Motor Block

This block allows for precise control of one motor’s speed. You can "ramp up" to a set speed or "ramp down" to a stop. By deselecting "Wait for Completion," your program can move on to the next block once the Motor block has started a motor.

1. The letter at the top right corner of the block shows which NXT port is set to control a motor.
2. This icon shows which direction the motor will go.
3. This icon shows the power level.
4. This icon shows whether you have set the Duration property to unlimited, degrees, rotations, or seconds.
5. You can change values dynamically by connecting data wires to this block’s data hub. (See the Data Hub section below for more information.)

1. This icon shows that the Direction property is set to "stop". This setting will stop the indicated motor.

Configuring the Motor Block

1. Select the motor you’d like to control.
2. Choose whether the motor should go forwards, go backwards, or stop.
3. You can precisely control the acceleration of the motor by selecting "Ramp Up" or "Ramp Down." A motor set to "Ramp Up" will slowly increase its speed until it reaches specified power. A motor set to "Ramp Down" will slowly decrease its speed until it reaches zero power. A motor set to "Constant" will reach full power immediately and will stop quickly by either coasting or braking (depending on the setting).
4. This slider and the editable input box will let you set the power level [0-100%].
5. Select this checkbox if you’d like to turn on power control. Power control will attempt to compensate for any resistance or slippage that the motor encounters. It will increase power to a maximum of 100% to maintain the same rotation amount per second.
6. Using the Duration pull-down menu, set the motor to run for an unlimited interval or for a set number of rotations, degrees, or seconds.
7. With "Wait for completion" selected, the motor will finish its action completely before allowing the program to move on. If you de-select "Wait for completion," other blocks in the program can proceed while your motor completes its action. For example, a Sound block placed after the Motor block could start playing a sound file while the motor continues its action.
8. Choose whether the motor will brake or coast after finishing its action. Set the motor to brake if you want it to stop precisely at an exact position and (attempt to) hold that position. Braking does require additional battery power because the motor does extra work to maintain the position. Coast is a good choice if this block is followed by another block controlling the same motor.
9. The feedback boxes will count how many degrees or full rotations your motor turns. Press the reset button to return the values to zero. (To receive feedback, make sure that the motor is connected to the chosen port and that communication has been established with the NXT.)

Motor versus Robot Direction

When you set a Move or Motor blocks' direction, you are specifying the direction the motor will spin. This may be different than the direction your robot actually moves. Depending on how you build your robotic invention, setting the motors to go forwards may cause your creation to move backwards. The image below shows a motor spinning in the default, forwards direction.

Configuring the Motor block’s Data Hub

You can control the Motor block dynamically by connecting data wires (from other blocks’ data hubs) to the Motor block’s data hub.

Open a block’s data hub by clicking the tab at the lower left edge of the block after it has been placed on the work area.

Data wires carrying input information to a block are connected to the plugs on the left side of its data hub. Data wires carrying output information are connected to the plugs on the right side.

[A] Input plug
[B] Output plug
[C] Number data wire (yellow)
[D] Logic data wire (green)
[E] Text data wire (orange)
[F] Broken data wire (gray)

Passing data from the input plug to the output plug

If an input plug has a corresponding output plug (see A above), the input data will pass through from the input plug to the output plug without being changed. In this case, you can only use the output plug if the input plug is connected to an input data wire; connecting an output data wire to such an output plug without a connected input data wire will cause the output data wire to be "broken" (and colored gray).

Data wires carry specific types of data

Each data wire carries a specific type of data between blocks. For example, if a data wire is dragged from a logic plug on a block’s data hub, it can only be connected to a logic plug on another block’s data hub. The chart below shows what kind of data each plug can accept or send out.

Data wire colors

Data wires are identified with specific colors: wires carrying number data are colored yellow, wires carrying logic data are colored green, and wires carrying text data are colored orange.

"Broken" data wires

If you try to connect a data wire to a plug of the wrong data type, the data wire will be broken (and colored gray). You will not be able to download your program if a data wire is broken.

If you click a broken wire you can read why it is broken in the small help window in the lower right corner of the work area.

Data must be within the possible range of the plug

If an input data wire transmits a value outside the possible range of the plug it is connected to, the block will either ignore the value or change it to a value within its range. For plugs that allow just a few input values (example: just 0, 1, or 2), the plug will ignore the input if a value arrives outside its range.

For plugs that accept larger input ranges (example: 0 – 100), the plug will force any input outside its range to fit. For example, if a Move block’s Power plug receives an input value of 150, the block will change the input value to 100 (i.e., a number within the Power plug’s range).

This chart shows the different characteristics of the plugs on the Motor block’s data hub:

	Plug	Data Type	Possible Range	What the Values Mean	This Plug is Ignored When...
	Port	Number	1 - 3	1 = A, 2 = B, 3 = C
	Direction	Logic	True/False	True = Forwards False = Backwards
	Action	Number	0 - 2	0 = Constant 1 = Ramp Up 2 = Ramp Down	Duration Type = Unlimited or Seconds
	Power	Number	0 - 100
	Control Motor Power	Logic	True/False
	Duration	Number	0 - 2147483647	Depends on Duration Type: Degrees/Rotations = Degrees, Seconds = Seconds	Duration Type = Unlimited
	Wait for Completion	Logic	True/False		Duration Type = Unlimited (always False), Seconds (always True)
	Next Action	Logic	True/False	True = Brake False = Coast	Duration Type = Unlimited, or Wait for Completion = False
	Direction out	Logic	True/False	Direction the motor moved during the block’s execution. True = Forwards False = Backwards
	Degrees out	Number	0 - 2147483647	How many degrees the motor moved during the block's execution