Specific Android tablet model isn't able to reliably connect

RE: Specific Android tablet model isn't able to reliably connect

FlsZen — Tue, 23 Jan 2024 23:56:46 GMT

Thanks! Setting `CONFIG_BT_AUTO_PHY_UPDATE=n` resolves the issue when this M10 is connecting to it and I can now re-enable the 2Mbps PHY option which was my previous workaround.

RE: Specific Android tablet model isn't able to reliably connect

Hung Bui — Tue, 23 Jan 2024 08:25:52 GMT

Hi James,

It's most likely because of the CONFIG_BT_AUTO_PHY_UPDATE. It's by default =y.
You can turn it off if you don't plan to let the peripheral to request PHY update.
If you want the peripheral to request PHY update but have more control over it, you can use CONFIG_BT_USER_PHY_UPDATE=y then call bt_conn_le_phy_update() in your application.
Please let us know if this doesn't fix the problem for you.

RE: Specific Android tablet model isn't able to reliably connect

FlsZen — Mon, 22 Jan 2024 21:34:27 GMT

Hi,

I don't believe I'm calling any code that would initiate a PHY update from my code on the nRF52, is there something that would be on by default that I may need to turn off?

To eliminate variables from my concern here, I have built and flashed the peripheral_lbs sample to my nRF52-DK. My other devices connect and interact fine with the sample app, but this M10 tablet continues to time out in the same place while connecting. The nRF Connect log is identical in that it disconnects just under 5 seconds after logging "PHY updated (TX: LE 2M, RX: LE 2M)". I can provide logs from the running peripheral_lbs sample code if needed.

RE: Specific Android tablet model isn't able to reliably connect

Hung Bui — Mon, 22 Jan 2024 12:44:22 GMT

Hi James,

Reason 0x2A = DIFFERENT_TRANSACTION_COLLISION. This can happen when the central send a PHY update and connection parameter update next to each other (collision).
The PHY update actually requested by the nR52. My suggestion is to try putting a delay in the request in the code so that it doesn't happen at the same time as with the connection parameter update from the central.