Lesson 1

Introduction to Arduino and the Development Environment

Before we dive into the code, make sure you have the Arduino IDE (Integrated Development Environment) installed. You can download it from the official Arduino website.

Once installed, here are a few key concepts:

Arduino Board: This is the hardware that runs your code. Popular boards include the Arduino Uno, Arduino Nano, etc.

Sketch: This is the name for an Arduino program. It’s written in C/C++.

IDE: The software used to write and upload your code to the Arduino board.

Key Components of an Arduino Sketch

An Arduino sketch typically consists of two main parts:

Setup function (setup()): This function runs once when the board is powered up or reset. It's where you put initialization code.

Loop function (loop()): This function runs repeatedly, and it contains the code that you want to execute continuously.

Here’s a basic sketch:

void setup() { // Initialize serial communication at a baud rate of 9600: Serial.begin(9600); } void loop() { // Print "Hello, Arduino!" to the Serial Monitor Serial.println("Hello, Arduino!"); delay(1000); // Wait for 1 second (1000 milliseconds) }

Steps to Run Your First Program:

Open the Arduino IDE.

Select your board from the "Tools" menu (e.g., Arduino Uno).

Select your port under the "Tools" menu (the port where your Arduino is connected).

Copy and paste the code above into the IDE.

Click the Upload button to upload the code to your Arduino board.

Open the Serial Monitor from the Tools menu to see the output.

Explanation:

Serial.begin(9600) initializes serial communication at a speed of 9600 bits per second (baud rate).

Serial.println("Hello, Arduino!") sends a string to the Serial Monitor.

delay(1000) pauses the program for 1000 milliseconds (1 second).

This is just the beginning!

Lesson 2

Working with Digital Pins

In this lesson, we will learn how to control and read values from digital pins on the Arduino board. Digital pins can either read or write HIGH (1) or LOW (0) values. You can connect devices like LEDs, switches, and sensors to these pins.

Controlling an LED (Output)

In this example, we'll turn an LED on and off. Here's a simple sketch:

int ledPin = 13; // Pin 13 is usually connected to the built-in LED on the Arduino void setup() { pinMode(ledPin, OUTPUT); // Set pin 13 as an output pin } void loop() { digitalWrite(ledPin, HIGH); // Turn the LED on delay(1000); // Wait for 1 second digitalWrite(ledPin, LOW); // Turn the LED off delay(1000); // Wait for 1 second }

Key Points:

pinMode(pin, mode): This sets the mode of a pin. OUTPUT means the pin will be used to control a device like an LED, while INPUT is used for reading values.

digitalWrite(pin, value): This sends either a HIGH (1) or LOW (0) signal to the pin. For an LED, HIGH turns it on and LOW turns it off.

delay(ms): Pauses the program for the specified time (in milliseconds).

Reading a Button (Input)

Now let’s learn how to read the state of a button. We'll use a button connected to pin 2 to control the LED. Here’s the code for that:

int buttonPin = 2; // Pin connected to the button int ledPin = 13; // Pin connected to the LED int buttonState = 0; // Variable to store the button state void setup() { pinMode(buttonPin, INPUT); // Set the button pin as input pinMode(ledPin, OUTPUT); // Set the LED pin as output } void loop() { buttonState = digitalRead(buttonPin); // Read the state of the button if (buttonState == HIGH) { // Button is pressed digitalWrite(ledPin, HIGH); // Turn the LED on } else { digitalWrite(ledPin, LOW); // Turn the LED off } }

Key Points:

digitalRead(pin): Reads the value (HIGH or LOW) of a digital input pin (button).

When the button is pressed, it sends a HIGH signal, which turns the LED on.

Your task:

Try running the LED blink code from the first example and observe how the LED turns on and off.

Connect a button to your Arduino and modify the code to control the LED based on the button state.

Lesson 3

Control Structures in Arduino (C++)

In this lesson, we’ll explore control structures in Arduino programming using C++.

What Are Control Structures?

Control structures determine the flow of execution in a program. Common types in Arduino include:

Conditional statements (if, else, else if, switch)

Loops (for, while, do-while)

1. Conditional Statements

if Statement

Executes a block of code if a condition is true.

Example:

int sensorValue = analogRead(A0); // Read a value from pin A0 void setup() { Serial.begin(9600); // Start Serial communication } void loop() { if (sensorValue > 500) { Serial.println("High value detected!"); // Print if value is above 500 } }

if-else Statement

Executes one block of code if the condition is true, otherwise executes another.

Example:

int sensorValue = analogRead(A0); void setup() { Serial.begin(9600); } void loop() { if (sensorValue > 500) { Serial.println("Value is high."); } else { Serial.println("Value is low."); } }

else if Statement

Allows for multiple conditions to be checked.

Example:

int sensorValue = analogRead(A0); void setup() { Serial.begin(9600); } void loop() { if (sensorValue > 700) { Serial.println("Very high value!"); } else if (sensorValue > 500) { Serial.println("Moderate value."); } else { Serial.println("Low value."); } }

switch Statement

Useful for evaluating a single variable against multiple cases.

Example:

int buttonState = digitalRead(2); // Read digital pin 2 void setup() { pinMode(2, INPUT); // Set pin 2 as input Serial.begin(9600); } void loop() { switch (buttonState) { case HIGH: Serial.println("Button Pressed"); break; case LOW: Serial.println("Button Released"); break; default: Serial.println("Unknown State"); } }

2. Loops

for Loop

Repeats a block of code a specified number of times.

Example:

void setup() { Serial.begin(9600); } void loop() { for (int i = 0; i < 10; i++) { Serial.println(i); // Print numbers 0 to 9 delay(500); // Wait 500ms between each number } }

while Loop

Repeats a block of code as long as the condition is true

.

Example:

int count = 0; void setup() { Serial.begin(9600); } void loop() { while (count < 5) { Serial.println(count); count++; delay(500); } }

do-while Loop

Executes the block of code once before checking the condition.

Example:

int count = 0; void setup() { Serial.begin(9600); } void loop() { do { Serial.println(count); count++; delay(500); } while (count < 5); }

Practical Example

Let’s combine conditionals and loops in a simple LED control program:

LED Control Based on Button Presses

int buttonPin = 2; // Button connected to pin 2 int ledPin = 13; // LED connected to pin 13 void setup() { pinMode(buttonPin, INPUT); // Set button pin as input pinMode(ledPin, OUTPUT); // Set LED pin as output Serial.begin(9600); } void loop() { int buttonState = digitalRead(buttonPin); if (buttonState == HIGH) { digitalWrite(ledPin, HIGH); // Turn LED on Serial.println("Button Pressed: LED ON"); } else { digitalWrite(ledPin, LOW); // Turn LED off Serial.println("Button Released: LED OFF"); } delay(100); // Add a small delay to debounce }

Key Points to Remember:

Use if, else, and else if for decision-making.

Use switch for cases where a variable is compared against multiple values.

Use loops (for, while, do-while) to repeat tasks.

Always test with simple components like LEDs and buttons to observe results.