File-Downloader fails to start on Samsung A8 that connects in Phy1M mode to a device based on nRF51* chipset

[ksidirop-laerdal]

Even though we had success making Samsung A8 work in terms of uploading files/firmwares to our devices via:

Phy1M mode + initial-mtu-size=23 + window-size=1

We can't repeat this on the file-downloader using:

Phy1M mode + initial-mtu-size=<23 or any value all the way up to 100> (window-size is not supported in the file-downloader)

We get an error instead:

Transaction 0 timed out without receiving a response

The file-downloader works great using the same code on any other Android device even in Phy1M if we use initial-mtu-size >= 30. It's only Samsung A8 that suffers from this shortcoming.

( We suspect it might have to do with the fact that we can't set the window-size like we do with the file-uploader - but that's just a blind guess )

Any ideas as to what we might be doing wrong are welcome. Code sample:

        _transport = new McuMgrBleTransport(_context, _bluetoothDevice);
        if (initialMtuSize > 0)
        {
            _transport.setInitialMtu(initialMtuSize);
        }

        _transport.requestConnPriority(ConnectionPriorityRequest.CONNECTION_PRIORITY_HIGH);

       _fileSystemManager = new FsManager(_transport); 

       _downloadingController = _fileSystemManager.fileDownload(_remoteFilePathSanitized, new FileDownloaderCallbackProxy());

[LightWeek]

I am encountering the same error on a Pixel 3a running Android 12 when attempting to download a file from our nRF52 device. The error consistently reproduces in the nRF Device Manager app and in our app using McuMgrBleTransport + FsManager (code as simple as in the original post above).

However, downloading the same file from the same nRF52 device works as expected on other test phones (ranging from Android 12 to Android 15 and iOS).

[LightWeek]

@ksidirop-laerdal Have you found any solution to this issue? @philips77 Do you know possible cause or solution? Should I provide any more information or logs?

BTW. For some reason logger app is not available on Google Play and one installed from APK doesn't connect with Device Manager app.

[philips77]

Oh, great catch. I need to update the target SDK in the app to make it available again.

[ksidirop-laerdal]

@ksidirop-laerdal Have you found any solution to this issue?

Still waiting on more info on this too. Currently it doesn't bother me too much but it's somewhat concerning in general.