Sample Project 1 – Traffic Light
1 x Arduino Uno R3
3 x LED (any color)
3 x Resistor
Jumper Wires
1 x Breadboard
1 x Ultrasonic Sensor HC-04
Wiring Guide:
- Connect the anode (longer leg) of each LED to a separate digital pin on the Arduino (pins 2, 3, and 4).
- Connect the cathode (shorter leg) of each LED to a separate resistor.
- Connect the other end of each resistor to the ground (GND) on the Arduino.
- Connect the ground (GND) of the Arduino to the ground rail of the breadboard.
- Connect the power (5V) of the Arduino to the power rail of the breadboard.
Code:
// Pin definitions
const int redPin = 2;
const int yellowPin = 3;
const int greenPin = 4;
// Time delays in milliseconds
const int redDelay = 5000; // 5 seconds for red
const int yellowDelay = 2000; // 2 seconds for yellow
const int greenDelay = 5000; // 5 seconds for green
void setup() {
// Set the LED pins as OUTPUT
pinMode(redPin, OUTPUT);
pinMode(yellowPin, OUTPUT);
pinMode(greenPin, OUTPUT);
}
void loop() {
// Red light
digitalWrite(redPin, HIGH);
digitalWrite(yellowPin, LOW);
digitalWrite(greenPin, LOW);
delay(redDelay);
// Yellow light
digitalWrite(yellowPin, HIGH);
delay(yellowDelay);
// Green light
digitalWrite(redPin, LOW);
digitalWrite(yellowPin, LOW);
digitalWrite(greenPin, HIGH);
delay(greenDelay);
}
Sample Project 2 – Buzzer Music
1 x Arduino Uno R3
1 x Female to Male Jumper Wire
1 x Active Buzzer
Wiring Guide:
- Connect one leg of the buzzer to digital pin 9 on the Arduino.
- Connect the other leg of the buzzer to the ground (GND) on the Arduino using a jumper wire
Code:
#include “pitches.h”
// Define the pins
#define BUZZER_PIN 9
// Define the simple melody notes and durations
int melody[] = {
NOTE_C4, NOTE_D4, NOTE_E4, NOTE_F4, NOTE_G4, NOTE_A4, NOTE_B4, NOTE_C5
};
// Define the corresponding durations
int noteDurations[] = {
4, 4, 4, 4, 4, 4, 4, 4
};
void setup() {
// Set the BUZZER_PIN as an OUTPUT
pinMode(BUZZER_PIN, OUTPUT);
}
void loop() {
// Play the simple melody
playMelody();
}
void playMelody() {
for (int i = 0; i < sizeof(melody) / sizeof(melody[0]); i++) {
int noteDuration = 1000 / noteDurations[i];
tone(BUZZER_PIN, melody[i], noteDuration);
delay(noteDuration * 1.30); // add a small delay to separate the notes
noTone(BUZZER_PIN); // stop the tone playing
}
delay(1000); // pause between melodies
}
Sample Project 3 – Temperature and Humidity Monitor
1 x Arduino Uno R3
Jumper Wires
1 x LCD1602 with I2C module
1 x Breadboard
Wiring Guide:
- Connect the I2C module to the Arduino board:
- Connect the SDA pin on the I2C module to the A4 pin on the Arduino.
- Connect the SCL pin on the I2C module to the A5 pin on the Arduino.
- Connect VCC on the I2C module to the 5V pin on the Arduino (or breadboard).
- Connect GND on the I2C module to the GND pin on the Arduino (or breadboard).
- Connect DHT11 to the Arduino Board:
- Connect the VCC pin of the DHT11 to 5V on the Arduino (or breadboard).
- Connect the data pin of the DHT11 to a digital pin 2 on the Arduino.
- Connect the GND pin of the DHT11 to GND on the Arduino (or breadboard).
Code:
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <DHT.h>
#define DHTPIN 2 // DHT11 data pin connected to D2
#define DHTTYPE DHT11 // DHT11 sensor type
DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2); // I2C address 0x27, 16 columns and 2 rows
void setup() {
Serial.begin(9600);
lcd.begin(16, 2);
lcd.backlight();
dht.begin(); // Initialize the DHT sensor
delay(2000); // Allow time for sensor to stabilize
}
void loop() {
float temperature = dht.readTemperature(); // Reading temperature from DHT sensor
float humidity = dht.readHumidity(); // Reading humidity from DHT sensor
lcd.clear(); // Clear the LCD display
lcd.setCursor(0, 0);
lcd.print(“Temp: “);
lcd.print(temperature, 1); // Display temperature with one decimal place
lcd.print(” C”);
lcd.setCursor(0, 1);
lcd.print(“Humidity: “);
lcd.print(humidity, 1); // Display humidity with one decimal place
lcd.print(” %”);
delay(1000); // polling (1 second)
}
Sample Project 4 – Buzzer Sonar
1 x Arduino Uno R3
Jumper Wires
1 x Buzzer
1 x HC-06
Wiring Guide:
- Connect the HC-SR04 Ultrasonic Sensor:
- Connect the VCC pin of the sensor to the 5V pin on the Arduino (or breadboard).
- Connect the GND pin of the sensor to the GND pin on the Arduino (or breadboard).
- Connect the TRIG pin of the sensor to digital pin 9 on the Arduino.
- Connect the ECHO pin of the sensor to digital pin 10 on the Arduino.
- Connect the Buzzer:
- Connect the positive (longer) leg of the buzzer to digital pin 8 on the Arduino.
- Connect the negative (shorter) leg of the buzzer to the GND pin on the Arduino (or breadboard).
Code:
#define TRIG_PIN 9
#define ECHO_PIN 10
#define BUZZER_PIN 8
void setup() {
Serial.begin(9600);
pinMode(TRIG_PIN, OUTPUT);
pinMode(ECHO_PIN, INPUT);
pinMode(BUZZER_PIN, OUTPUT);
}
void loop() {
long duration, distance;
// Clear the trigger pin
digitalWrite(TRIG_PIN, LOW);
delayMicroseconds(2);
// Send a 10 microsecond pulse to the trigger pin
digitalWrite(TRIG_PIN, HIGH);
delayMicroseconds(10);
digitalWrite(TRIG_PIN, LOW);
// Measure the time taken for the pulse to return
duration = pulseIn(ECHO_PIN, HIGH);
// Calculate the distance in centimeters
distance = (duration / 2) / 29.1;
// Print the distance to the Serial Monitor
Serial.print(“Distance: “);
Serial.print(distance);
Serial.println(” cm”);
// Set a longer delay if distance is above 60
int beepDelay = (distance > 60) ? 1000 : map(distance, 2, 60, 50, 500);
// Set a shorter beep duration
int beepDuration = 50;
// Control the buzzer based on the distance
tone(BUZZER_PIN, 1000, beepDuration); // Constant frequency for the example
delay(beepDuration);
// Stop the buzzer after the beep duration
noTone(BUZZER_PIN);
// Add an additional delay for distances above 60
if (distance > 60) {
delay(1000); // 1-second delay between beeps
} else {
delay(beepDelay); // Delay between beeps
}
}
