BLE connection problem

RE: BLE connection problem

Sigurd — Mon, 21 Aug 2017 13:10:20 GMT

Hi, take a look at this post for how to debug.

RE: BLE connection problem

DragonAnger — Sun, 20 Aug 2017 23:56:29 GMT

I found out that it's not android side problem. Error occurs at BLE module. but it's not the error in nrf_error.h. Something else. But I don't know error code because SEGGER_RTT_printf() function is not working. only SEGGER_RTT_WriteString() works. So, I checked one by one using SEGGER_RTT_WriteString() And I think this error can be related with UART. How can I debug this? Thanks for reading my question.

RE: BLE connection problem

DragonAnger — Wed, 16 Aug 2017 09:19:26 GMT

Connection is like this, My custom board-(UART serial)-> Motherboard-(BLE)->Android When I tested with PC terminal with default setting, I don't get the Device is not supported message but cannot 100% sure.

RE: BLE connection problem

Sigurd — Wed, 16 Aug 2017 07:44:52 GMT

Is this a custom board or the nRF51-DK ? On the nRF51-DK, the on-board Segger J-link programmer that have the Virtual COM port via UART, uses pin 9 and 11. So if you are using the DK you won't be able to send and receive data from the PC terminal if you change the pins to 5 and 6.

So if you use the default pin numbers(11 and 9), then you don't get the Device is not supported message ?

RE: BLE connection problem

DragonAnger — Wed, 16 Aug 2017 06:15:57 GMT

Thanks for your answer! BLE device is not paired or bonded. And If device is paired or bonded, I need software solution. Because it didn't happen always. And I tried to your code, It didn't work. I changed RX_PIN_NUMBER and TX_PIN_NUMBER to 5 and 6 (default number is 11, 9) to connect UART with my board. Is that something to do with? Because this problem didn't happen before that. Again, Thank you for answering my question!

RE: BLE connection problem

Sigurd — Mon, 14 Aug 2017 09:22:52 GMT

Hi,

Did you go into Bluetooth settings on your phone, and removed the device form the list of paired/bonded the devices? Also try to restart the phone.

On the nRF51, you could try to enable the Service Changed characteristic so that changes in the application are indicated to the phone. Set IS_SRVC_CHANGED_CHARACT_PRESENT to 1.

Code snippet(SDK12.3):

// Initialize the SoftDevice handler module.
SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL);

ble_enable_params_t ble_enable_params;
err_code = softdevice_enable_get_default_config(CENTRAL_LINK_COUNT,
                                                PERIPHERAL_LINK_COUNT,
                                                &ble_enable_params);
APP_ERROR_CHECK(err_code);

ble_enable_params.gatts_enable_params.service_changed = IS_SRVC_CHANGED_CHARACT_PRESENT;

RE: BLE connection problem

DragonAnger — Mon, 14 Aug 2017 06:42:16 GMT

Hi Sigurd,

I checked the thread.

I suspected that android has cached previous services from the device.

So, I tried this but didn't work.

Is there other way to clear service cache or anyone solve this problem?

RE: BLE connection problem

DragonAnger — Fri, 11 Aug 2017 08:36:14 GMT

Thank you for your answer Sigurd! I'll check it and let you know.

RE: BLE connection problem

DragonAnger — Fri, 11 Aug 2017 08:34:43 GMT

I want to find way without those devices right now. But Thank you for your answer!

RE: BLE connection problem

Sigurd — Fri, 11 Aug 2017 08:34:37 GMT

Hi,

A quote from this thread on a similar issue (Device is not supported message).

I suspect the android device is still not making full device discovery for the services and still has an old gatt table with services that you previously bonded with. Try to go into Bluetooth settings on your phone, forget all bluetooth services/devices that you have listed there and perhaps disable Bluetooth and enable it again. Then try to connect with the nRF52 device.

RE: BLE connection problem

endnode — Fri, 11 Aug 2017 08:25:25 GMT

Mobile phone is kind of black box when it comes to BLE so all logging and indications you get are indirect. If you really want to know which peer disconnected, when and probably why you need RF trace from BLE sniffer or similar network analyzer.