Can't open a dll on the PDA when using pointers !

[StHommes]

Hi,

im using an HP Ipaq Pocket PC (Windows CE 4.21) and LV 8.20. I'm opening dlls on the PDA. Everything works fine, but if i open a dll which uses pointers, it doesn't work.

For example, if i have function like this:

int LIBFUNC T4Init(LPCTSTR Port); or

LPCTSTR LIBFUNC T4FindComPort (void);

Normally, the proper LabVIEW datatype for LPCTSTR is C-String. But it doesn't fit.

Any ideas?

Thanks.

[Wolfgang_Z.]

Hello StHommes!

Actually it should work.
There are some specials with dll calls on PDA.
http://digital.ni.com/public.nsf/websearch/517300B49212795986256DDD00623FEE?OpenDocument

Further you should read this KnowledgeBase.
There you can find information how to pass Null Pointer to a DLL.
http://digital.ni.com/public.nsf/allkb/B86515E47C330E3086256E7E005DD109

Did you choose the right Calling Convention?
Is the dll working in LabVIEW (not LabVIEW PDA)?
Which error message did you get?
Could you post the dll with source code here?

Thanks and regards,

WolfgangZ

[miko]

LPCTSTR on Pocket PC is a wide character string pointer (WCHAR*). If you want to pass C strings using the call library node, you have to change your function prototype to use "char*" instead of LPCTSTR because LabVIEW PDA passes the strings as multibyte strings.