This callback is called form the Crazyflie API when a Crazyflie
        has been connected and the TOCs have been downloaded.

def _connected(self, link_uri):
        """ This callback is called form the Crazyflie API when a Crazyflie
        has been connected and the TOCs have been downloaded."""
        print('Connected to %s' % link_uri)

        mems = self._cf.mem.get_mems(MemoryElement.TYPE_1W)
        self._mems_to_update = len(mems)
        print('Found {} 1-wire memories'.format(len(mems)))
        for m in mems:
            print('Updating id={}'.format(m.id))
            m.update(self._data_updated)