Receiving commands over Bluetooth in Arduino - Mini Project: Build & Apply

Receiving commands over Bluetooth

📖 Scenario: You have a small robot controlled by an Arduino board. You want to send simple commands from your phone using Bluetooth to make the robot move.

🎯 Goal: Build a program that receives commands over Bluetooth and prints the received command to the Serial Monitor.

📋 What You'll Learn

Create a Bluetooth serial connection using SoftwareSerial on pins 10 and 11

Set up the serial communication at 9600 baud rate

Read incoming Bluetooth data as characters

Store the received command in a variable called command

Print the received command to the Serial Monitor

💡 Why This Matters

🌍 Real World

Bluetooth communication is common in remote control devices, home automation, and wireless sensors.

💼 Career

Understanding how to receive and process Bluetooth commands is useful for embedded systems and IoT development jobs.

1

Set up Bluetooth serial communication

Create a SoftwareSerial object called bluetooth using pins 10 for RX and 11 for TX.

Arduino

# Create a SoftwareSerial object called bluetooth on pins 10 (RX) and 11 (TX)
// Your code here

Need a hint?

Use SoftwareSerial bluetooth(10, 11); to create the Bluetooth serial object.

2

Initialize serial communications

In the setup() function, start the hardware serial communication with Serial.begin(9600); and the Bluetooth serial communication with bluetooth.begin(9600);.

Arduino

#include 

SoftwareSerial bluetooth(10, 11); // RX, TX

void setup() {
  // Start serial communication at 9600 baud
  // Your code here
}

void loop() {
  // Nothing here yet
}

Need a hint?

Use Serial.begin(9600); and bluetooth.begin(9600); inside setup().

3

Read incoming Bluetooth commands

In the loop() function, check if bluetooth.available() is greater than zero. If yes, read one character from bluetooth.read() and store it in a variable called command of type char.

Arduino

#include 

SoftwareSerial bluetooth(10, 11); // RX, TX

void setup() {
  Serial.begin(9600);
  bluetooth.begin(9600);
}

void loop() {
  // Check if data is available from bluetooth
  // Your code here
}

Need a hint?

Use if (bluetooth.available() > 0) and inside it, char command = bluetooth.read();.

4

Print the received command

Inside the if block in loop(), add a line to print the command variable to the Serial Monitor using Serial.print(command);.

Arduino

#include 

SoftwareSerial bluetooth(10, 11); // RX, TX

void setup() {
  Serial.begin(9600);
  bluetooth.begin(9600);
}

void loop() {
  if (bluetooth.available() > 0) {
    char command = bluetooth.read();
    // Print the command to Serial Monitor
    // Your code here
  }
}

Need a hint?

Use Serial.print(command); to show the received character.