Lesson 2: Activate a Motor with a Controller Button

Building on the motor definition from Lesson 1, this lesson wires your motor to an Xbox controller button so it runs while the button is held and automatically stops the moment it is released. This pattern is foundational in FRC robot programming — almost every operator-controlled mechanism uses the same whileTrue / onFalse binding structure.

What You’ll Learn

How to create a CommandXboxController and which port number the operator controller uses
How to retrieve a Trigger from a specific button (button B in this lesson)
The difference between .whileTrue() and .onFalse() and why you need both
How to write an inline RunCommand lambda to set motor speed on the fly
The motor speed range: -1.0 (full reverse) → 0.0 (stopped) → 1.0 (full forward)

Solutions by Motor Type

NEO (SparkMax)
Kraken (TalonFX)
CIM (PWMSparkMax)

The motor runs at 50% forward while B is held and stops when B is released. Button binding lives inside robotInit().

import edu.wpi.first.wpilibj.TimedRobot;
import edu.wpi.first.wpilibj2.command.CommandXboxController;
import edu.wpi.first.wpilibj2.command.RunCommand;
import edu.wpi.first.wpilibj2.command.InstantCommand;
import com.revrobotics.spark.SparkMax;
import com.revrobotics.spark.SparkLowLevel.MotorType;

public class Robot extends TimedRobot {
    private final SparkMax m_motor = new SparkMax(1, MotorType.kBrushless);
    private final CommandXboxController driverController = new CommandXboxController(0);
    private final CommandXboxController operatorController = new CommandXboxController(1);

    @Override
    public void robotInit() {
        operatorController.b()
            .whileTrue(new RunCommand(() -> {
                m_motor.set(0.5);
            }))
            .onFalse(new InstantCommand(() -> {
                m_motor.set(0.0);
            }));
    }
}

The Kraken uses DutyCycleOut control requests instead of .set(). The binding structure is identical — only the motor API differs.

import edu.wpi.first.wpilibj.TimedRobot;
import edu.wpi.first.wpilibj2.command.CommandXboxController;
import edu.wpi.first.wpilibj2.command.RunCommand;
import edu.wpi.first.wpilibj2.command.InstantCommand;
import com.ctre.phoenix6.hardware.TalonFX;
import com.ctre.phoenix6.controls.DutyCycleOut;

public class Robot extends TimedRobot {
    private final TalonFX m_motor = new TalonFX(1, "DINO");
    private final CommandXboxController driverController = new CommandXboxController(0);
    private final CommandXboxController operatorController = new CommandXboxController(1);

    @Override
    public void robotInit() {
        operatorController.b()
            .whileTrue(new RunCommand(() -> {
                m_motor.setControl(new DutyCycleOut(0.5));
            }))
            .onFalse(new InstantCommand(() -> {
                m_motor.setControl(new DutyCycleOut(0.0));
            }));
    }
}

CIM motors use the same .set() API as NEO. The only difference is the class name and import.

import edu.wpi.first.wpilibj.TimedRobot;
import edu.wpi.first.wpilibj2.command.CommandXboxController;
import edu.wpi.first.wpilibj2.command.RunCommand;
import edu.wpi.first.wpilibj2.command.InstantCommand;
import edu.wpi.first.wpilibj.motorcontrol.PWMSparkMax;

public class Robot extends TimedRobot {
    private final PWMSparkMax m_motor = new PWMSparkMax(0);
    private final CommandXboxController driverController = new CommandXboxController(0);
    private final CommandXboxController operatorController = new CommandXboxController(1);

    @Override
    public void robotInit() {
        operatorController.b()
            .whileTrue(new RunCommand(() -> {
                m_motor.set(0.5);
            }))
            .onFalse(new InstantCommand(() -> {
                m_motor.set(0.0);
            }));
    }
}

Key Concepts

operatorController.b() Calling .b() on a CommandXboxController returns a Trigger object that is active (true) whenever the B button is physically pressed. You chain .whileTrue() and .onFalse() directly onto this trigger. .whileTrue(command) Schedules the given command every scheduler cycle while the trigger condition is true (i.e., while the button stays held). When the button is released the command is interrupted. .onFalse(command) Schedules the given command on the falling edge — the instant the trigger transitions from true to false (button released). Using InstantCommand here ensures the motor is commanded to stop exactly once rather than continuously. new RunCommand(() -> { m_motor.set(0.5); }) RunCommand is a lightweight WPILib command that runs a single lambda (anonymous function) repeatedly while active. The lambda sets the motor output to 50% forward every scheduler tick. new InstantCommand(() -> { m_motor.set(0.0); }) InstantCommand runs its lambda exactly once and immediately finishes. It is the right choice for .onFalse() because stopping a motor is a one-time action, not a continuous one. Speed range Motor set() accepts a double from -1.0 to 1.0:

Value	Behavior
`1.0`	Full speed forward
`0.5`	50% speed forward
`0.0`	Stopped
`-0.5`	50% speed reverse
`-1.0`	Full speed reverse

In FRC Academy

To reach this lesson in the app:

Open the Main Menu

Launch FRC Academy and click Motors from the main menu.

Select a motor type

Choose NEO, Kraken, or CIM.

Open Lesson 2

Select 2. Activate a Single Motor from the lesson list.

Choose a mode

Pick Guided Mode or Unguided Mode and start writing.

The operator controller is always port 1 in FRC Academy motor lessons. The driver controller is port 0 and is used in the drivetrain lessons (Tank Drive). Make sure you pass the correct port when constructing each CommandXboxController.

← Define a Motor

Lesson 1 — Declare the motor hardware object with the correct import and constructor arguments.

2-Motor Tank Drive →

Lesson 3 — Control two motors with joystick axes to drive a differential drivetrain.

Get Started

Learning Paths

Motor Types

Lessons

Lesson 2: Activate a Motor with a Controller Button

What You’ll Learn

Solutions by Motor Type

Key Concepts

In FRC Academy

← Define a Motor

2-Motor Tank Drive →

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Get Started

Learning Paths

Motor Types

Lessons

Documentation Index

​What You’ll Learn

​Solutions by Motor Type

​Key Concepts

​In FRC Academy

← Define a Motor

2-Motor Tank Drive →

Build docs developers (and LLMs) love

What You’ll Learn

Solutions by Motor Type

Key Concepts

In FRC Academy