BLE connection cannot established anymore after disconnect by peripherals itself several times

[kathyh]

Hi NXP team,

I am using SDK_2.x_QN9090D V2.6.5 for developing a BLE project. Currently, the UM040 EVK is programmed as a BLE peripheral, and multiple GAP connections can be established. Once the connections last a few minutes, I will use the Gap_Disconnect() function to disconnect it and allow more centrals to connect.

At the beginning, I establish four connections and disconnect them one by one after a few minutes, while keeping the scanning active. After disconnection, four connections will be established again within a few seconds. I repeat this loop indefinitely, disconnecting after a few minutes each time.

However, after a few iterations, I noticed a reduction in the successful establishment of connections. Initially, it reduces to three connections, and after a few more iterations, it further reduces to two connections.

May I know what caused this connection reduction? and How to solve it? Thank you very much.

Kathy

[Ricardo_Zamora]

Hello,

Hope you are doing well. Could you please clarify what EVK are you using?

Best Regards,

Ricardo

[kathyh]

Hi Ricardo,

Thanks for your reply. I am using customized EVK with QN9090 MCU. Do you know how to solve the issue?

Another, Do you know how to enable the BLE stack level logs? Thank you very much.

Best Regards,

kathy

[Ricardo_Zamora]

Hello Kathy,

Could you please tell us what SDK example are you using as a base? What modifications did you implement?

Is this behavior present when trying with our EVK? Could you try with the latest SDK?

For the debugging question, you would need to modify the APP_DBG_LVL of the SDK example to DBG_LEVEL_DEBUG or DBG_LEVEL_VERBOSE.

Regards,

Ricardo

[kathyh]

Hi Ricardo,

sorry for the late reply.

I am using the UWBIOT_SR040_v04.03.14_MCUx\uwbiot-top\demos\SR040\demo_nearby_interaction example as the base project. I have added a timer once connected to a peripheral. The timer is used to periodically disconnect by using the Gap_Disconnect() function.

Additionally, I have enabled logging, but there are no useful logs generated when the issue occurs.

Regards,

kathy

[Ricardo_Zamora]

Hello kathy,

As you are using an example that is not from the MCUXpresso SDK the support is limited.

I would recommend you contacting the person who provided that example.

Regards,

Ricardo

[kathyh]

Hi Ricardo,

Thank you for your clarification. May I know if there is any example in the MCUXpresso SDK that demonstrates similar functions for establishing multiple BLE connections? This would allow me to verify and facilitate debugging. Thank you very much.

Best Regards，

Kathy

[Ricardo_Zamora]

Hello Kathy,

You could check the Wireless UART example. More information about the usage of this SDK example can be found on the "Bluetooth Low Energy Demo Applications User's Guide.pdf". (Path: SDK_QN9090DK6.zip\docs\wireless\Bluetooth).

Hope this helps.

Regards,

Ricardo