Get ESP32 to Auto Reconnect to Bluetooth from Arduino Sketch

How to get ESP32 to auto reconnect to Bluetooth from Arduino sketch?

In this post I show you how to get the ESP32 to automatically reconnect to your Bluetooth from an Arduino sketch.

Introduction

ESP8266 is a popular WiFi module that allows you to connect to the internet wirelessly. Arduino is a popular microcontroller platform that allows you to create electronic projects.

ESP8266 can be used with Arduino as a WiFi module. However, one issue you may encounter is that the ESP8266 may not automatically reconnect to the Arduino’s Bluetooth connection if it is disconnected.

There are some ways you can solve this problem. One way is to add a line of code to your Arduino sketch that will force the ESP8266 to reconnect to the Bluetooth connection if it is disconnected. Another way is to use a special software library designed for ESP8266 that will handle the reconnection automatically.

Overall, using ESP8266 with Arduino can be a great way to add WiFi connectivity to your project. However, you may need to take some extra steps to make sure the ESP8266 automatically reconnects to the Arduino’s Bluetooth connection if it is disconnected.

How Bluetooth Works

1. How Bluetooth Works

Bluetooth is a short-range wireless technology that allows two devices to connect to each other. It uses radio waves to communicate, so it doesn’t require a physical connection like a USB cable.

2. How to Use Bluetooth with Arduino

You can use Bluetooth to connect your Arduino to other devices. For example, you can connect your Arduino to a smartphone or computer and use it to control the device. You can also use Bluetooth to transfer data between two devices.

3. How to Set up Bluetooth on Your Arduino

To use Bluetooth with your Arduino, you’ll need a Bluetooth module. There are many different types of Bluetooth modules available, but we recommend the HC-05 module. This module is easy to use and is compatible with most Arduino boards.

Once you have your Bluetooth module, you’ll need to connect it to your Arduino board. The HC-05 module uses serial communication, so you’ll need to connect it to the Rx and Tx pins on your Arduino board. Check the documentation for your specific module for more information on how to do this.

The ESP32 Bluefruit LE Interrupts

The Arduino sketch for this project is available here.

This project demonstrates how to use the Esp32 Bluefruit LE Interrupts feature to automatically reconnect to a Bluetooth device when it becomes disconnected.

In this example, we will use an Esp32 board with a BLE module to connect to a nearby Bluetooth device. If the connection is lost, the Esp32 will automatically reconnect to the device.

To test this sketch, you will need two Esp32 boards, one with the BLE module and one without. The BLE module should be set up as a peripheral device and the other board should be set up as a central device.

When the two boards are within range of each other, the BLE module will connect to the central device. Once the connection is established, you can move away from the central device and the connection will remain intact. However, if you move too far away from the central device, the connection will be lost.

Once the connection is lost, the BLE module on the peripheral board will automatically start scanning for nearby devices. When it finds the central device, it will automatically reconnect to it.

You can test this sketch by moving away from your central device.

What is an Arduino Sketch?

An Arduino sketch is a program that is written in the Arduino programming language and uploaded to an Arduino board. This program can be used to control the board and its attached peripherals.

Arduino sketches can be used to control various types of Bluetooth devices, including ESP32 boards. The ESP32 is a low-cost, low-power microcontroller with built-in WiFi and Bluetooth functionality. It can be used to create a variety of IoT applications.

To get an ESP32 board to auto-reconnect to a Bluetooth device, you can use the following code in your Arduino sketch:

 void setup()   
 {  
  Serial.begin(115200);  
  Serial.println("ESP32 Auto Reconnect Sketch");  
   
  //Initialize the ESP32 module  
  WiFi.begin();  
   
  //Wait for the Wi-Fi to connect  
  while (WiFi.waitForConnectResult() != WL_CONNECTED) {  
  Serial.println("WiFi Connected Failed! Retrying...");  
  delay(5000);  
  }
 }

An Arduino sketch is a piece of code written in the Arduino programming language. This code can be used to control an Arduino board and perform various tasks.

One of the most common uses for an Arduino sketch is to control a device via Bluetooth. This can be done by using the Arduino Bluetooth library. This library allows an Arduino board to connect to a Bluetooth device and exchange data with it.

To use the Arduino Bluetooth library, you first need to include it in your sketch. You can do this by adding the following line of code at the beginning of your sketch:

 #include <ArduinoBluetooth.h>

Once the library is included, you can then call various functions from it to connect to a Bluetooth device and exchange data with it.

Why does the ESP32 Auto Reconnect to bluetooth?

The ESP32 can automatically reconnect to a Bluetooth device after a connection has been lost. This is useful for devices that are not always in range, such as a fitness tracker or a wireless headphones.

When the ESP32 connects to a Bluetooth device, it will automatically reconnect to that device if the connection is lost. This feature is turned on by default, but you can turn it off by going into the Arduino sketch and disabling the AUTO_RECONNECT flag.

The ESP32 will also try to reconnect to a Bluetooth device if it is powered off and then turned back on. This is useful for devices that are turned off frequently, such as a power outage or when you go to sleep at night.

You can also force the ESP32 to disconnect from a Bluetooth device by calling the disconnect() function. This can be useful if you want to connect to another device or if you want to save battery life.

How do I keep my ESP32 to auto reconnect to Bluetooth?

If your esp32 is configured to connect to a Bluetooth device, it will automatically try to reconnect to that device if the connection is lost. This can be useful if you want to maintain a constant connection between your esp32 and a Bluetooth device, for example.

To configure your esp32 to auto reconnect to a Bluetooth device, you will need to add the following line of code to your Arduino sketch:

 esp_bt_gap_set_scan_mode(ESP_BT_SCAN_MODE_CONNECTABLE_DISCOVERABLE);

This will ensure that your esp32 will always try to reconnect to a previously paired Bluetooth device if the connection is lost.

Get esp32 to auto reconnect to Bluetooth from Arduino Sketch