ESP8266 NodeMCU Web Server: Control a DC Motor (Arduino IDE)

Introduction

The ESP8266 NodeMCU is a popular Wi-Fi-enabled microcontroller, well-known for its low cost and versatility in Internet of Things (IoT) applications. One powerful application is building a web server to remotely control a DC motor. This capability opens the door for projects like home automation, robotics, and remote-controlled systems.

In this tutorial, you’ll learn how to set up a web interface using the ESP8266 NodeMCU to control a DC motor‘s direction and speed. We will use a motor driver, design a responsive web server, and explore real-world applications. For a comprehensive guide on this subject, refer to this ESP8266 motor control tutorial. Also, this resource explains PWM-based speed control.

Understanding the Components

ESP8266 NodeMCU

Integrated Wi-Fi and TCP/IP stack
Multiple GPIO pins for output control
Supports PWM (Pulse Width Modulation) for speed control

DC Motors

Converts electrical energy into mechanical motion
Commonly used in robotics and automation
Controlled through voltage polarity and power

L298N Motor Driver

Dual H-Bridge driver for controlling direction
Provides sufficient current to run motors safely
Connects directly to the ESP8266 and motor

Setting Up the Development Environment

Installing Arduino IDE

Download from the official Arduino website
Install and open the IDE

Adding ESP8266 Board to Arduino IDE

Go to File > Preferences > Additional Board Manager URLs
Add: http://arduino.esp8266.com/stable/package_esp8266com_index.json
Install the ESP8266 board via Board Manager

Required Libraries

ESPAsyncWebServer
ESPAsyncTCP
Install through Library Manager or GitHub repositories

Circuit Diagram and Hardware Connections

ESP8266 NodeMCU Web Server Control a DC Motor (Arduino IDE)

Connect IN1 and IN2 of L298N to two GPIO pins on ESP8266
Connect EN1 (Enable pin) to a PWM-capable GPIO
Power L298N with external 9V battery or power adapter
Ensure motor ground, L298N ground, and ESP8266 ground are connected

Pin Example:

GPIO5 -> IN1
GPIO4 -> IN2
GPIO0 (PWM) -> ENA

Writing the Arduino Sketch

Initializing Libraries and Variables

#include <Arduino.h>
#include <ESP8266WiFi.h>
#include <ESPAsyncTCP.h>
#include <ESPAsyncWebServer.h>
#include <LittleFS.h>

// Motor A pins
int motor1Pin1 = 12; 
int motor1Pin2 = 14; 
int enable1Pin = 13; 

// Replace with your network credentials
const char* ssid = "REPLACE_WITH_YOUR_SSID";
const char* password = "REPLACE_WITH_YOUR_PASSWORD";

// Create AsyncWebServer object on port 80
AsyncWebServer server(80);

// Initialize LittleFS
void initFS() {
  if (!LittleFS.begin()) {
    Serial.println("An error has occurred while mounting LittleFS");
  }
  else {
    Serial.println("LittleFS mounted successfully");
  }
}

void initWiFi() {
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  Serial.println("Connecting to WiFi ..");
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print('.');
    delay(1000);
  }
  Serial.println(WiFi.localIP());
}

void moveForward(){
  Serial.println("Moving Forward");
  digitalWrite(enable1Pin, HIGH);
  digitalWrite(motor1Pin1, LOW);
  digitalWrite(motor1Pin2, HIGH);
}

void moveBackward(){
  Serial.println("Moving Backward");
  digitalWrite(enable1Pin, HIGH);
  digitalWrite(motor1Pin1, HIGH);
  digitalWrite(motor1Pin2, LOW);
}

void stopMotor(){
  digitalWrite(enable1Pin, LOW);
  digitalWrite(motor1Pin1, LOW);
  digitalWrite(motor1Pin2, LOW);
}

void setup() {
  Serial.begin(115200);

  // Set motor pins as outputs
  pinMode(motor1Pin1, OUTPUT);
  pinMode(motor1Pin2, OUTPUT);
  pinMode(enable1Pin, OUTPUT);

  initWiFi();
  initFS();

  server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send(LittleFS, "/index.html", "text/html");
  });

  server.serveStatic("/", LittleFS, "/");

  server.on("/forward", HTTP_GET, [](AsyncWebServerRequest *request) {
    moveForward();
    request->send(LittleFS, "/index.html", "text/html", false);
  }); 

  server.on("/backward", HTTP_GET, [](AsyncWebServerRequest *request) {
    moveBackward();
    request->send(LittleFS, "/index.html", "text/html", false);
  });

  server.on("/stop", HTTP_GET, [](AsyncWebServerRequest *request) {
    stopMotor();
    request->send(LittleFS, "/index.html", "text/html", false);
  });

  server.begin();
}

void loop() {
  
}

Define SSID, password, and GPIO pins

Setting Up the Web Server

Create server routes to control forward, reverse, and stop
Use URL query parameters to pass commands

server.on("/motor", HTTP_GET, [](AsyncWebServerRequest *request){
  String command = request->getParam("state")->value();
  if (command == "forward") {
    // rotate forward
  }
});

Motor Control Functions

motorForward()
motorBackward()
motorStop()
Use analogWrite() to control speed via PWM

Uploading Code to ESP8266

Select NodeMCU 1.0 (ESP-12E Module)
Connect via USB and upload code

Designing the Web Interface

HTML Layout

Create buttons for “Forward”, “Reverse”, and “Stop”
Form links send commands via GET requests

<a href="/motor?state=forward">Forward</a>

CSS Styling

Style buttons for usability
Responsive layout for mobile control

JavaScript (Optional)

Use AJAX for real-time control without page reloads

Hosting on ESP8266

Store HTML, CSS, and JS in LittleFS
Upload using ESP8266 LittleFS Uploader

Testing and Troubleshooting

Access web server via IP (e.g., 192.168.1.120)
Test all controls
Check power connections if the motor does not respond
Debug serial output for errors

Enhancements and Advanced Features

Add a speed control slider using HTML input range
Implement password protection for access
Control multiple motors with more GPIOs
Integrate with home automation systems like Home Assistant

FAQs

Can ESP8266 control multiple DC motors simultaneously? Yes, using additional GPIO pins and drivers.

How to control motor speed using ESP8266? Use PWM via analogWrite() on a motor driver enable pin.

What is the maximum current ESP8266 can handle? It is limited; always use external power for motors.

Why is my motor not responding to web commands? Check wiring, power supply, and ensure proper server routing.

How to secure the ESP8266 web server? Implement login authentication and consider using HTTPS with an ESP32.

Conclusion

Controlling a DC motor via a web server using the ESP8266 NodeMCU is not only a practical hands-on project, but a foundational skill for IoT development. With minimal components and an understanding of how web interfaces interact with microcontroller hardware, users can build scalable motor control systems that operate over Wi-Fi. The project can be extended to include multiple motors, sensor feedback, and integration with home automation platforms like Home Assistant. By expanding on this project, you open the door to automation systems that are efficient, reliable, and wirelessly accessible, making it ideal for smart home projects, robotics, and connected machinery.