Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

Simonr — Mon, 14 Oct 2024 07:31:07 GMT

After a quick chat with one of our Android developers there is nothing we can do in the Android BLE library to ignore this auto PHY updates, as the Android stack will adhere to these if 2MBPS is supported.

Best regards,

Simon

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

tellg — Tue, 08 Oct 2024 13:02:04 GMT

That doesn't work, as the peripheral sets it back to 2MBPS, due to CONFIG_BT_AUTO_PHY_UPDATE as default,

which is 'y'

Sniffer log attached devzone.nordicsemi.com/.../try_2D00_1mbit_2D00_phy_2D00_from_2D00_nrfconnect.pcapng

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

Simonr — Tue, 08 Oct 2024 12:42:51 GMT

Ah, of course. Sorry about that. The preferred PHY is indeed only a suggestion and will be negotiated upon a connection. AFAIK there is no way to hard set the used PHY to automatically set o 1MBPS, but you can change the PHY manually after connecting to the device by going to the connection settings and changing it from there.

Best regards,

Simon

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

tellg — Mon, 07 Oct 2024 09:07:46 GMT

That does not help, as we anyhow end up in 2MBPS as soon as connection is done

I also tried this macro, but still end up in 2MBPS devzone.nordicsemi.com/.../SetPreferredPhy_5F00_1M.xml

nRFConnect log: devzone.nordicsemi.com/.../3051.Log_5F00_2024_2D00_10_2D00_07_5F00_11_5F00_14_5F00_25.txt

Seems like setPreferredPhy is just a recommendation, and depends on local and remote controllers behaviour

https://developer.android.com/reference/android/bluetooth/BluetoothGatt#setPreferredPhy(int,%20int,%20int)

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

Simonr — Mon, 07 Oct 2024 09:02:49 GMT

At least in the nRF Connect for Android app you can set the supported PHYs in the settings of the app (Settings -> Scanner -> Physical layer) to 1MBPS if you'd like.

Best regards,

Simon

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

tellg — Fri, 04 Oct 2024 12:07:10 GMT

We have seen that it helps setting CONFIG_BT_AUTO_PHY_UPDATE=n on the peripheral, and setting client side mcumgr initial mtu setting to 23

ref https://github.com/search?q=repo%3ANordicSemiconductor%2FAndroid-nRF-Connect-Device-Manager%20initialmtu&type=code

Downside is that devices already out in the field have CONFIG_BT_AUTO_PHY_UPDATE as default, which is 'y'

Is it possible from mcumgr android library to force using 1 Mbit phy when the device is SM-X200 (Galaxy tab A8)?

If so, then maybe also do this in the other libraries for SM-X200 (https://github.com/NordicSemiconductor/Android-BLE-Library and https://github.com/NordicSemiconductor/Android-DFU-Library)

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

Simonr — Fri, 04 Oct 2024 11:40:09 GMT

In 2022, we found an issue in the Samsung A8 series Bluetooth capabilities, where it apparently tries to send packets with longer payloads than what has been negotiated, which caused these issues to occur. It has been reported to Samsung, but I do not have a status beyond that I'm afraid. There is nothing to be done from the nRF side of the application to remedy this I'm afraid.

Best regards,

Simon

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

tellg — Fri, 04 Oct 2024 07:48:23 GMT

Another capture from the A8, this time using the nRFConnect Device Manager app to try to perform a OTA DFU.

Firmware is this time the smp_svr example running on nRF52840dk , ncs 2.6.1

devzone.nordicsemi.com/.../samsungA8_5F00_nrfConnect_5F00_Device_5F00_Manager_5F00_smp_5F00_svr_5F00_example_5F00_nRF52840dk.pcapng

Also on this capture we see a burst of "Central_0x0b3c1c55 Peripheral_0x0b3c1c55 ATT 37 Sent Read By Group Type Request, Primary Service, Handles: 0x0001..0xffff"

Details of Galaxy Tab 8:

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

tellg — Fri, 04 Oct 2024 07:13:09 GMT

Another capture from the A8, this time using the nRFConnect Device Manager app to try to perform a OTA DFU

devzone.nordicsemi.com/.../samsungA8_5F00_nrfConnect_5F00_Device_5F00_Manager.pcapng

RE: Galaxy Tab A8 fails to connect properly, while Galaxy Phone S10 works fine

bearsh — Fri, 04 Oct 2024 07:03:05 GMT

As it also affects me, I did also capture the communication

devzone.nordicsemi.com/.../nordic_2D00_sdk_2D00_2.6.1_5F00_samsung_2D00_SM_2D00_X200.pcapng.gz