Using library call nodes

[WKOptro]

I have attached a simple VI which uses a Call Library Node to open a serial communication port.  When I run this VI, LabView crashes.  I have attached the VI and the dll.  I have verified that the calling parameters are correct for the function.  Can anyone help me understand what is going on or how I can execute this or other CLN's using the same .dll?

The source for the .dll is available at the SeaLevel System's website.  The card it is interfacing with is a Route56 PCI CCA P/N 5101.

Thank you. 

[nate]

I have had this issue ocurr before when I did not pass the correct parameters to the Call Library Function, or I did not specify the correct calling convention.

What does the prototype for the function look like?

[WKOptro]

unsigned long SEAMAC_PortOpen(unsigned short int DriverType, unsigned short int PortNumber, unsigned long *hDevice);

[Wiebe@CARYA]

Try it with the calling convention set to stdcall. That convention is normally used on windows.

Regards,

Wiebe.

[WKOptro]

Thank you for the suggestion.  The VI runs without crashing now.  Can anyone expain why?

[GuenterMueller]

You must use the correct calling convention to prevent stack violation.

Details can be taken e.g. from here.

Regards, Guenter

[Wiebe@CARYA]

To apply this (haven't actually read the link) to your application:


The main difference is that order the inputs are passed is reversed. So in your, the first parameter (a enumerated value) will be used as a pointer (the last input). When the dll code will try to write it's data to this pointer, it will crash.


Regards,


Wiebe.