SWIFT - BLE communications
<p>I've got a SWIFT application that have to send a value to my Arduino with Bluetooth LowEnergy module!</p>

<p>I've done correctly the search and connection parts but I'm not able to send and receive any data.</p>

<p>Here is my code to get a list of BLE devices available and put all this in a table view then after click in a cell the app provide to connect the device with them!</p>

<p>All this works perfectly but I don't know to send for example a "a" character from app to BLE and get back the answer from arduino to app!</p>

<pre><code>    import UIKit
    import CoreBluetooth


class BluetoothList: UITableViewController,CBCentralManagerDelegate, CBPeripheralDelegate {

    var listValue = [Lista]()
    var Blue: CBCentralManager!
    var conn: CBPeripheral!
    var a: String!
    var char: CBCharacteristic!

    func centralManager(central: CBCentralManager, didDiscoverPeripheral peripheral: CBPeripheral, advertisementData: [String : AnyObject], RSSI: NSNumber) {
        if (peripheral.name == a){
            self.conn = peripheral
            self.conn.delegate = self
            Blue.stopScan()
            Blue.connectPeripheral(self.conn, options: nil)
            self.performSegueWithIdentifier("ConnectionSegue", sender: nil)
        }
        else{
            listValue = [
                Lista(Name: peripheral.name!, RSS: RSSI.stringValue)
            ]
            self.tableView.reloadData()
        }
    }

    func centralManager(central: CBCentralManager, didConnectPeripheral peripheral: CBPeripheral) {
        peripheral.delegate = self
        peripheral.discoverServices(nil)

    }

    func peripheral(peripheral: CBPeripheral, didDiscoverServices error: NSError?) {
        if let servicePeripheral = peripheral.services! as [CBService]!{
            for service in servicePeripheral{
                peripheral.discoverCharacteristics(nil, forService: service)
            }
        }
    }

    func peripheral(peripheral: CBPeripheral, didDiscoverCharacteristicsForService service: CBService, error: NSError?) {
        if let characterArray = service.characteristics! as [CBCharacteristic]!{

            for cc in characterArray {
                if(cc.UUID.UUIDString == "FF05"){
                    print("OKOK")
                    peripheral.readValueForCharacteristic(cc)
                }
            }
        }
    }

    func peripheral(peripheral: CBPeripheral, didUpdateValueForCharacteristic characteristic: CBCharacteristic, error: NSError?) {
        if (characteristic.UUID.UUIDString == "FF05"){

            let value = UnsafePointer&lt;Int&gt;((characteristic.value?.bytes.memory)!)
            print("\(value)")
        }
    }

    func centralManagerDidUpdateState(central: CBCentralManager){
        switch(central.state){
        case .PoweredOn:
            Blue.scanForPeripheralsWithServices(nil, options:nil)
            print("Bluetooth is powered ON")
        case .PoweredOff:
            print("Bluetooth is powered OFF")
        case .Resetting:
            print("Bluetooth is resetting")
        case .Unauthorized:
            print("Bluetooth is unauthorized")
        case .Unknown:
            print("Bluetooth is unknown")
        case .Unsupported:
            print("Bluetooth is not supported")
        }
    }

    override func viewDidLoad() {

        super.viewDidLoad()
        Blue = CBCentralManager(delegate: self, queue: nil)

    }

    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        let currentCell = tableView.cellForRowAtIndexPath(tableView.indexPathForSelectedRow!)! as UITableViewCell
        a = currentCell.textLabel?.text
        Blue = CBCentralManager(delegate: self, queue: nil)
    }

    override func numberOfSectionsInTableView(tableView: UITableView) -&gt; Int {
        return 1
    }

    @IBAction func Reload_BTN(sender: AnyObject) {
        self.tableView.reloadData()
    }

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -&gt; Int {
        return self.listValue.count
    }


    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }


    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -&gt; UITableViewCell {

        let cella = self.tableView.dequeueReusableCellWithIdentifier("Cella", forIndexPath: indexPath)
        let Lista = self.listValue[indexPath.row]
        cella.textLabel?.text = Lista.Name
        cella.accessoryType = UITableViewCellAccessoryType.DisclosureIndicator
        return cella
    }
</code></pre>