How Do I Print a String Data Type in Arduino?


Scott Campbell

How Do I Print a String Data Type in Arduino?

Printing a string data type in Arduino is a fundamental skill that every Arduino programmer must learn. Strings are used to store and manipulate text-based data, so being able to print them is essential for debugging, displaying information, and communicating with the user.

Using the Serial Monitor

The simplest way to print a string in Arduino is by using the Serial Monitor. The Serial Monitor is a powerful tool that allows you to send and receive data between your Arduino board and your computer.

To print a string, you need to use the Serial.print() or Serial.println() function. The difference between these two functions is that Serial.print() prints the text without adding a new line at the end, while Serial.println() adds a new line after printing.

Here’s an example of how to print a string using the Serial Monitor:

void setup() {
  // Initialize the serial communication

void loop() {
  // Define a string
  String myString = "Hello World!";

  // Print the string

  // Wait for some time

In this example, we first initialize the serial communication by calling Serial.begin(). Then, inside the loop() function, we define a string variable called myString.

We assign it the value “Hello World!”. Finally, we use Serial.println(myString) to print the string to the Serial Monitor.

Using LCD Displays

If you have an LCD display connected to your Arduino, you can also print strings on it. LCD displays are commonly used to show information in projects where a visual output is required.

To print a string on an LCD display, you need to include the appropriate library for your specific display model. Most Arduino libraries for LCD displays provide functions like print() or println() to print text.

Here’s an example using the LiquidCrystal library and a 16×2 LCD display:

#include <LiquidCrystal.h>

// Initialize the LCD object
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

void setup() {
  // Set up the number of columns and rows on the LCD
  lcd.begin(16, 2);
  // Print a string on the LCD
  lcd.print("Hello World!");

void loop() {
  // Code for other functionalities

In this example, we first include the LiquidCrystal library. We then create an object called lcd using the necessary pin numbers for our specific display model. Inside the setup() function, we call lcd.begin() to initialize the display with its dimensions.

Finally, we use lcd.print() to print “Hello World!” on the LCD.

Incorporating String Variables in Strings

Sometimes you may need to print a combination of fixed text and variable values in a single string. Arduino provides several ways to achieve this.

One common approach is using the String concatenation operator (+) to combine strings. Here’s an example:

void loop() {
int sensorValue = analogRead(A0);

// Construct a string with a variable value
String message = “Sensor value: ” + String(sensorValue);

// Print the string

// Wait for some time

In this example, we read an analog value from pin A0 and store it in the sensorValue variable. Then, we construct a string called message by concatenating the fixed text “Sensor value: ” with the value of sensorValue.

Finally, we print the message using Serial.println().

In Summary

  • To print a string data type in Arduino, you can use either the Serial Monitor or an LCD display.
  • In the Serial Monitor, use Serial.
  • If you have an LCD display, include the appropriate library and use its provided functions.
  • You can also incorporate variable values into strings using concatenation.

By mastering this skill, you’ll be able to effectively display text-based information in your Arduino projects and improve your debugging capabilities. Happy coding!