connection quick disconnect, error code BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED

[Not2Good Sir]

Hi All: I met a trouble， i don't slove it. i need help . sdk : nRF5_SDK_14.0.0 S132 hardware: nrf52832 base multitole dev.

nrf52832 as master to connect mobile by ble.
but the connection is always easy to to disconnect. error code is BLE_HCI_CONN_FAILED_TO_BE_ESTABLISHED (0x3E). 
i find slove in internet, i see some people say this is remote not response first 6 packet.and i capture it, 

airlog.zip

i don't know how to slove it. please help me.

[run_ar]

Does this happen all the time or only occationaly? If it happens occationally I doubt there is anything you can do about it. I.e. if there are any issues with the connection request you will not be able to establish a connection. If it happens always, you need to check that you are not using a whitelist with another device in it.

[Not2Good Sir]

Hi run_ar: Thanks for your reply. this occationaly happen. about 20%, i guess this maybe related to the connection parameters. What connection parameters on the use of connection any reference ? i use 7 7 0 10 now.

[run_ar]

Which softdevice revision are you using? And what phone are you connecting with?

The connection parameter does not matter. Looks like it is the connection request itself that is failing.

Anyway using 10 as connction supervision timeout might be a bit low. If it works with your use case I would at least double that.