BtCoreIf.dll

[ssk]

The instructions for using Bluetooth with Broadcom Bluetooth enabled PDAs is this:

If your device uses the Broadcom Bluetooth driver, install the LabVIEW WIDCOMM Bluetooth driver by manually copying LVBtw.dll from the labview\PDA\Utilities\Bluetooth directory to the Windows directory. Do not run Setup.exe and do not copy BtCoreIf.dll or BtSdkCE30.dll if they already exist on the device.

I have two old Windows mobile 2003 PDA that will not run if I follow the instructions above to the letter. They will however work if I overwrite the existing BtCoreIf.dll with the later one provided with LabVIEW.

My question is this: What is the effect of overwriting the old file and why does NI stipulate that it must not be overwritten?

Thanks

ssk

[Jeremy_T]

Hi ssk

I hope you're well. I've been looking into this to try and find out the exact purpose of all three of the DLLs and hence to work out why two of them should not be copied over. I would expect that the BtCoreIf and BtSdkCE30 DLLs may be core DLLs for Bluetooth and the Bluetooth Software Development Kit (SDK) respectively. There is a possibility that the old version of BtCoreIf.dll corresponded to an older version of LabVIEW and by overwriting it, you may have then matched it to the version you are running. I cannot be certain of this though, so I am getting in touch with the product specialists, who may be able to advise on the reasons why this is the case.

When the PDAs were not running, did you get any specific error messages?

I'll update you on my progress with finding out more about these DLLs and will be in touch with you again soon.

Kind Regards

[ssk]

Hi Jeremy,

Thanks for your reply. I was not trapping any error messages but could get them if that would be of any help.

Thanks

ssk

[Jeremy_T]

Hi ssk

Thanks for getting back to me. Any error codes or messages you could let me know about would be really handy.

Thanks

[Jeremy_T · Accepted solution]

Hi ssk

I've found out some more information that I think will be useful for you. The DLL that you overwrote is, in fact, the Bluetooth Connection Wizard. It would seem that the reason the DLL should not be overwritten, is because generally the DLL that exists on the device will be the one corresponding to the current version of the associated driver. However in cases like yours, where the device is not working, it probably means that the DLL does not match the driver version available. By overwriting the existing DLL with the one provided alongside the  LabVIEW WIDCOMM driver, it is most likely that the DLL and driver versions were then compatible.

In general, the reason why NI recommend that the DLL should not be overwritten is because if the drivers are working anyway there is no need to replace the driver components (such as the Bluetooth Connection Wizard). Instead what we want to do is simply copy over the LVBtw DLL, which provides the 'hooks' for LabVIEW to communicate via Bluetooth using the current available driver. Since in your case the drivers were not working anyway, there should be no ill-effects from replacing the DLL in the described manner.

I hope this helps!

Kind Regards

[ssk]

Hi Jeremy,

That makes perfect sense, I tried this on several PDAs and some (that were running a different Windows Mobile to the one that I copied the DLLs from), started to display Bluetooth errors. The only one that did not display an error was the one that did not work with my LabVIEW application. This one then worked fine with the latest DLLs.

So I guess if it aint broke, don't fix it. If it is broke, fix it (overwrite)!!

I have only seen 3 Windows Mobile 2003 devices with this problem, most of the other WM2003 devices work OK with their native DLLs.

Thanks.

[Jeremy_T]

Hi ssk

You're welcome. Good luck with the rest of your project!

Kind Regards