 extension ViewController: DataCharacteristicDelegate {
     
     func found() {
-        _appendLog("Data characteristic found!")
+        dispatch_async(dispatch_get_main_queue(), {
+            self._appendLog("Data characteristic found!")
+        })
     }
     
     func dataRead(dataSize: Int) {

            return
        }
        
        _showRSSI(RSSI)
    }
}


    }

    func centralDidUpdateState(manager: BLECManager) {
        dispatch_async(dispatch_get_main_queue(), {
            self._appendLog(self._stateName(self._manager.state))
        })
    }

    func central(manager: BLECManager, didDiscoverPeripheral peripheral: CBPeripheral, RSSI: Int) {
        dispatch_async(dispatch_get_main_queue(), {
            self._appendLog("Discovered: \(peripheral.identifier.UUIDString)")
            self._showRSSI(RSSI)
        })
    }

    func central(central: BLECManager, didConnectPeripheral peripheral: CBPeripheral) {
        dispatch_async(dispatch_get_main_queue(), {
            self._appendLog("Connected \(peripheral.identifier.UUIDString)")
            self._timer = NSTimer.scheduledTimerWithTimeInterval(
                1.0,
                target: self,
                selector: #selector(self._update),
                userInfo: nil,
                repeats: true)
        })
    }

    func central(central: BLECManager, didCheckCharacteristicsDevice device: BLECDevice) {
