RTD wrapper functions do not work in Excel 2007

I sell an addin which links to a number of real time providers (eSignal,
market feed...) using a dll (written to the RTD standard). I use VBA
wrapper functions which in turn call the RTD dll. Works fine with Excel 2002
and Excel 2003. It does NOT work with Excel 2007 however. I've recompiled
the dll to ensure the VB 6.0 reference includes the 2007 libraries. If I use
the RTD function directly from a worksheet cell it DOES work. This shows the
dll is functioning correctly. However, when it's included in a VBA wrapper
function nothing happens. ie cell values are not updated. I've stipped the
dll down to the point where it simply displays the time -- ie a few lines of
code -- with the same result: wrapper functions do not work.

Wrapper functions are essential as asking users to use RTD direct is complex
and not a practical solution for average users. Has anybody else had a
problem with wrapper fucntions?

I forgot to mention that it's Excel 2007 beta 2.

"peterhoa" <[email protected]> wrote in message
news:[email protected]...
>I sell an addin which links to a number of real time providers (eSignal,
> market feed...) using a dll (written to the RTD standard). I use VBA
> wrapper functions which in turn call the RTD dll. Works fine with Excel
> 2002
> and Excel 2003. It does NOT work with Excel 2007 however. I've recompiled
> the dll to ensure the VB 6.0 reference includes the 2007 libraries. If I
> use
> the RTD function directly from a worksheet cell it DOES work. This shows
> the
> dll is functioning correctly. However, when it's included in a VBA
> wrapper
> function nothing happens. ie cell values are not updated. I've stipped
> the
> dll down to the point where it simply displays the time -- ie a few lines
> of
> code -- with the same result: wrapper functions do not work.
>
> Wrapper functions are essential as asking users to use RTD direct is
> complex
> and not a practical solution for average users. Has anybody else had a
> problem with wrapper fucntions?

peterhoa wrote:
> I forgot to mention that it's Excel 2007 beta 2.
>
> "peterhoa" <[email protected]> wrote in message
> news:[email protected]...
> >I sell an addin which links to a number of real time providers (eSignal,
> > market feed...) using a dll (written to the RTD standard). I use VBA
> > wrapper functions which in turn call the RTD dll. Works fine with Excel
> > 2002
> > and Excel 2003. It does NOT work with Excel 2007 however. I've recompiled
> > the dll to ensure the VB 6.0 reference includes the 2007 libraries. If I
> > use the RTD function directly from a worksheet cell it DOES work.

Sorry, no answer to your question but I can say that I see exactly the
same behaviour here: writing =RTD() directly in the worksheet cells
works fine but using a wrapper function returning
Excel.Application.WorksheetFunction.RTD() doesn't work. I can see that
in the latter case Excel calls my ConnectData() just as usual but
almost immediately thereafter it calls DisconnectData() -- without any
apparent reason. Even more surprizingly, it still calls RefreshData()
for the topic it just disconnected from.

The fact that =RTD() in the worksheet works makes me suspect that this
is a beta2 bug, I hope this wasn't a conscious design decision in Excel
2007, so I can only hope it's going to be fixed in the final version.

Regards,
VZ

The Microsoft beta team sent me an email acknowledging the problem:
"Thanks for the note. This is an issue we are aware of and that we are
working on."

They invited me to send them a test so I have sent them a simple test which
produces the problem. So hopefully it will be fixed in the final release.

Your description of the disconnect function in the RTD dll being called
immediately on loading ties in exactly with what I found and in the test I
sent Microsoft a message box pops up when that happens so it's very clear
what's going on.

Peter

<[email protected]> wrote in message
news:[email protected]...
> peterhoa wrote:
>> I forgot to mention that it's Excel 2007 beta 2.
>>
>> "peterhoa" <[email protected]> wrote in message
>> news:[email protected]...
>> >I sell an addin which links to a number of real time providers (eSignal,
>> > market feed...) using a dll (written to the RTD standard). I use VBA
>> > wrapper functions which in turn call the RTD dll. Works fine with
>> > Excel
>> > 2002
>> > and Excel 2003. It does NOT work with Excel 2007 however. I've
>> > recompiled
>> > the dll to ensure the VB 6.0 reference includes the 2007 libraries. If
>> > I
>> > use the RTD function directly from a worksheet cell it DOES work.
>
> Sorry, no answer to your question but I can say that I see exactly the
> same behaviour here: writing =RTD() directly in the worksheet cells
> works fine but using a wrapper function returning
> Excel.Application.WorksheetFunction.RTD() doesn't work. I can see that
> in the latter case Excel calls my ConnectData() just as usual but
> almost immediately thereafter it calls DisconnectData() -- without any
> apparent reason. Even more surprizingly, it still calls RefreshData()
> for the topic it just disconnected from.
>
> The fact that =RTD() in the worksheet works makes me suspect that this
> is a beta2 bug, I hope this wasn't a conscious design decision in Excel
> 2007, so I can only hope it's going to be fixed in the final version.
>
> Regards,
> VZ
>