K8055 dllImport c# Problem

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1

I have been playing with the code and most of it works.

What is really strange is that some of the functions within the K8055D_C.dll work correctly BUT others like WriteAllDigital always breaks in to the debugger with

System.EntryPointNotFoundException
Unable to find an entry point named ‘WriteAllDigital’ in DLL ‘K8055D_C.DLL’

I can connect to the device, I can SETALLDIGITAL and CLEARALLDIGITAL but the rest I always get this error.

I have downloaded the latest DLL’s, I have tried the old ones, the new ones, I have copied the files to the c:\windows\System and c:\windows\system32 and every sub directory of my project. But it appears to make no difference.

Any ideas? It maybe a VS2005 C# feature I am missing, or have misunderstood.

I have even created a managed code DLL and used dllImport in this DLL to be sure that it was not an unmananged code problem, still with no luck.

Thanks

Chris

2

[quote]System.EntryPointNotFoundException
Unable to find an entry point named ‘WriteAllDigital’ in DLL ‘K8055D_C.DLL’[/quote]

That’s because there is no function ‘WriteAllDigital’ in K8055D_C.dll. If you look at the exports inside the dll, you’ll notice that all of them have name mangling:

So no functions you’d ever have imported would have worked (or even been found), so I don’t understand how any of your functions can work correctly…

It would be better for you to use K8055D.dll which exports all functions without name mangling.

Good luck!

3

Thank you for the reply,

I completely agree, I was on the assumption (wrongly it would appear) that I required the K8055D_C.dll for C# applications so I used dllImport[“K8055D_C.dll”].

I also don’t understand how this could work for some functions, this is what has caused me to pull a large portion of my hair out, it made no sense.

Name Mangling - Does this render the exports unusable?

Chris

4

I agree that it’s a bit confusing, i had to take a closer look too :-/

If you really want to use the functions in K8055D_C.dll you just need to use the mangled names:

[DllImport("K8055D_C.dll", EntryPoint = "_CloseDevice@0")]
public static extern void CloseDevice();

Enjoy!

5

Thanks again

I assume there is some mileage in doing this or is the standard K8055D.dll OK to use? I guess using the new method it is saving a split second hop from 1 dll to the other?

Great little project board though.

Cheers

Chris

6

I don’t think the dlls use each other :slight_smile: I’m guessing the only reason why there are two dlls is because one is included with a .lib (static linking) for borland C++ builder (different format than microsoft).

Choose whichever one you want, they should be exactly the same. The only difference for you in C# are the exported names. Personally i’d use K8055D.dll for its simplicity.