Why is BLE(nrf52810) disconnected automatically after connecting to nrf connect tool?

[duxinglang]

I have a project to use NRF52810 to connect the App. When testing it, I found that when it was successfully connected to the NRF Connect tool, it would automatically disconnect after about 30 seconds. Through the log, we can find that it was received successively in the ble_evt_handler function  

BLE_GAP_EVT_CONN_PARAM_UPDATE and BLE_GAP_EVT_DISCONNECTED messages, and disconnect reason returns 0x22, which is BLE_HCI_STATUS_CODE_LMP_RESPONSE_TIMEOUT,  Why does this happen?  

[ovrebekk]

Hi 

Are you using one of the standard examples in the SDK to do this test? 
If yes, which one?

Are you trying this on some kind of Nordic DK, or on custom hardware?

Best regards
Torbjørn

[duxinglang]

HI

yes, i using the examples: examples\ble_peripheral\ble_app_template in the SDK16.0.on custom hardware.

thanks!

[ovrebekk]

Hi 

Are you able to capture the connection attempt using a BLE sniffer, such as the nRF Sniffer?

Are you using external or internal 32kHz LF source?

Could you share the schematic of the board with me?
I can make the case private if you want, in case you don't want to share the design in public. 

Best regards
Torbjørn

[duxinglang]

I found that my code did not process the message BLE_GAP_EVT_PHY_UPDATE_REQUEST, which caused the disconnection. After adding, it will be normal. Thank you for your reply.