跳到主要内容

1:Quick Start of JavaScript on Micro:bit

Mastering JavaScript on the micro:bit​

Transitioning from Blocks to Static TypeScript (STS)—the version of JavaScript used in MakeCode—unlocks the full potential of Robot PU. This guide covers everything from the interface to advanced Object-Oriented Design.

1. The Programming Interface​

When you open makecode.microbit.org, you primarily work in the Blocks editor. To switch to JavaScript:

  1. Locate the toggle switch at the top center of the screen.
  2. Click JavaScript.
  3. The toolbox on the left remains, but clicking a category now provides code snippets instead of blocks.

2. Basic JavaScript Syntax​

STS is “strongly typed,” meaning it likes to know what kind of data you are using.

  • Variables: Use let for values that change and const for values that stay the same.
let speed = 100;
const robotName = "PU";
  • Functions: Wrap reusable logic in functions.
function waveHand() {
    pins.servoWritePin(AnalogPin.P1, 90);
    basic.pause(500);
    pins.servoWritePin(AnalogPin.P1, 0);
}
  • Loops: The basic.forever function is a special loop that runs your code repeatedly in the background.

3. Object-Oriented Design (OOD)​

Classes allow you to group data and behaviors together. This is how we build “drivers” for sensors like the Sonar on PU’s chest.

Example: A Simple Robot Component​

class LedEye {
    pin: DigitalPin;

    constructor(targetPin: DigitalPin) {
        this.pin = targetPin;
    }

    blink() {
        pins.digitalWritePin(this.pin, 1);
        basic.pause(200);
        pins.digitalWritePin(this.pin, 0);
    }
}

// Create an "instance" of the eye on Pin P16
let leftEye = new LedEye(DigitalPin.P16);
leftEye.blink();

4. Compilation and Uploading​

MakeCode compiles your JavaScript into a .hex file—a format the micro:bit hardware understands.

Step-by-Step Upload:

  1. Connect: Plug your micro:bit into your computer via USB.
  2. Download: Click the purple Download button.
  3. Transfer:
    • Direct (WebUSB): If your browser is paired, the code flashes instantly.
    • Manual: Drag the .hex file from your Downloads folder onto the MICROBIT drive on your computer.`
  4. Run: The yellow light on the back flashes during the transfer. Once it stops, the program starts automatically.

5. Tips for Clean and Reusable Code​

Writing “clean” code makes it easier for you (and others) to fix bugs later.

  • Use Descriptive Names: Instead of let x = 10, use let sonarDistance = 10.
  • The Single Responsibility Principle: A class or function should do one thing well. For example, a Sonar class should only handle measuring distance, not playing music.
  • Comment Your Logic: Use // to explain why you are doing something complex.
  • Avoid “Magic Numbers”: Instead of using 0.0171821 inside your logic, create a variable named SOUND_SPEED_CONSTANT.
  • Keep it Modular: Put your classes at the top of the file or in separate tabs to keep your main forever loop tidy.