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The Controllers lesson in FRC Academy teaches you how to wire up Xbox controllers so your robot can respond to human input. You’ll define two CommandXboxController objects — one for the driver (USB port 0) and one for the operator (USB port 1) — import the class from WPILib, and declare both as private final fields inside your robot class. By the end of this lesson, your robot code will be ready to accept event bindings like .whileTrue() and .onFalse() on any button.

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What You’ll Learn

  • Importing CommandXboxController from edu.wpi.first.wpilibj2.command
  • Declaring private final controller fields inline inside the robot class
  • Binding buttons with .whileTrue() and .onFalse() for event-driven command execution
  • Understanding driver vs. operator port assignments and why they must be different
  • The difference between CommandXboxController and the legacy XboxController class

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Guided Steps

The FRC Academy app walks you through four steps in the in-editor popup. Each step shows an instruction and the exact line of code to type.
1

Import CommandXboxController from WPILib

Add the import statement at the top of your file so Java knows where to find the class.
import edu.wpi.first.wpilibj2.command.CommandXboxController;
2

Declare driverController on port 0

Inside the robot class body, declare the driver’s controller as a private final field assigned to USB port 0.
private final CommandXboxController driverController = new CommandXboxController(0);
3

Declare operatorController on port 1

Below the driver declaration, add a second controller for the operator on port 1.
private final CommandXboxController operatorController = new CommandXboxController(1);
4

Click Verify Code

Once both declarations are in place, click the Verify Code button in the editor toolbar. FRC Academy will run a line-by-line diagnostic and highlight correct lines in green and any errors in red.

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The Solution

Here is the complete, verified solution that the FRC Academy Code Review modal checks against: 
import edu.wpi.first.wpilibj.TimedRobot;
import edu.wpi.first.wpilibj2.command.CommandXboxController;

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

    @Override
    public void robotInit() { }
}
The solution includes a TimedRobot import and an empty robotInit() override. FRC Academy verifies your code line-by-line against this exact solution, so be sure your whitespace and field names match.

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Key Classes

CommandXboxController (from edu.wpi.first.wpilibj2.command) is the modern WPILib class designed for the Command-Based robot paradigm. Its buttons return Trigger objects, which means you can attach command bindings directly:
operatorController.b()
    .whileTrue(new RunCommand(() -> m_motor.set(0.5)))
    .onFalse(new InstantCommand(() -> m_motor.set(0.0)));
XboxController (from edu.wpi.first.wpilibj) is the older class that only reads raw boolean/axis values. It does not support .whileTrue() or .onFalse() event binding and is not suitable for use with CommandScheduler. Use CommandXboxController for all new robot projects.

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Port Assignments

FRC uses USB port numbers to identify controllers plugged into the Driver Station laptop:
PortAssigned ToConvention
0Driver controllerPrimary driving, left/right joystick movement
1Operator controllerSecondary mechanisms, button-bound subsystem commands
Port numbers are set in the FRC Driver Station application under the USB tab. Make sure the correct controller appears at the right port number before running a match. If a controller is unplugged and re-plugged, the Driver Station may reassign its port — always double-check before enabling the robot.
If both controllers are assigned the same port number in your code, only one will respond. Always use port 0 for the driver and port 1 for the operator.
CommandXboxController is the modern WPILib approach for all Command-Based projects. See the API reference at /api/wpilib-commands for the full class details including all available button trigger methods.

API: CommandXboxController

Full class reference for CommandXboxController, RunCommand, and InstantCommand

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