Arduino Masterclass - Lesson 3: How to create Arduino Programs

Learn how Arduino programs work

👋 Welcome to Arduino programming! This lesson will teach you how Arduino programs work. You can apply this to 100% of your programs later.

💡How Arduino Programs Run?

Every Arduino program has two essential functions: setup() runs once when the board starts, and loop() runs continuously forever. Understanding this flow is key to programming Arduino.

Arduino Program Flow

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setup() { // your code here }
loop() { // your code here }
Reset Button
Loop count: 0
Status: Waiting to start

Understanding setup() and loop()

🔧setup() Function

Runs ONCE when Arduino starts or resets. Use it to initialize pins, serial communication, and variables.

🔄loop() Function

Runs CONTINUOUSLY in an infinite loop. This is where your main program logic goes.

🔄Reset Button

Pressing the reset button restarts the Arduino, running setup() again followed by loop().

💡Official Arduino Programming Language Documentation

This is considered the bible for looking up everything about the Arduino programming language. It's organized into three main categories:

CategoryDescription
📐Structure
Program structure including setup(), loop(), and I/O pin control, ...
⚙️Functions
Built-in functions like digitalWrite(), digitalRead(), delay(), and many more
📦Variables
Data types, constants, and variable declarations

📚 The bible can be found here: Arduino Language Reference

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💡 Don't be scared! The documentation is very friendly with clear examples and short, easy-to-read explanations.

How to use the documentation:

  • You don't need to read everything - use it like a directory. When you're reading a program and unsure about a term, look it up there.
  • If you still don't understand something, ask ChatGPT to explain it in simpler terms.
  • It's always up-to-date and the only source of truth for accurate and exact Arduino information.