Learn MBED-CPP with Real Code Examples

#include "mbed.h"

DigitalOut led(LED1);
InterruptIn button(USER_BUTTON);
int buttonCount = 0;

void updateUI() {
    printf("Button Count: %d\n", buttonCount);
    led = buttonCount % 2;
}

void buttonPressed() {
    buttonCount++;
    updateUI();
}

int main() {
    button.rise(&buttonPressed);
    updateUI();
    while(1) {}
}

Counts button presses and toggles an LED on each press.

#include "mbed.h"

DigitalOut led(LED1);

int main() {
    while(1) {
        led = !led;
        printf("LED is %s\n", led ? "ON" : "OFF");
        ThisThread::sleep_for(500ms);
    }
}

Blinks an LED every 500ms using a timer.

#include "mbed.h"

int temperature = 25;
bool alert = false;

void updateUI() {
    printf("Temperature: %d\n", temperature);
    if (alert) printf("Alert: High Temperature!\n");
}

void readSensor() {
    temperature += 2;
    alert = temperature > 30;
    updateUI();
}

int main() {
    updateUI();
    readSensor();
    readSensor();
}

Simulates reading temperature and printing alerts when high.

#include "mbed.h"

PwmOut led(LED1);
int brightness = 0;

void updateLED() {
    led.write(brightness / 100.0);
    printf("LED Brightness: %d\n", brightness);
}

void increaseBrightness() {
    brightness += 20;
    if(brightness > 100) brightness = 0;
    updateLED();
}

int main() {
    updateLED();
    increaseBrightness();
    increaseBrightness();
}

Adjusts LED brightness using PWM output.

#include "mbed.h"

DigitalOut relay(D2);
int state = 0;

void updateUI() {
    printf("Relay is %s\n", state ? "ON" : "OFF");
    relay = state;
}

void toggleRelay() {
    state = !state;
    updateUI();
}

int main() {
    updateUI();
    toggleRelay();
    toggleRelay();
}

Simulates a relay switch toggled by a button press.

#include "mbed.h"

DigitalOut buzzer(D3);
bool isOn = false;

void updateUI() {
    buzzer = isOn;
    printf("Buzzer is %s\n", isOn ? "ON" : "OFF");
}

void toggleBuzzer() {
    isOn = !isOn;
    updateUI();
}

int main() {
    updateUI();
    toggleBuzzer();
    toggleBuzzer();
}

Turns a buzzer on and off using a digital output.

#include "mbed.h"

PwmOut fan(D4);
int speed = 0;

void updateUI() {
    fan.write(speed / 5.0);
    printf("Fan Speed: %d\n", speed);
}

void increaseSpeed() {
    speed++;
    if(speed > 5) speed = 0;
    updateUI();
}

int main() {
    updateUI();
    increaseSpeed();
    increaseSpeed();
}

Controls fan speed using PWM steps.

#include "mbed.h"

DigitalOut led1(LED1);
DigitalOut led2(LED2);

void updateLEDs(bool state1, bool state2) {
    led1 = state1;
    led2 = state2;
    printf("LED1: %s, LED2: %s\n", state1 ? "ON" : "OFF", state2 ? "ON" : "OFF");
}

int main() {
    updateLEDs(true, false);
    updateLEDs(false, true);
}

Alternates two LEDs on and off.

#include "mbed.h"

int humidity = 60;
bool alert = false;

void updateUI() {
    printf("Humidity: %d\n", humidity);
    if(alert) printf("Alert: High Humidity!\n");
}

void readSensor() {
    humidity += 5;
    alert = humidity > 70;
    updateUI();
}

int main() {
    updateUI();
    readSensor();
    readSensor();
}

Simulates a humidity sensor with alert threshold.

#include "mbed.h"

DigitalOut led(LED1);

void blinkPattern() {
    led = !led;
    printf("LED is %s\n", led ? "ON" : "OFF");
}

int main() {
    blinkPattern();
    blinkPattern();
    blinkPattern();
}

Blink an LED in a simple on/off pattern.