Move a stepper motor for the number of steps at the specified speed
        This is a FirmataPlus feature.

        :param motor_speed: 21 bits of data to set motor speed

        :param number_of_steps: 14 bits for number of steps & direction
                                positive is forward, negative is reverse

def stepper_step(self, motor_speed, number_of_steps):
        """
        Move a stepper motor for the number of steps at the specified speed
        This is a FirmataPlus feature.

        :param motor_speed: 21 bits of data to set motor speed

        :param number_of_steps: 14 bits for number of steps & direction
                                positive is forward, negative is reverse
        """
        task = asyncio.ensure_future(self.core.stepper_step(motor_speed,
                                                            number_of_steps))
        self.loop.run_until_complete(task)