                 
                 // notification
                 assert(error == nil, "Notifications should never fail")
-                                
+                
                 let data = coreCharacteristic.value ?? Data()
                 
                 guard let cache = self.internalState.cache[Peripheral(corePeripheral)],

    public func writeValue(_ data: Data,
                           for characteristic: Characteristic<Peripheral>,
                           withResponse: Bool = true,
                           timeout: TimeInterval = 30) throws {
        
        guard state == .poweredOn
            else { throw DarwinCentralError.invalidState(state) }

        }
        
        self.log?("Scanning...")
        
        self.internalManager.scanForPeripherals(withServices: nil, options: options)
        
        // sleep until scan finishes
