/// <summary>
        /// Invoked once the user has selected the device to connect to.
        /// Once the user has selected the device,
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private async void ConnectButton_Click(object sender, RoutedEventArgs e)
        {
            // Make sure user has selected a device first
            if (resultsListView.SelectedItem != null)
            {
                rootPage.NotifyUser("Connecting to remote device. Please wait...", NotifyType.StatusMessage);
            }
            else
            {
                rootPage.NotifyUser("Please select an item to connect to", NotifyType.ErrorMessage);
                return;
            }

            RfcommChatDeviceDisplay deviceInfoDisp = resultsListView.SelectedItem as RfcommChatDeviceDisplay;

            // Perform device access checks before trying to get the device.
            // First, we check if consent has been explicitly denied by the user.
            DeviceAccessStatus accessStatus = DeviceAccessInformation.CreateFromId(deviceInfoDisp.Id).CurrentStatus;

            if (accessStatus == DeviceAccessStatus.DeniedByUser)
            {
                rootPage.NotifyUser("This app does not have access to connect to the remote device (please grant access in Settings > Privacy > Other Devices", NotifyType.ErrorMessage);
                return;
            }

            // If not, try to get the Bluetooth device
            try
            {
                bluetoothDevice = await BluetoothDevice.FromIdAsync(deviceInfoDisp.Id);
            }
            catch (Exception ex)
            {
                rootPage.NotifyUser(ex.Message, NotifyType.ErrorMessage);
                return;
            }

            // If we were unable to get a valid Bluetooth device object,
            // it's most likely because the user has specified that all unpaired devices
            // should not be interacted with.
            if (bluetoothDevice == null)
            {
                rootPage.NotifyUser("Bluetooth Device returned null. Access Status = " + accessStatus.ToString(), NotifyType.ErrorMessage);
            }

            // This should return a list of uncached Bluetooth services (so if the server was not active when paired, it will still be detected by this call
            var rfcommServices = await bluetoothDevice.GetRfcommServicesForIdAsync(
                RfcommServiceId.FromUuid(Constants.RfcommChatServiceUuid), BluetoothCacheMode.Uncached);

            if (rfcommServices.Services.Count > 0)
            {
                chatService = rfcommServices.Services[0];
            }
            else
            {
                rootPage.NotifyUser(
                    "Could not discover the chat service on the remote device",
                    NotifyType.StatusMessage);
                return;
            }

            // Do various checks of the SDP record to make sure you are talking to a device that actually supports the Bluetooth Rfcomm Chat Service
            var attributes = await chatService.GetSdpRawAttributesAsync();

            if (!attributes.ContainsKey(Constants.SdpServiceNameAttributeId))
            {
                rootPage.NotifyUser(
                    "The Chat service is not advertising the Service Name attribute (attribute id=0x100). " +
                    "Please verify that you are running the BluetoothRfcommChat server.",
                    NotifyType.ErrorMessage);
                RunButton.IsEnabled = true;
                return;
            }

            var attributeReader = DataReader.FromBuffer(attributes[Constants.SdpServiceNameAttributeId]);
            var attributeType   = attributeReader.ReadByte();

            if (attributeType != Constants.SdpServiceNameAttributeType)
            {
                rootPage.NotifyUser(
                    "The Chat service is using an unexpected format for the Service Name attribute. " +
                    "Please verify that you are running the BluetoothRfcommChat server.",
                    NotifyType.ErrorMessage);
                RunButton.IsEnabled = true;
                return;
            }

            var serviceNameLength = attributeReader.ReadByte();

            // The Service Name attribute requires UTF-8 encoding.
            attributeReader.UnicodeEncoding = UnicodeEncoding.Utf8;

            deviceWatcher.Stop();

            lock (this)
            {
                chatSocket = new StreamSocket();
            }
            try
            {
                await chatSocket.ConnectAsync(chatService.ConnectionHostName, chatService.ConnectionServiceName);

                SetChatUI(attributeReader.ReadString(serviceNameLength), bluetoothDevice.Name);
                chatWriter = new DataWriter(chatSocket.OutputStream);

                DataReader chatReader = new DataReader(chatSocket.InputStream);
                ReceiveStringLoop(chatReader);
            }
            catch (Exception ex)
            {
                switch ((uint)ex.HResult)
                {
                case (0x80070490):     // ERROR_ELEMENT_NOT_FOUND
                    rootPage.NotifyUser("Please verify that you are running the BluetoothRfcommChat server.", NotifyType.ErrorMessage);
                    RunButton.IsEnabled = true;
                    break;

                default:
                    throw;
                }
            }
        }
Exemple #2
0
        private async void Connect(DeviceInformation devInfo)
        {
            // Perform device access checks before trying to get the device.
            // First, we check if consent has been explicitly denied by the user.
            DeviceAccessStatus accessStatus = DeviceAccessInformation.CreateFromId(devInfo.Id).CurrentStatus;

            if (accessStatus != DeviceAccessStatus.Allowed)
            {
                System.Diagnostics.Debug.WriteLine("Access State: " + accessStatus);
                System.Diagnostics.Debug.WriteLine("This app does not have access to connect to the remote device (please grant access in Settings > Privacy > Other Devices");
                //return;
            }

            // TODO: Maybe automatic pairing?

            try {
                bluetoothDevice = await BluetoothDevice.FromIdAsync(devInfo.Id);
            } catch (Exception ex) {
                System.Diagnostics.Debug.WriteLine("Error: Couldn't get BluetoothDevice");
                return;
            }

            if (bluetoothDevice == null)
            {
                System.Diagnostics.Debug.WriteLine("Bluetooth Device returned null. Access Status = " + accessStatus.ToString());
            }

            // This should return a list of uncached Bluetooth services (so if the server was not active when paired, it will still be detected by this call
            var rfcommServices = await bluetoothDevice.GetRfcommServicesForIdAsync(
                RfcommServiceId.FromUuid(Constants.RfcommChatServiceUuid), BluetoothCacheMode.Uncached); // Maybe change to cached???

            if (rfcommServices.Services.Count > 0)
            {
                service = rfcommServices.Services[0];
            }
            else
            {
                System.Diagnostics.Debug.WriteLine("Error: Could not discover the chat service on the remote device");
                System.Diagnostics.Debug.WriteLine("Paired: " + devInfo.Pairing.IsPaired);
                System.Diagnostics.Debug.WriteLine("Connection Status: " + bluetoothDevice.ConnectionStatus);
                return;
            }

            // Do various checks of the SDP record to make sure you are talking to a device that actually supports the Bluetooth Rfcomm Chat Service
            var attributes = await service.GetSdpRawAttributesAsync();

            if (!attributes.ContainsKey(Constants.SdpServiceNameAttributeId))
            {
                System.Diagnostics.Debug.WriteLine(
                    "The service is not advertising the Service Name attribute (attribute id=0x100).");
                return;
            }
            var attributeReader = DataReader.FromBuffer(attributes[Constants.SdpServiceNameAttributeId]);
            var attributeType   = attributeReader.ReadByte();

            if (attributeType != Constants.SdpServiceNameAttributeType)
            {
                System.Diagnostics.Debug.WriteLine(
                    "The Chat service is using an unexpected format for the Service Name attribute. ");
                return;
            }
            var serviceNameLength = attributeReader.ReadByte();

            // The Service Name attribute requires UTF-8 encoding.
            attributeReader.UnicodeEncoding = Windows.Storage.Streams.UnicodeEncoding.Utf8;

            StopWatcher();

            lock (this) {
                socket = new StreamSocket();
            }
            try {
                await socket.ConnectAsync(service.ConnectionHostName, service.ConnectionServiceName);

                writer = new DataWriter(socket.OutputStream);
                reader = new DataReader(socket.InputStream);

                System.Diagnostics.Debug.WriteLine("Connected to Server");
                isConnected = true;
                OnConnected();

                mainLoop();
            } catch (Exception ex) when((uint)ex.HResult == 0x80070490)   // ERROR_ELEMENT_NOT_FOUND
            {
                System.Diagnostics.Debug.WriteLine("Please verify that you are running the BluetoothRfcommChat server.");
            } catch (Exception ex) when((uint)ex.HResult == 0x80072740)    // WSAEADDRINUSE
            {
                System.Diagnostics.Debug.WriteLine("Please verify that there is no other RFCOMM connection to the same device.");
            }
        }
Exemple #3
0
        public async void ConnectAsync(RfcommChatDeviceDisplay deviceInfoDisp)
        {
            // Perform device access checks before trying to get the device.
            // First, we check if consent has been explicitly denied by the user.
            DeviceAccessStatus accessStatus = DeviceAccessInformation.CreateFromId(deviceInfoDisp.Id).CurrentStatus;

            if (accessStatus == DeviceAccessStatus.DeniedByUser)
            {
                throw new UnauthorizedAccessException("This app does not have access to connect to the remote device (please grant access in Settings > Privacy > Other Devices");
            }
            // If not, try to get the Bluetooth device
            try
            {
                bluetoothDevice = await BluetoothDevice.FromIdAsync(deviceInfoDisp.Id);
            }
            catch (Exception ex)
            {
                throw ex;
            }
            // If we were unable to get a valid Bluetooth device object,
            // it's most likely because the user has specified that all unpaired devices
            // should not be interacted with.
            if (bluetoothDevice == null)
            {
                throw new InvalidOperationException("Bluetooth Device returned null. Access Status = " + accessStatus.ToString());
            }

            // This should return a list of uncached Bluetooth services (so if the server was not active when paired, it will still be detected by this call
            var rfcommServices = await bluetoothDevice.GetRfcommServicesForIdAsync(
                RfcommServiceId.FromUuid(RfcommChatServiceUuid), BluetoothCacheMode.Uncached);

            if (rfcommServices.Services.Count > 0)
            {
                chatService = rfcommServices.Services[0];
            }
            else
            {
                throw new InvalidOperationException("Could not discover the chat service on the remote device");
            }

            // Do various checks of the SDP record to make sure you are talking to a device that actually supports the Bluetooth Rfcomm Chat Service
            var attributes = await chatService.GetSdpRawAttributesAsync();

            if (!attributes.ContainsKey(SdpServiceNameAttributeId))
            {
                throw new InvalidOperationException("The Chat service is not advertising the Service Name attribute (attribute id=0x100). " +
                                                    "Please verify that you are running the BluetoothRfcommChat server.");
            }
            var attributeReader = DataReader.FromBuffer(attributes[SdpServiceNameAttributeId]);
            var attributeType   = attributeReader.ReadByte();

            if (attributeType != SdpServiceNameAttributeType)
            {
                throw new InvalidOperationException(
                          "The Chat service is using an unexpected format for the Service Name attribute. " +
                          "Please verify that you are running the BluetoothRfcommChat server.");
            }
            var serviceNameLength = attributeReader.ReadByte();

            // The Service Name attribute requires UTF-8 encoding.
            attributeReader.UnicodeEncoding = Windows.Storage.Streams.UnicodeEncoding.Utf8;

            lock (this)
            {
                chatSocket = new StreamSocket();
            }
            try
            {
                await chatSocket.ConnectAsync(chatService.ConnectionHostName, chatService.ConnectionServiceName);

                // TODO: powiadomienie, że połączono
                //SetChatUI(attributeReader.ReadString(serviceNameLength), bluetoothDevice.Name);

                chatWriter = new DataWriter(chatSocket.OutputStream);
                DataReader chatReader = new DataReader(chatSocket.InputStream);

                ReceiveDataLoop(chatReader);
            }
            catch (Exception ex) when((uint)ex.HResult == 0x80070490)  // ERROR_ELEMENT_NOT_FOUND
            {
                throw new InvalidOperationException("Please verify that you are running the BluetoothRfcommChat server.");
            }
            catch (Exception ex) when((uint)ex.HResult == 0x80072740)  // WSAEADDRINUSE
            {
                throw new InvalidOperationException("Please verify that there is no other RFCOMM connection to the same device.");
            }
        }
Exemple #4
0
        private async void ConnectGenericDevice()
        {
            if (ChosenDevice != null)
            {
                await CheckBluetoothStatus(true);     // check bluetooth status and activate it if is turned off

                if (!IsBluetoothEnabled)
                {
                    AddLog("Can not connect with bluetooth disabled. Turn on the Bluetooth and try again.", AppLog.LogCategory.Warning);
                    return;
                }

                // request access to the selected device
                BluetoothDevice = await BluetoothLEDevice.FromIdAsync(ChosenDevice.Id);

                DeviceAccessStatus accessStatus = await BluetoothDevice.RequestAccessAsync();

                // log
                AddLog("[Connection: " + accessStatus.ToString() + "]" + " Connecting to " + BluetoothDevice.Name + "...", AppLog.LogCategory.Debug);
                AddLog("Connecting to " + BluetoothDevice.Name + "...", AppLog.LogCategory.Info);

                GattCharacteristicsResult hrGattCHaracteristics = null;

                // try to read the device charateristics
                try {
                    var gattDeviceServicesResult = await BluetoothDevice.GetGattServicesForUuidAsync(HRserviceGuid);        // get services with the HR service GUID

                    // for each service withe the given GUID try to read get
                    foreach (GattDeviceService service in gattDeviceServicesResult.Services)
                    {
                        AddLog("[" + ChosenDevice.Name + "] Found service. " +
                               "\n - Handle: " + service.AttributeHandle.ToString() +
                               "\n - UUID: " + service.Uuid.ToString(), AppLog.LogCategory.Debug);    // log

                        if (await service.GetCharacteristicsForUuidAsync(HRCharacteristicGuid) != null)
                        {
                            hrGattCHaracteristics = await service.GetCharacteristicsForUuidAsync(HRCharacteristicGuid);

                            HRReaderService = service;
                            break;
                        }
                    }
                } catch {
                    AddLog("Device \"" + ChosenDevice.Name + "\" does not support HR service." +
                           "\nSelect another one from the devices list.", AppLog.LogCategory.Warning);

                    return;
                }

                // get the HR reader characteristic
                if (hrGattCHaracteristics != null)
                {
                    foreach (GattCharacteristic characteristic in hrGattCHaracteristics.Characteristics.Where(c => c.Uuid.Equals(HRCharacteristicGuid)))
                    {
                        HRReaderCharacteristic = characteristic;
                    }
                }
                else
                {
                    // log something
                    return;
                }

                // if HR characteristic can't be found, show an error and return
                if (HRReaderCharacteristic == null)
                {
                    AddLog("Heart rate monitor characteristic NOT found.", AppLog.LogCategory.Debug);
                    AddLog("Could not connect to Heart Rate service of the device \"" + ChosenDevice.Name + "\".", AppLog.LogCategory.Warning);
                    return;
                }
                // if HR characteristic have been found, then start reading process
                else
                {
                    AddLog("Heart rate monitor characteristic found [Handle: " +
                           HRReaderCharacteristic.AttributeHandle.ToString() + "]", AppLog.LogCategory.Debug);

                    BeginBluetoothReadProcess();

                    SwitchConnectButtonToDisconnectButton();
                }
            }
            else
            {
                AddLog("The button should be disabled. Kowalski analisis.", AppLog.LogCategory.Debug);
                return;
            }
        }
        public async Task <bool> BtConnect(string deviceID)
        {
            try
            {
                //System.Diagnostics.Debug.Assert(Thread.CurrentThread.IsBackground, "SerialComm:BtConnect() cannot be called from the UI thread.");

                DeviceAccessStatus accessStatus = DeviceAccessInformation.CreateFromId(deviceID).CurrentStatus;
                if (accessStatus == DeviceAccessStatus.DeniedByUser)
                {
                    //await OBD2Xam.MainPage.Instance.DisplayAlert("Error",
                    //    "This app does not have access to connect to the remote device.  Please grant access in Settings > Privacy > Other Devices.",
                    //    "Cancel");
                    await Xamarin.Forms.Device.InvokeOnMainThreadAsync(
                        () => { OBD2Xam.MainPage.Instance.DisplayAlert("Error",
                                                                       "This app does not have access to connect to the remote device.  Please grant access in Settings > Privacy > Other Devices.",
                                                                       "Cancel"); }
                        );

                    return(false);
                }

                BluetoothDevice device = await BluetoothDevice.FromIdAsync(deviceID);

                if (device == null)
                {
                    //rootPage.NotifyUser("Bluetooth Device returned null. Access Status = " + accessStatus.ToString(), NotifyType.ErrorMessage);
                    System.Diagnostics.Debug.WriteLine("Bluetooth Device returned null. Access Status = " + accessStatus.ToString());
                    System.Diagnostics.Debugger.Break();
                    return(false);
                }
                //System.Diagnostics.Debug.WriteLine(device.ConnectionStatus);

                DeviceAccessStatus das;
                das = await device.RequestAccessAsync();  // might not always work...

                //System.Diagnostics.Debugger.Break();

                /*
                 * // RequestAccessAsync() needs to executed on the UI thread, which means the UI thread cannot be blocked
                 * // while waiting for all this other crap to run.  So this code needs to be executed in backround,
                 * // WITHOUT an await, because that would cause the UI thread to block.
                 * bool invokeComplete = false;
                 * Xamarin.Forms.Device.BeginInvokeOnMainThread( async () => {
                 *  das = await device.RequestAccessAsync();
                 *  invokeComplete = true;
                 * });
                 *
                 * // now we wait for the UI thread to finish it's task, without await
                 * // because BeginInvokeOnMainThread() isn't awaitable.
                 * while (!invokeComplete)
                 * {
                 *  System.Diagnostics.Debug.WriteLine("waiting...");
                 *  System.Threading.Thread.Sleep(100);
                 * }
                 */

                if (das == DeviceAccessStatus.Allowed)
                {
                    RfcommDeviceServicesResult rfResultList = await device.GetRfcommServicesAsync().AsTask().ConfigureAwait(false);

                    logRfTypes(rfResultList);

                    // https://blog.j2i.net/2018/07/29/connecting-to-bluetooth-rfcomm-with-uwp/
                    if (rfResultList.Services.Count > 0)
                    {
                        foreach (var service in rfResultList.Services)
                        {
                            if (service.ServiceId.AsString() == Constants.BT_SERIAL_PORT_INTERFACE)
                            {
                                streamSocket = new StreamSocket();
                                await streamSocket.ConnectAsync(service.ConnectionHostName, service.ConnectionServiceName);

                                dw = new DataWriter(streamSocket.OutputStream);
                                sr = new StreamReader(streamSocket.InputStream.AsStreamForRead(256));
                                break;
                            }
                        }
                        if (!IsOpen())
                        {
                            throw new Exception("Service not found)");
                        }
                    }
                }
            }
            catch (Exception exc)
            {
                if (exc.Message == "Element not found. (Exception from HRESULT: 0x80070490)")
                {
                    //System.Diagnostics.Debug.WriteLine("Device not listening.");
                    await Xamarin.Forms.Device.InvokeOnMainThreadAsync(
                        () => { OBD2Xam.MainPage.Instance.DisplayAlert("Error", "Device not listening.", "Cancel"); }
                        );

                    this.Close();
                }
                else
                {
                    System.Diagnostics.Debug.WriteLine(exc.Message);
                    System.Diagnostics.Debugger.Break();
                }
            }


            return(IsOpen());
        }
Exemple #6
0
        /// <summary>
        /// Invoked once the user has selected the device to connect to.
        /// Once the user has selected the device,
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public async Task <bool> ConnectAsync(RomeRemoteSystem system)
        {
            // Make sure user has selected a device first
            if (system != null)
            {
                Debug.WriteLine("Connecting to remote device. Please wait...");
            }
            else
            {
                Debug.WriteLine("Please select an item to connect to");
                return(false);
            }

            // Perform device access checks before trying to get the device.
            // First, we check if consent has been explicitly denied by the user.
            DeviceAccessStatus accessStatus = DeviceAccessInformation.CreateFromId(system.Id).CurrentStatus;

            if (accessStatus == DeviceAccessStatus.DeniedByUser)
            {
                Debug.WriteLine("This app does not have access to connect to the remote device (please grant access in Settings > Privacy > Other Devices");
                return(false);
            }

            // If not, try to get the Bluetooth device
            try
            {
                _bluetoothDevice = await BluetoothDevice.FromIdAsync(system.Id);
            }
            catch (Exception ex)
            {
                Debug.WriteLine(ex.Message);
                StopWatcher();
                return(false);
            }

            // If we were unable to get a valid Bluetooth device object,
            // it's most likely because the user has specified that all unpaired devices
            // should not be interacted with.
            if (_bluetoothDevice == null)
            {
                Debug.WriteLine("Bluetooth Device returned null. Access Status = " + accessStatus.ToString());
            }

            if (_bluetoothDevice == null)
            {
                return(false);
            }

            // This should return a list of uncached Bluetooth services (so if the server was not active when paired, it will still be detected by this call
            var rfcommServices = await _bluetoothDevice?.GetRfcommServicesForIdAsync(
                RfcommServiceId.FromUuid(Constants.SERVICE_UUID), BluetoothCacheMode.Uncached);

            if (rfcommServices?.Services.Count > 0)
            {
                _chatService = rfcommServices.Services[0];
            }
            else
            {
                Debug.WriteLine("Could not discover the chat service on the remote device");
                StopWatcher();
                return(false);
            }

            // Do various checks of the SDP record to make sure you are talking to a device that actually supports the Bluetooth Rfcomm Chat Service
            var attributes = await _chatService.GetSdpRawAttributesAsync();

            if (!attributes.ContainsKey(Constants.SERVICE_ATTRIBUTE_ID))
            {
                Debug.WriteLine(
                    "The Chat service is not advertising the Service Name attribute (attribute id=0x100). " +
                    "Please verify that you are running the BluetoothRfcommChat server.");
                StopWatcher();
                return(false);
            }
            var attributeReader = DataReader.FromBuffer(attributes[Constants.SERVICE_ATTRIBUTE_ID]);
            var attributeType   = attributeReader.ReadByte();

            if (attributeType != Constants.SERVICE_ATTRIBUTE_TYPE)
            {
                Debug.WriteLine(
                    "The Chat service is using an unexpected format for the Service Name attribute. " +
                    "Please verify that you are running the BluetoothRfcommChat server.");
                StopWatcher();
                return(false);
            }

            var serviceNameLength = attributeReader.ReadByte();

            // The Service Name attribute requires UTF-8 encoding.
            attributeReader.UnicodeEncoding = Windows.Storage.Streams.UnicodeEncoding.Utf8;

            StopWatcher();

            lock (this)
            {
                _chatSocket = new StreamSocket();
            }
            try
            {
                await _chatSocket.ConnectAsync(_chatService.ConnectionHostName, _chatService.ConnectionServiceName);

                Debug.WriteLine("Connected to : " + attributeReader.ReadString(serviceNameLength) + _bluetoothDevice.Name);
                _chatWriter = new DataWriter(_chatSocket.OutputStream);

                DataReader chatReader = new DataReader(_chatSocket.InputStream);
                ReceiveStringLoop(chatReader);

                return(true);
            }
            catch (Exception ex) when((uint)ex.HResult == 0x80070490)  // ERROR_ELEMENT_NOT_FOUND
            {
                Debug.WriteLine("Please verify that you are running the BluetoothRfcommChat server.");
                StopWatcher();
            }
            catch (Exception ex) when((uint)ex.HResult == 0x80072740)  // WSAEADDRINUSE
            {
                Debug.WriteLine("Please verify that there is no other RFCOMM connection to the same device.");
                StopWatcher();
            }

            return(false);
        }
Exemple #7
0
        //Connect to the chosen device
        private async void ConnectDevice()
        {
            if (DeviceInterfacesOutputLst.SelectedItem != null)
            {
                string DeviceID = "";                                                                                             //Device ID
                foreach (var device in devices.Where(device => device.Name == DeviceInterfacesOutputLst.SelectedItem.ToString())) //selext the chosen device from the listview
                {
                    DeviceID = device.Id;
                }
                BluetoothDevice = await BluetoothLEDevice.FromIdAsync(DeviceID);   //request access to the Device

                DeviceAccessStatus x = await BluetoothDevice.RequestAccessAsync(); //wait for the permission

                OutputList.Items.Insert(0, "Connection: " + x.ToString() + " - BluetoothLE Device is " + BluetoothDevice.Name);
                //Create the service and characteristic values to fill with the chosen device information
                GattDeviceService         HRservice         = null;
                GattCharacteristicsResult HRcharacteristics = null;

                try //read the device characteristics, if the characteristics are not found, an exception get thrown
                {
                    HRservice         = BluetoothDevice.GetGattService(HRserviceGuid);
                    HRcharacteristics = await HRservice.GetCharacteristicsAsync();
                }
                catch
                {
                    OutputList.Items.Insert(0, "Chosen device does not support HR service, choose another one");
                    return;
                }
                //TFind the characteristics UUID and assign them to the variable
                foreach (GattCharacteristic caratteristica in HRcharacteristics.Characteristics.Where(caratteristica => caratteristica.Uuid.Equals(HRMeasurement)))
                {
                    HRreader = caratteristica; //assegno la caratteristica ad HRreader
                    OutputList.Items.Insert(0, "Heart Rate Monitor characteristic found - Handle: " + HRreader.AttributeHandle.ToString());
                }

                //check the server port data
                try
                {
                    int serverPortInt;
                    serverPortInt = Int32.Parse(tcpPortText.Text);
                    serverPort    = tcpPortText.Text;
                }
                catch
                {
                    OutputList.Items.Insert(0, "Invalid TCP Port, using 13000");
                    tcpPortText.Text = "13000";
                    serverPort       = tcpPortText.Text;
                }

                if (HRreader == null)//if the HR characteristic in not found, show an error
                {
                    OutputList.Items.Insert(0, "Heart Rate Monitor characteristic not found");
                }
                else //If the characteristic have been found, start the readings
                {
                    //Requesting notify
                    //NOTE: we are not allowed to read the value on request, we have to ask the device to be notified when the HR value change
                    GattCommunicationStatus status = GattCommunicationStatus.ProtocolError; //setting the status as "protocol error", just in case...
                    OutputList.Items.Insert(0, "Waiting for notify handshake...");

                    try
                    {
                        status = await HRreader.WriteClientCharacteristicConfigurationDescriptorAsync(
                            GattClientCharacteristicConfigurationDescriptorValue.Notify);
                    }
                    catch
                    {
                        //f**k, i don't know
                    }

                    //We are now ready to receive the informations and send them via TCP
                    if (status == GattCommunicationStatus.Success)
                    {
                        OutputList.Items.Insert(0, "Notify Activated");
                        OutputList.Items.Insert(0, "Now reading... give me a few seconds");
                        deviceConnectionState = true;
                        serverPort            = tcpPortText.Text;
                        OutputList.Items.Insert(0, "Connecting to port " + serverPort);

                        DispatcherTimerSetup();
                        read();
                    }
                    else
                    {
                        if (status == GattCommunicationStatus.ProtocolError)
                        {
                            OutputList.Items.Insert(0, "Notify Failed - Protocol Error");
                        }
                        if (status == GattCommunicationStatus.Unreachable)
                        {
                            OutputList.Items.Insert(0, "Notify Failed - Unreachable");
                        }
                        if (status == GattCommunicationStatus.AccessDenied)
                        {
                            OutputList.Items.Insert(0, "Notify Failed - Access Denied");
                        }
                        OutputList.Items.Insert(0, "Sorry, I'm far from perfect");
                    }
                }
            }
            else
            {
                OutputList.Items.Insert(0, "Select a device from the list"); //nel caso in cui non venga selezionato un dispositivo dalla lista
            }
        }