[TEST REQUEST] Windows Bluetooth LE build

Lubomir I. Ivanov neolit123 at gmail.com
Sun Sep 30 18:09:44 PDT 2018

On Mon, 1 Oct 2018 at 03:38, Dirk Hohndel <dirk at hohndel.org> wrote:
> The crazy thing is that this morning I successfully downloaded from this very dive computer. And I have not the faintest clue what I have changed. I have gone back to the same binary that I am pretty sure is the one that I used… doesn’t work.

has the machine been restarted since the morning?

> First we have this:
> qt.bluetooth.windows: Unable to get value for characteristic "{27b7570b-359e-45a3-91bb-cf7e70049bd2}" of the service "{fe25c237-0ece-443c-b0aa-e02033e7029d}" : "No attribute found within the given attribute handle range."

this can happen in a case where a characteristic is WriteOnly.
the Qt stack tries to pre-populate values of a all characteristics in
a map when it discovers them, but it would still complain if it cannot
obtain a value of a WriteOnly char.

this can be improved in the Qt stack, but for now we can ignore it as
it's not critical.

> And then the whole “semaphore timeout period has expired” thing…

this comes directly from the Windows GATT backend for writing descriptors.

ERROR_SEM_TIMEOUT can happen in a case where the service path is
already opened in another process and this process has acquired an
exclusive lock on the path.
for instance, this can happen if i start BLE Explorer, connect to the
same device and start changing values in a service. then run the
qt-bt-discovery test app and try to do the same while both apps are


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