dll Load_Transmit_FIFO_RTx(DWORD handle, usint channel, int FIFOnumber, struct FIFO_DATA_CONTROL *data, int numWords, int *actualLoaded, int *actualStartIndex)
t_DispatchTable *pDispatchTable = (t_DispatchTable *) handle;
int retStat = 0;
retStat = mCheckDispatchTable(pDispatchTable);
if (retStat < 0)
return retStat;
if (pDispatchTable->pLoad_Transmit_FIFO_RTx == NULL)
return edispatchercantfindfunction;
return pDispatchTable->pLoad_Transmit_FIFO_RTx(pDispatchTable->handlertx, channel, FIFOnumber, data, numWords, actualLoaded, actualStartIndex);
borland_dll is just "__declspec(dllexport)"
The current code in the DLL that does the work is:
// TEMP
typedef struct {
int control;
int data;
} TD2;
typedef struct {
int dimSize;
TD2 data[1];
} TD1;
typedef TD1 **TD1Hdl;
// END TEMP
int borland_dll Load_Transmit_FIFO_RTx(int handlertx, usint channel, int FIFOnumber, struct FIFO_DATA_CONTROL *data, int numWords, int *actualLoaded, int *actualStartIndex){
struct TRANSMIT_FIFO *ptxFIFO; //pointer to transmit FIFO structure
usint *pFIFOlist; //pointer to array of FIFO pointers to FIFO structures
int FIFOentry, numLoaded;
usint *lclData;
usint nextEntryToTransmit;
// TEMP
FILE *pFile;
int i;
TD1** ppTD = (TD1**) data;
TD1 *pTD = *ppTD;
pFile = fopen("LoadFIFOLog.txt", "w");
fprintf(pFile, "Starting Load FIFO with %d data words, data pointer 0x%x, with the following data&colon; \n", numWords, data);
for (i = 0; i < numWords; i++) {
fprintf(pFile, "%d: control--0x%x, data--0x%x \n", i, data[i].control, data[i].data);
fflush(pFile);
fprintf(pFile, "OK, using CIN generated structures: dimSize %d, with the following data&colon; \n", pTD->dimSize);
for (i = 0; i < numWords; i++) {
fprintf(pFile, "%d: control--0x%x, data--0x%x \n", i, pTD->data[i].control, pTD->data[i].data);
fflush(pFile);
// END TEMP
if ((handlertx) <0 || (handlertx >= NUMCARDS)) return ebadhandle;
if (cardrtx[handlertx].allocated != 1) return ebadhandle;
pFIFOlist = (usint *) (cardrtx[handlertx].segaddr + cardrtx[handlertx].glob->dpchn[channel].tr_stk_ptr);
pFIFOlist += FIFOnumber;
ptxFIFO = (struct TRANSMIT_FIFO *)(cardrtx[handlertx].segaddr + *pFIFOlist);
//use local copy of ptxFIFO->nextEntryToTransmit to simplify algorithm
nextEntryToTransmit = ptxFIFO->nextEntryToTransmit;
//on entering this routine nextEntryToLoad is set to the entry following the last entry loaded
//this is what we need to load now unless it's at the end of the FIFO in which case we need to wrap around
if ( ptxFIFO->nextEntryToLoad >= ptxFIFO->numEntries)
*actualStartIndex = 0;
else
*actualStartIndex = ptxFIFO->nextEntryToLoad;
//if nextEntryToLoad points to the last entry in the FIFO and nextEntryToTransmit points to the first, the FIFO is full
//also if nextEntryToLoad == nextEntryToTransmit the FIFO is full and we exit without loading anything
if (( (( ptxFIFO->nextEntryToLoad >= ptxFIFO->numEntries) && (nextEntryToTransmit == 0)) ||
( ptxFIFO->nextEntryToLoad == nextEntryToTransmit)) && (ptxFIFO->nextEntryToLoad != INITIAL_ENTRY)){
*actualLoaded = 0; //FIFO is full already, we can't add anything
return 0; //this is not a failure, we just have nothing to do, this is indicated in actualLoaded
numLoaded = 0;
lclData = (usint *)data; //must use 16 bit writes to the module
//conditions are dealt with inside the for loop rather than in the for statement itself
for (FIFOentry = *actualStartIndex; ; FIFOentry++) {
//if we reached the end of the FIFO
//if the module is about to transmit the first element of the FIFO, the FIFO is full and we're done
//OR if the module is about to transmit the element we're about to fill in, we're done - the
//exception is if this is the first element we're filling in which means the FIFO is empty
if ((( FIFOentry >= ptxFIFO->numEntries) && (nextEntryToTransmit == 0)) ||
((FIFOentry == nextEntryToTransmit) && (FIFOentry != *actualStartIndex) )){
*actualLoaded = numLoaded;
//set nextEntryToLoad to the end of the FIFO, we'll set it to the beginning next time
//this allows us to distinguish between full and empty: nextEntryToLoad == nextEntryToTransmit means empty
ptxFIFO->nextEntryToLoad = FIFOentry;
return 0;
//we reached the end but can continue loading from the top of the FIFO
if ( FIFOentry >= ptxFIFO->numEntries)
FIFOentry = 0;
//load the control word
ptxFIFO->FifoData[FIFOentry * 3] = *lclData++;
//skip the high of the control word, the module only has a 16 bit field for control
lclData++;
//now put in the data
ptxFIFO->FifoData[(FIFOentry * 3) + 2] = *lclData++;
ptxFIFO->FifoData[(FIFOentry * 3) + 1] = *lclData++;
numLoaded++;
//we're done because we loaded everything the user asked for
if (numLoaded >= numWords) {
*actualLoaded = numLoaded;
ptxFIFO->nextEntryToLoad = FIFOentry+1;
return 0;
//if we reached here, we're done because the FIFO is full
*actualLoaded = numLoaded;
ptxFIFO->nextEntryToLoad = FIFOentry;
fclose (pFile);
return 0;
As you can see, I added a temporary diagnostic with the structures that were created in the "Handles by value" case, and print out the data. I see what is expected, whichever of the options I pick in the CLN!
I understood (from the information in the two links I mentioned in my original post, and from the name of the option itself) that "array data pointer" should pass the array of data itself, without the dimSize field. But that does not seem to be what is happening.
Batya
Attachments:
ExcM4k Load Transmit FIFO.vi ‏15 KB

How to implement a callback function using LabView's Call Library Function Node?

I am trying to call a fuction from a SDK.dll library using the Call Library Function Node. The SDK was provided to
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                    SdkPropertyEvent        inEvent,
                    SdkPropertyID           inPropertyID,
                    SdkUInt32               inParam,
                    SdkVoid *               inContext );
Thanks for your help.
Alejandro
Solved!
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alejandroandreatta wrote:
I am trying to call a fuction from a SDK.dll library using the Call Library Function Node. The SDK was provided to
me and I do not have the source code, just the .dll and .h files.
The SdkSetPropertyEventHandler function has a callback fuction as one of its parameters. How do I implement the
callback using the CLF node? I am a good LabView programmer but this is my first time using the Call Library
Function Node. I have read all the info I can find on NI's web site and the discussion board but cannot figure
this one out. I am using LabView 8.6.
Basically you do not do that. LabVIEW does not know pointers and certainly not function pointers. What you should do instead is writing a C DLL that implements the callback and also exports a function to be called by LabVIEW that translates between the callback and a LabVIEW user event. Look for PostLVUserEvent() here on the NI site to find examples how to do that.
Rolf Kalbermatter
Message Edited by rolfk on 02-11-2009 08:00 PM
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

Call Library Function Node not Supported

Hai,
I have question to ask to NI members. I get an error said " Call Library Function Node 'LVASPT_WA.*ptDecimationFilterH':Node not supported". I use the call library function node in the FPGA.VI in my design. My question is, is it the function cannot used in FPGA.VI? I try to search a similar thread and find the manual but still can't find the answer. Anyone please clarify it to me. Thanks in advance.

You cannot use Call Library Function Node in FPGA. The FPGA is hardware - it has no way to call an external library. If it is not immediately obvious why it's impossible for the FPGA to call a DLL, you should spend some time understanding what a FPGA is.
You can integrate FPGA code written outside the LabVIEW environment, but that's not the same as calling a DLL.

Call Library Function Node: library not found or failed to load

Hello,
I had a VI that could not find some of the dll functions it needed. It works on one machine and not on another. So foolishly I copied the dll in question from the working machine and pasted it over the one on the non-working machine.
Now all my math functions are broken on the machine I copied the dll too. The error is "Call Library Function Node: library not found or failed to load"
And if I try to relink in the VI I get "Error loading C:\National Instruments\LabVIEW 8.2\resource\lvanlys.dll" A dynamic link library (DLL) initialization routine failed."
I tried a repair labview and that did not help.
I tried uninstall and reinstall labview and that did not help!
Please help me fix this!
Version 8.2
dll: C:\National Instruments\LabVIEW 8.2\resource\lvanlys.dll
Jim

What library did you first copy?
Also lvanlys.dll depends on the Intel Math Kernel Library that gets installed in a different location "C:\Program Files\National Instruments\Shared\MKL".
This Intel Math Kernel Library again depends on the Visual C runtime libraries. Most likely you replaced one of those runtime libraries somehow and now the Math Kernel Library (MKL) fails to initialize which causes thelvanlys.dll to fail its load.
Without a good view on your system and what other NI software you have installed it is very hard to recommend a good way of proceeding. There are various versions of the MKL used by various versions of NI products and just deleting the entire MKL folder might get you into trouble with other NI tools.
Deinstalling everything from NI, deleting the entire National Instruments folder and then reinstalling what you need would be the most safe proceeding.
And next time don't just copy some Visual C runtime libraries between machines. Their dependencies are complicated at the least and simply not graspable by us mere mortals. Use the according C runtime installer for the version you need as that installer will take care of installing the right versions of C runtime components and registering everything proberly so you do not usually run into problems with other applications using different versions of the C runtime.
Message Edited by rolfk on 03-01-2010 10:26 AM
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

Call library function node - function not found

When creating a DLL I get a the Labview error "Call Library Function Node "LabviewReceiverDLL.dll:readDataJ1939Data' Function not found. Everything looks correct to me and this used to work, though I've changed computers since then.
This is the beginning of my C++ code just to show my function name. I've also attached the Call Library Function Window to show my setup.
Thank you in advance for your help.
#include"StdAfx.h"
#include<iostream>
/* Call Library source file */
extern"C"__declspec(dllexport)unsignedint readDataJ1939Data(unsignedint, unsignedint, unsignedchar, unsignedchar* canData, unsignedchar* path);
unsigned int readDataJ1939Data(unsignedint ulTimeStamp, unsignedint ulIdentifier, unsignedchar uiDataCount, unsigned char* canData, constchar* path)
Solved!
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Attachments:
Call Library Function.png ‏192 KB

You mention that you have changed computers and that it used to work before.
Could it be that there is another (older) copy of the DLL on this computer, and LabVIEW is loading the wrong one?
The simplest way to check is to close your VI and delete the one you are expecting it to use. Then open the VI again; if LabVIEW doesn't ask you where the DLL is, it is loading it from somewhere else.
Batya

Call library function node: function not found in library

I'm using Labview 6.1 and Windows XP. I am trying to open some code, but it opens up with a broken arrow. The error is Call Library Function Node:function not found in library. Tried to configure the node, but no change. Moved the DLLs to various directories (keeping them together) but again no change.
This code has been compiled and is working fine. I'm just trying to run the source code to make some modifications. Any suggestions?
Thanks
CarlosV

Thanks for the suggestions. Tried it but had the same results. The library I'm using is hpe1413_32.dll.
One thing I forgot to mention....doing a configure on the node, it comes up with the library: hpvscp32.dll and the function: hpe1413_error_message
The function doesn't exist in the library. So I set the path to hpe1413_32.dll which does contain the function.
After closing the configuration window and opening it up again, the library shown is hpvscp32.dll
From what I can tell, there are three libraries involved:hpe1413_32.dll, hpe141332v.dll, and hpvscp32.dll
Thanks again.
Carlos

DLL C/C++ syntax for Call Library Function Node

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