Restart BLE stack causes chip reset

[Massimo Pilia]

Hi everybody,

I'm trying to hide some characteristics till the user write the right value to a secure pin characteristic the devise exposes at the beginning. I already did it but, when the user disconnects his device and repeat the pairing procedure, then the hidden characteristics are shown twice and, if hi continues, thrice and so on. So, reading this post on the Nordic Developer Zone , I should disable the soft device, in order to remove the entire GATT database, and then enable it again. I'm trying to do this by calling the function services_destroy() in the BLE_GAP_EVT_DISCONNECTED of the on_ble_evt(ble_evt_t * p_ble_evt), but this causes a chip reset.

void services_destroy(void)
{
	uint32_t err_code;

	err_code = sd_softdevice_disable();
	if(err_code != NRF_SUCCESS)
	{
		UART_TxLogDebug(MODULE_NAME(BLE_CUSTOM),LOG_ERROR,FUNC,INFO_Y,2,
				UART_STRING("err_code = "), UART_UINT32(err_code, HEX));
	}
	APP_ERROR_CHECK(err_code);

	ble_stack_init();
}


static void on_ble_evt(ble_evt_t * p_ble_evt)
{
	uint32_t err_code;

	switch (p_ble_evt->header.evt_id)
	{
	case BLE_GAP_EVT_CONNECTED:
		UART_TxLogDebug(MODULE_NAME(BLE_CUSTOM),LOG_INFO,FUNC,INFO_Y,1,\
				UART_STRING("BLE_GAP_EVT_CONNECTED"));
		err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);
		APP_ERROR_CHECK(err_code);
		m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;

#ifdef INSERT_PIN_ENABLED
		ble_state = BSP_STATE_PAIRING;

		one_sec_timer_start();
		config_service_variable.security_pin.pin_timeout = TIME_OUT_PIN;
		config_service_variable.security_pin.pin_insertions = 0;
#else
		ble_state = BSP_STATE_READY;
#endif

#ifdef ADC_CUSTOM_ENABLED
		//Battery Level reading
		adc_enable();
#endif //ADC_CUSTOM_ENABLED 
		break;

	case BLE_GAP_EVT_DISCONNECTED:
		UART_TxLogDebug(MODULE_NAME(BLE_CUSTOM),LOG_INFO,FUNC,INFO_Y,1,\
				UART_STRING("BLE_GAP_EVT_DISCONNECTED"));

#ifdef HIDE_CHARACTERISTICS_BEFORE_PIN
		services_destroy();
		services_PIN_init(FALSE);
#endif //HIDE_CHARACTERISTICS_BEFORE_PIN
		m_conn_handle = BLE_CONN_HANDLE_INVALID;

#ifdef BLE_BEACON_ENABLED
		ble_state = BSP_STATE_BEACON;
#else
		ble_state = BSP_STATE_ADV;
#endif

#ifdef INSERT_PIN_ENABLED
		one_sec_timer_stop();
#endif

#ifndef BLE_BEACON_ENABLED
		application_ble_advertising_start();
#else
		beacon_advertising_start();
#endif
		break;

	default:
		// No implementation needed.
		break;
	}
}

Guessing the issue was caused by the wrong position of the calling of the sd_softdevice_disable() I tried to put it in the main function, but I got the same result!

What am I doing wrong? Any suggestion? Thanks in advance:

Massimo Pilia

[Petter Myhre]

You are only adding services aren't you? That shouldn't be a problem, the post you refer to are about removing services. Anyways, what error code does sd_softdevice_disable() return?

[Massimo Pilia]

Actually I do need to remove some characteristics when the user disconnects from the device and add them again only when the user provides a correct pin number in the unique visible characteristic. Debugging the code I discover that the problem is in the ble_stack_init() where, internally, the SOFTDEVICE_HANDLER_INIT(&clock_lf_cfg, NULL) return this error: NRF_ERROR_SVC_HANDLER_MISSING.

[Petter Myhre]

Do you mean softdevice_handler_init()? So 0x0001 is returned? Could you go inside it and see which function that returns NRF_ERROR_SVC_HANDLER_MISSING? What SoftDevice version are you using?

[Massimo Pilia]

Yes, softdevice_handler_init called inside the macro SOFTDEVICE_HANDLER_INIT. Anyway, I discovered the problem wasn't the handler. The proper error code was NRF_ERROR_SDM_INCORRECT_INTERRUPT_CONFIGURATION (0x1001) that comes up because I had set the adc IRQ priority level too high (0). To discover it I had to disable all the IRQs and than enable them once a time. Finally, when I founded the issue was caused by the adc module, I set its IRQ priority to APP_IRQ_PRIORITY_LOW (3) and everything starts to work fine!

[Petter Myhre]

Great! So is everything is okay now?