How to Use an ESP8266 as a TV Remote

The ESP8266 is a powerful microcontroller with built-in Wi-Fi capabilities, making it an excellent choice for IoT projects. In this tutorial, we will use an ESP8266 to function as a TV remote, sending infrared (IR) signals to control a television.

Components Required

• ESP8266 (NodeMCU or Wemos D1 Mini)
• IR LED
• 220Ω Resistor
• NPN Transistor (e.g., 2N2222)
• Jumper wires
• Breadboard
• TV remote (for learning IR signals)
• IR Receiver module (optional, for learning mode)

Step 1: Install Necessary Libraries

To send IR signals using the ESP8266, install the IRremoteESP8266 library in the Arduino IDE:

1. Open Arduino IDE.
2. Go to Sketch > Include Library > Manage Libraries.
3. Search for IRremoteESP8266 and install it.

Step 2: Circuit Diagram

Connect the components as follows:

• Connect the IR LED’s anode (+) to 3.3V.
• Connect the cathode (-) to the collector of the transistor.
• Connect the emitter of the transistor to GND.
• Connect a 220Ω resistor from the ESP8266 GPIO pin (e.g., D5/GPIO14) to the base of the transistor.

If using an IR receiver for learning mode:

• Connect VCC to 3.3V.
• Connect GND to GND.
• Connect Signal pin to D4/GPIO2.

Step 3: Capture IR Codes (Optional)

If you don’t know the IR codes for your TV, you can capture them using an IR receiver module. Use this code to read IR signals:

#include <IRrecv.h>
#include <IRremoteESP8266.h>
#include <IRutils.h>

const uint16_t RECV_PIN = 2; // D4
IRrecv irrecv(RECV_PIN);
decode_results results;

void setup() {
  Serial.begin(115200);
  irrecv.enableIRIn();
}

void loop() {
  if (irrecv.decode(&results)) {
    Serial.println(results.value, HEX);
    irrecv.resume();
  }
}

Upload this sketch and open the Serial Monitor. Press a button on your TV remote, and it will display the corresponding IR hex code.

Step 4: Sending IR Signals

Once you have the required IR hex codes, use the following code to transmit them using the ESP8266:

#include <IRsend.h>
#include <IRremoteESP8266.h>

const uint16_t IR_LED = 14; // D5
IRsend irsend(IR_LED);

void setup() {
  irsend.begin();
}

void loop() {
  irsend.sendNEC(0x20DF10EF, 32); // Replace with your TV's IR code
  delay(2000);
}

This example sends an NEC protocol IR signal every 2 seconds. Replace 0x20DF10EF with the correct IR hex code for your TV button.

Step 5: Adding Wi-Fi Control (Optional)

To control your TV over Wi-Fi, you can set up a simple web server on the ESP8266 and trigger IR signals via a web interface. Use the ESP8266WebServer library to create buttons for different TV functions.

Example Web Server Code:

#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <IRsend.h>

const char* ssid = "Your_SSID";
const char* password = "Your_PASSWORD";
ESP8266WebServer server(80);
IRsend irsend(14);

void handlePower() {
  irsend.sendNEC(0x20DF10EF, 32);
  server.send(200, "text/plain", "Power button pressed");
}

void setup() {
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
  }
  irsend.begin();
  server.on("/power", handlePower);
  server.begin();
}

void loop() {
  server.handleClient();
}

Access http://ESP_IP/power in your browser to turn the TV on or off remotely.

Conclusion

Using an ESP8266 as a TV remote allows for smart control via IR signals and even Wi-Fi. This project can be extended to control multiple appliances using different IR codes and voice assistants like Alexa or Google Assistant. Experiment with different IR protocols and enhance your home automation setup!