Arduino code basics

You don't know how to start coding in Arduino IDE, or just want to learn the basics of arduino programming?
This page is for you!

Download the Arduino IDE

To program the arduino, you need a software called Arduino IDE.

You can download it from the arduino official website. I recommend downloading the latest version.

Getting started

Before you begin coding, there are a few steps you need to complete.

First of all choose your board:

  • Open Arduino IDE
  • Click "Tools"
  • Then "Boards", and select your board

    • Now choose the port:

  • Click "Tools"
  • Then click "Port", and select the port

    • Arduino IDE

    Start coding

    Now let's start programming! (I mean, soon)

    When you open the code editor, you probably see this:

    Arduino IDE

    What does it mean?

  • void: It is a type of function, which doesn't have a return value. So when we run this, it doesn't give us any value(integer, string).
  • setup: This is the name of the function. It runs once, after each powerup of the Arduino board. We usually write things into like: pinMode() or Serial.begin()
  • loop: This funtion runs continuously from the power on to the off.

    • Blinking LED

    We haven't done anything yet, so let's load some example code! 😊

  • Click "File" in the IDE
  • Then choose "Examples", "Basics", "Blink"
  • Last but not least upload the code by clicking on the arrow icon

    • Arduino IDE

    Hurray! The little LED on the arduino is blinking!

    So what does the code we uploaded mean?

  • void setup(): We already know this.
  • pinMode(LED_BUILTIN, OUTPUT): This is a function to initialize a digital pin as an input or output. It has 2 parameters: pin(LED_BUILTIN; 1; 2; 3 etc.) and mode(INPUT; OUTPUT).
  • void loop(): We already know this too.
  • digitalWrite(LED_BUILTIN, HIGH): This function writes a value to a digital pin. So voltage of the pin will be set to 5V (or 3V) for HIGH, and 0V for LOW. It needs 2 parameters: pin and value(LOW, HIGH).
  • delay(1000): This pauses all processes in the code. It has one parameter: time (in ms).

    • Variables

    The variables in the Arduino IDE are similar to the C++ and C variables.

    We use:

  • int for integers
  • char for characters and strings
  • float for floating-point numbers
  • double for double precision floating point number (it is the same as float on AVR arduino boards)
  • bool for represent logical values(true or false)

    • Functions

    Here are some frequently used functions:

  • pinMode(): Configures a digital pin as input or an output
  • digitalWrite(): Writes a value to a digital pin (LOW or HIGH)
  • digitalRead(): Reads a value from a digital pin(LOW, HIGH)
  • analogWrite(): Writes an analog value to a pin(0-255)
  • analogRead(): Reads the value from an analog pin
  • delay(): Pauses the program for a specific time(in ms)
  • random(): Generates a random number
  • Serial.begin(): Sets the data rate in bits per second data communication
  • Serial.print(): Prints data to the serial port, which you can view on the serial monitor