ESP32 As Bluetooth Keyboard - Electronics Club, IIT Madras

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ESP32 as Bluetooth Keyboard

Description:

• ESP32 has BLE support thus it can be used as Bluetooth Keyboard with open source library
• Compatible with Windows,Linux,Android,MacOSX,iOS

Concept:

Making use of the Blutooth Capability of ESP32 board,we are going to send keystrokes to the device we want to. Various use cases are possible:

• Automating any set of actions
• Taking a photo with a hand trigger
• and many more

Parts Required:

• ESP32 Board
• Push buttons
• Jumper wires

Schematics:

Instructions:

1. Load Arduino IDE
2. Install the library from here (https://github.com/T-vK/ESP32-BLE-Keyboard/releases)
3. Add the .ZIP library from the sketch menu
4. Make the connections according to the schematic
5. Try out the below codes:

Space bar button

• Upload the below code
• Connect with PC using Bluetooth
• Open "chrome://dino" and start playing

//D13 Button pin //3.3V Connected to the other leg of the button #include <BleKeyboard.h> //Set the name of the bluetooth keyboard (that shows up in the bluetooth menu of your device) BleKeyboard bleKeyboard("ESP_KEYBOARD"); const int buttonPin = 13; //Set the old button state to be LOW/false; which means not pressed boolean oldPinState = LOW; void setup() { //Start the Serial communication (with the computer at 115200 bits per second) Serial.begin(115200); //Send this message to the computer Serial.println("Starting BLE work!"); //Begin the BLE keyboard/start advertising the keyboard (so phones can find it) bleKeyboard.begin(); //Make the button pin an INPUT_PULLDOWN pin, which means that it is normally LOW, untill it is pressed/ connected to the 3.3V pinMode(buttonPin, INPUT_PULLDOWN); } void loop() { if (bleKeyboard.isConnected()) { //if the keyboard is connected to a device if (digitalRead(buttonPin) == HIGH) { //If the button pin is pressed (since it is pulled down, it is pressed when it is high) if (oldPinState == LOW) { //if the old Pin state was LOW and the button pin is HIGH than... //send the spacebar bleKeyboard.print(" "); } oldPinState = HIGH; } else { oldPinState = LOW; } } delay(10); }

Play/Pause button

• Upload the below code
• Connect with Phone using Bluetooth
• Play your favourite music playlist,and now you can play pause the song using the ESP_keyboard

#include <BleKeyboard.h> //Set the name of the bluetooth keyboard (that shows up in the bluetooth menu of your device) BleKeyboard bleKeyboard("ESP_KEYBOARD"); const int buttonPin = 13; //Set the old button state to be LOW/false; which means not pressed boolean oldPinState = LOW; int state = 0; void setup() { //Start the Serial communication (with the computer at 115200 bits per second) Serial.begin(115200); //Send this message to the computer Serial.println("Starting BLE work!"); //Begin the BLE keyboard/start advertising the keyboard (so phones can find it) bleKeyboard.begin(); //Make the button pin an INPUT_PULLDOWN pin, which means that it is normally LOW, untill it is pressed/ connected to the 3.3V pinMode(buttonPin, INPUT_PULLDOWN); } void loop() { if (bleKeyboard.isConnected()) { if (state == 0 && digitalRead(buttonPin) == HIGH) { state = 1; bleKeyboard.write(KEY_MEDIA_PLAY_PAUSE); } if (state == 1 && digitalRead(buttonPin) == LOW) { state = 0; } } delay(10); }