stephen trowbridge

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8 years, 10 months ago.

BLE stability issue

Hi

We've been using your nRF51822 mbed implementation since last year and it always worked great! Thanks a lot!

Now we had to update to Softdevice 8 and we are facing serious stability issues. The connection keeps breaking after 30min - 1h. I've checked it with a sniffer. Our Periphery device just stops answering to a stable connection but it does not dissconnect (no dissconnection callback and no start of advertising). See the sniffer log here:

/media/uploads/strowbridge/ble_stabilityissue.png

No to be sure it's not a App problem, if've removed everything appart from the BLE code. And it still crashes. To be even more safe, I did Flash it to the nrf dongle from Nordic. And it still crashed. Here is the very minimal code:

extracted code

PainGuard::PainGuard()
{
	_pBle = new BLEDevice();
	_pBle->init();	
	
																			
	_pDeviceInformationService = new DeviceInformationService(*_pBle,
				"Manufacturer", //manufacturersName
			        "Gadget", //modelNumber
				"00000000", //serialNumber
				"1", //hardwareRevision
				STR_FW_VERSION, //firmwareRevision
				"0.1"); //softwareRevision			
}

void PainGuard::init(void)
{
	_pTicker = new Ticker();
	
	_pBle->gap().onDisconnection(disconnectionCallback);
	_pBle->gap().onConnection(connectionCallback);
	_pBle->gattServer().onDataSent(onDataSent);
	_pBle->onDataWritten(onDataWritten);

	// setup advertising and prefered connection parameters
	_pBle->accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE);
	_pBle->setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
	_pBle->setAdvertisingInterval(ADVERTISING_INTERVAL_MS);
	_pBle->setDeviceName(reinterpret_cast<const uint8_t*>("Gadget"));
	_pBle->gap().accumulateScanResponse(GapAdvertisingData::COMPLETE_LOCAL_NAME, reinterpret_cast<const uint8_t*>("LiquiGadget"), 6);
	
	_pBle->gap().setPreferredConnectionParams(&_connectionParamsFast);
	_pTicker->attach_us(&PainGuard::periodicCallback, MEASUREMENT_INTERVAL_MS*1000);
		
	_pBle->startAdvertising();     
  
}

void PainGuard::onDataSent(unsigned count) // called after notifications have been sent
{
  _pServiceDataHandler->notificationHandler(ServiceDataHandler::CONTEXT_CB);
}

void PainGuard::disconnectionCallback(const Gap::DisconnectionCallbackParams_t *params)
{
  _pBle->startAdvertising();
}

void PainGuard::connectionCallback(const Gap::ConnectionCallbackParams_t* param)
{
	Gap::Handle_t gap_handle = param->handle;
  _pBle->gap().updateConnectionParams(gap_handle, &_connectionParamsFast);
}
/**
 * Runs once a second in interrupt context triggered by the 'ticker';
 */

void PainGuard::periodicCallback()
{
	_MeasurementPending = true;
}

void PainGuard::process()
{
	_pBle->waitForEvent();
}

Now I'm wondering whether you also face these problems? As mentioned, it only happens after >30min. Or is there anything I'm doing terribly wrong?

Thanks for your help! Stephen

Question relating to:

Last updated: 14 Sep 2016
Nordic stack and drivers for the mbed BLE API

This sounds very similar to what I'm experiencing with some nRF51-DK prototypes. Did you get anywhere in solving this?

Anyone else have ideas?

posted by CJ Shaw 05 Jul 2016
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