nRF52832 connection problem with some android device

[asdf]

Hi, I'm using nRF52832 with sdk 13.1.0(softdevice 4.0.2). I had trouble to connect nRF52832 in some android smart device.When I restart Bluetooth,Sometimes there are problems connecting(GATT ERROR 133).Then never connected to the device unless I restart the Bluetooth or lock screen.(Only some devices).

[endnode]

This question should be renamed to "some android devices have faulty BT controlers/stacks and so they are failing in various situations regardless of what BLE controller is on the other side" (end then you can close it;).

[Hung Bui]

Could you provide some more information about your Android device ? We have seen error 133 quite often in the past but didn't have a clear explanation why it happens. You can try to add some delay before you do anything after connection established. As you can read about it here and here.

Also, please try using the nRFConnect app for testing.

[asdf]

I try to use the nRFConnect app for testing.Unfortunately, it also does not work.This is some log in the nrfConnect app:

V	11:02:01.524	Connecting to DF:85:27:EB:8A:C9...
D	11:02:01.524	gatt = device.connectGatt(autoConnect = false, TRANSPORT_LE)
D	11:02:31.554	[Callback] Connection state changed with status: 133 and new state: DISCONNECTED (0)
E	11:02:31.556	Error 133 (0x85): GATT ERROR
I	11:02:31.556	Disconnected
D	11:02:34.154	gatt.close()
D	11:02:34.155	wait(200)
V	11:02:01.524	Connecting to DF:85:27:EB:8A:C9...

... And if i can connect the device this time, I can pull my device a long way to disconnect the connection, and then close, it can always reconnect, but I have the chance to restart the Bluetooth will not connect the device.

But i find the only one app can connect the device.(BLE Scanner(bluepixeltech) can). My device is Sony xperia Z4.(Update the system to android6.0) Sony xperia Z5 is OK.

[asdf]

Your sharing is useful。Thank you very much.