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VC6 Simple Example for U12 - Windows

A simple example of a Visual C (VC6) console program that calls AISample from the LabJack U12 Legacy DLL. 1/30/2002, 107 KB
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I'm trying to create a dll for EDigitalIn function, but I can't do it with my little knowledge of programming or the examples I found online, I always get the error "unresolved external symbol [email protected]". Could you guide me on how to create it?

Thank you so much.

The EDigitalIn function is provided in the U12 driver (ljackuw.dll) which we provide.  You do not need to write the EDigitalIn function and create the dll for it. Use the U12 installer to install our software before writing and running your code:


In Visual Studios C/C++, you can link to the driver by adding the ljackuw.lib file to you project. "#include" the dll's header file, ljackuw.h, in your code for the function declarations. The header file also has function documentation. The example shows this but folder paths may need to be corrected for your system. The .lib and .h files are in the installed "LabJackU12Legacy\drivers" folder. On 32-bit Windows this is in your "C:\Program Files\" folder and on 64-bit Windows it is in the "C:\Program Files (x86)\" folder.

For the U12 driver's programming reference, take a look at this section of the User's Guide:


If for some reason you need to create a dll to use our dll (?), here's a MSDN walkthrough on creating dlls: