code: function writeRaw(peripheralId, serviceUuid, uuid, data, withoutResponse, callback){
    //todo catch exceptions
    var handle = servicesCache[peripheralId].services[serviceUuid].characteristics[uuid].handle;
    var peripheral = peripherals[peripheralId];
  
    //if not connected, connect
    checkConnected(peripheral, function(){
      peripheral.writeHandle(handle, new Buffer(data,'hex'), withoutResponse, function(error){
        if (error) {
          debug('Write handle error! '. red + error);
        }
        debug('write handle sent ' + peripheralId + ' : ' + serviceUuid + ' : ' + uuid )
        sendEvent({
           type: 'write',
           peripheralId: peripheralId,
           serviceUuid: serviceUuid,
           characteristicUuid: uuid
        });
  
      });
    })
  }
docs: write by handle