code: func NewMotorDriver(a DigitalWriter, speedPin string) *MotorDriver {
  	return &MotorDriver{
  		name:             gobot.DefaultName("Motor"),
  		connection:       a,
  		SpeedPin:         speedPin,
  		CurrentState:     0,
  		CurrentSpeed:     0,
  		CurrentMode:      "digital",
  		CurrentDirection: "forward",
  	}
  }
docs: // NewMotorDriver return a new MotorDriver given a DigitalWriter and pin