How do I pass a void *pointer to a dll in LabView

I did read previous posts on the matter and tried just about everything, inlcuding defining the pointer as a U32 int.
What I am trying to do is program FLASH using WindRiver VisionPROBE EST...
I do have some sucesses... )
I can open a connection to the EST, initialize it, start & stop the target. No problem here..
Here are some additional details:
I can't read memory, write to the target register or program the FLASH, yet. Any advice on how to get further with this? Typically, when doing this using WR's visionClick sw, we need to use a register file which sets up the target. I have not seen any reference to this in their API.
I can convert to CVI if necessary. I am using the dll's from WindRi
ver. I'd prefer keeping everything in LV, but LW-CVI is fine.
My problem is that I am not sure if I am passing void pointers back & forth correctly. For instance, I need to call a function which returns a status, as follows:
status = EST_WriteTargetRegister (long handle, Unsign int register, void * value)
How do I pass the "void * value" to the input of a Call Library FUnction Node. I did try "Adapt to type" which does give a "void * value", and I tried both "Handles by Value" & "Pointers to Handles".
When I change the input value to anything other than "Adpapt To Type", I get a violation error. >(
Has anyone successfully automated WindRiver's EST?
- Thanks -
JLV"

Hi,
Have you tried passing a I32, but selecting "Pointer To Value"?
Is there any description about the "void *pointer"? Could it be a callback
function?
Regards,
Wiebe.
"JoeLabView" wrote in message
news:[email protected]..
> I did read previous posts on the matter and tried just about
> everything, inlcuding defining the pointer as a U32 int.
>
> What I am trying to do is program FLASH using WindRiver VisionPROBE
> EST...
>
> I do have some sucesses... )
> I can open a connection to the EST, initialize it, start & stop the
> target. No problem here..
>
> Here are some additional details:
>
>
>
>
> I can't read memory, write to the target register or program the
> FLASH, yet. Any advice on how to get f
urther with this? Typically,
> when doing this using WR's visionClick sw, we need to use a register
> file which sets up the target. I have not seen any reference to this
> in their API.
>
> I can convert to CVI if necessary. I am using the dll's from
> WindRiver. I'd prefer keeping everything in LV, but LW-CVI is fine.
>
> My problem is that I am not sure if I am passing void pointers back &
> forth correctly. For instance, I need to call a function which
> returns a status, as follows:
>
>
> status = EST_WriteTargetRegister (long handle, Unsign int register,
> void * value)
>
>
> How do I pass the "void * value" to the input of a Call Library
> FUnction Node. I did try "Adapt to type" which does give a "void *
> value", and I tried both "Handles by Value" & "Pointers to Handles".
>
> When I change the input value to anything other than "Adpapt To Type",
> I get a violation error. >(
>
> Has anyone successfully automated WindRiver's EST?
>
> - Thanks -
>
> JLV"

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"Enrique" wrote in message
news:[email protected]..
> I see...
>
> After doing some research, it seems to me that there is no easy way to
> find out the type of data, other than looking at the header file and
> have documents like Using External Code in LabVIEW handy. The
> following information is from that document:
>
> LVBoolean is an 8-bit integer. 1 if TRUE, 0 if FALSE.
>
> LabVIEW specifies file refnums using t
he LVRefNum data type, the
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> the functions described in Chapter 6, Function Descriptions.
>
> I know you are creating a dll in LabVIEW, but I am pretty sure the
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> descriptor.
>
> From the header file, is can be deduced that TD1 is a cluster in
> LabVIEW.
>
> You are right in saying that "more details are needed on using the
> LabView DLL within LabView from National Instrument Technical
> Support.".
>
> Enrique

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