DLL routines

[ChrisM 24]

I am trying to write a routine to interface with a DLL on a PC which is
controlling a robot. This is something I have never done. Can anyone suggest
a good place to start from?

Yours sincerely, Chris McCrory Project Engineer
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[Kevin_work]

Chris McCrory wrote:

> I am trying to write a routine to interface with a DLL on a PC which is
> controlling a robot. This is something I have never done. Can anyone suggest
> a good place to start from?
>

Check the manual for more in depth info.
Basically all you need is a Call Library Function. Drop one on the diagram
right click and select configure. Fill in the information about the path to the
DLL
the name of the function and the input parameters and the return parameter
Once you wire this up all should be fine.

Kevin Kent

[Ed Bogart]

"Kevin B. Kent" wrote:

> Chris McCrory wrote:
>
> > I am trying to write a routine to interface with a DLL on a PC which is
> > controlling a robot. This is something I have never done. Can anyone suggest
> > a good place to start from?
> >
>
> Check the manual for more in depth info.
> Basically all you need is a Call Library Function. Drop one on the diagram
> right click and select configure. Fill in the information about the path to the
> DLL
> the name of the function and the input parameters and the return parameter
> Once you wire this up all should be fine.
>
> Kevin Kent

Ah yes, but it's the input parameters and the return parameters that are the hard
part. How do you know/find out what to they are if you didn't create the DLL?

Ed Bogart

[Kevin_work]

Ed Bogart wrote:

> "Kevin B. Kent" wrote:
>
> > Chris McCrory wrote:
> >
> > > I am trying to write a routine to interface with a DLL on a PC which is
> > > controlling a robot. This is something I have never done. Can anyone suggest
> > > a good place to start from?
> > >
> >
> > Check the manual for more in depth info.
> > Basically all you need is a Call Library Function. Drop one on the diagram
> > right click and select configure. Fill in the information about the path to the
> > DLL
> > the name of the function and the input parameters and the return parameter
> > Once you wire this up all should be fine.
> >
> > Kevin Kent
>
> Ah yes, but it's the input parameters and the return parameters that are the hard
> part. How do you know/find ou
t what to they are if you didn't create the DLL?
>
> Ed Bogart

Well yes that is the hard part.
1) Contact the vendor - this is the best way,
2) Use software tools to probe the dll - tricky at best
3) Guess - - could take quite some time and a number of reboots.

Your only real option is #1. If you don'y have any documentation on the DLL
you will have to get the vendor to supply it. They generally are willing to do this.

Kevin Kent

[Helen E. Kourous]

A way to get the *names* of the functions inside a DLL is to open it using QuickView
(under windows). (Shift-right-click)

Create a vi with the CIN (Code Interface Node) or the one right next to it that allows
you to talk to dll's - and double click on it; browse to the path where the dll of
interest is. Then type in a function name you found under the QuickView (see the Export
section) and you'll get a function prototype for the function of interest, which may or
may not be useful to you:

int grabFrame(uint devnum, long * buf)

This gets you a little farther anyway. The best is detailed function call parameter and
return value info from the manufacturer of course...

Good luck.
-Helen

"Kevin B. Kent" wrote:

> Ed Bogart wrote:
>

> > "Kevin B. Kent" wrote:
> >
> > > Chris McCrory wrote:
> > >
> > > > I am trying to write a routine to interface with a DLL on a PC which is
> > > > controlling a robot. This is something I have never done. Can anyone suggest
> > > > a good place to start from?
> > > >
> > >
> > > Check the manual for more in depth info.
> > > Basically all you need is a Call Library Function. Drop one on the diagram
> > > right click and select configure. Fill in the information about the path to the
> > > DLL
> > > the name of the function and the input parameters and the return parameter
> > > Once you wire this up all should be fine.
> > >
> > > Kevin Kent
> >
> > Ah yes, but it's the input parameters and the return parameters that are the hard
> > part. How do you know/find out what to they are if you didn't create the DLL?
> >
> > Ed Bogart
>
> Well yes that is the hard part.
> 1) Contact the vendor - this is the best way,
> 2) Use software tools to probe the dll - tricky at best
> 3) Gue
ss - - could take quite some time and a number of reboots.
>
> Your only real option is #1. If you don'y have any documentation on the DLL
> you will have to get the vendor to supply it. They generally are willing to do this.
>
> Kevin Kent