[TEST REQUEST] Windows Bluetooth LE build

Lubomir I. Ivanov neolit123 at gmail.com
Mon Oct 1 19:27:47 PDT 2018

On Mon, 1 Oct 2018 at 16:17, Dirk Hohndel <dirk at hohndel.org> wrote:
> > On Sep 30, 2018, at 6:40 PM, Lubomir I. Ivanov <neolit123 at gmail.com> wrote:
> >>
> >> Rebooted. Nothing else running, just the cmd.exe
> >>
> >> Same output - semaphore timeout period has expired.
> >>
> >

did some more testing here.

my phone's BT is off all the time, i don't anything to use it with.
i'm able to reproduce this error if i pair and connect my phone using
NRF Connect with the DC, and then try to connect and write a
descriptor using the qt-bt-discovery.exe app.
to get out of this scenario i disconnect from the NRF Connect app.
at this point qt-bt-discovery.exe writes the descriptor correctly.

but this is not consistent - it can lead into all sorts of weird
conditions, like:
- writing the descriptor from the .EXE app disconnects the phone.
- if the phone is disconnected after that, it can no longer connect to
the device and the phone BT has to be turned off/on.
- if the phone "takes ownership" of the device, the Windows BT has to
be turned off/on, but then it decides to forget the the DC 50% of the
- rediscovering the device in Windows might fail to pair or the
discovery process even crashes - OS restart is required.

this proves to me that there are ownership issues here, but also that
the whole process is quite unreliable.

so if another device other than the Windows laptop is connected to the
DC, writing to a service will simply fail with the semaphore error and
there would be no other indication.
could you try turning all suspect local devices off for such a test?

...but something else here, the Qt code is doing everything correctly
and i cannot blame it, at this point.
for now i can only blame Windows' BT support and BT as a whole.

> Also, how do I quit the program? Ctrl-C doesn't appear to work. All I can figure out is kill the cmd.exe.
> That doesn't seem like the right way to do this :-)

i have updated the test app to now properly exit on ctrl+c:


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