Pc power remote switch

🖥️ ComputerControl

Remotely power on, restart, and monitor your PC from anywhere in the world — using an ESP32 microcontroller, MQTT, and a sleek web dashboard.

📋 Table of Contents

• Overview
• Architecture
• Features
• Schematic
• Pin Mapping
• Hardware Requirements
• Software Prerequisites
• Getting Started
  • 1. Flash the ESP32 Firmware
  • 2. Configure WiFi & MQTT
  • 3. Deploy the Web Dashboard
• MQTT Topic Reference
• Security Features
• Project Structure
• Legacy System
• Contributing
• License

Overview

ComputerControl is an IoT project that lets you control your PC's power and restart buttons remotely over the internet. An ESP32 physically connects to your PC's front-panel headers via relay modules and monitors the power LED to detect the PC's on/off state.

The system communicates over MQTT (with WebSocket support), enabling a static web dashboard — deployable on Cloudflare Pages or any CDN — to send commands and receive real-time status updates from anywhere.

Architecture

┌──────────────────────────────────────────────────────────────────┐
│                        CLOUD / INTERNET                          │
│                                                                  │
│  ┌─────────────────────┐         ┌────────────────────────────┐  │
│  │   Web Dashboard     │◄──WSS──►│     MQTT Broker            │  │
│  │  (Cloudflare Pages) │         │  (broker.emqx.io or self)  │  │
│  │                     │         │                            │  │
│  │  • Power ON/OFF     │         │  Topics:                   │  │
│  │  • Restart          │         │  computercontrol/{id}/...  │  │
│  │  • Live status      │         │    /status                 │  │
│  │  • Activity log     │         │    /command                │  │
│  └─────────────────────┘         │    /response               │  │
│                                  │    /lwt                    │  │
│                                  └────────────┬───────────────┘  │
│                                               │                  │
└───────────────────────────────────────────────┼──────────────────┘
                                                │ MQTT (TCP 1883)
                                                │
┌───────────────────────────────────────────────┼──────────────────┐
│  LOCAL NETWORK                                │                  │
│                                               │                  │
│                        ┌──────────────────────▼───────────────┐  │
│                        │         ESP32 WROOM-32               │  │
│                        │                                      │  │

Features

Firmware (ESP32)

• Relay control — Momentary press simulation for power and restart buttons
• PC status monitoring — Reads the motherboard power LED to detect ON/OFF state
• WiFiManager — No hardcoded WiFi credentials; configure via captive portal
• MQTT with LWT — Last Will & Testament for instant offline detection
• Rate limiting — Prevents accidental rapid-fire relay triggers (3s cooldown)
• Persistent config — MQTT settings saved to flash via the Preferences library
• Config reset — Hold the BOOT button on power-up to factory reset

Web Dashboard

• Modern glassmorphism UI — Dark theme with ambient background effects
• Real-time status ring — Visual indicator for PC online/offline/unknown states
• MQTT over WebSocket — Connects via wss:// for TLS-encrypted communication
• Activity log — Timestamped log of all events and commands
• Toast notifications — Non-intrusive feedback for actions and errors
• Settings persistence — Browser localStorage with base64 encoding
• Auto-disconnect — Automatically disconnects after 30 minutes of inactivity
• Responsive design — Works on desktop, tablet, and mobile

Schematic

The circuit schematic is designed in KiCad and included in the kicad-circuit/ directory.

Full schematic available as PDF and SVG. The KiCad project files (.kicad_sch, .kicad_pcb, .kicad_pro) are also included for editing.

Key Circuit Details

Wiring to ATX Front Panel Headers

The relay outputs connect in parallel to the motherboard's front-panel power switch (PWR_SW) and reset switch (RST_SW) headers. When the ESP32 activates a relay for 500ms, it mimics a physical button press.

Motherboard PWR_SW Header:       Motherboard RST_SW Header:
  ┌───┐                            ┌───┐
  │ + ├──── Relay 1 COM            │ + ├──── Relay 2 COM
  │ - ├──── Relay 1 NO             │ - ├──── Relay 2 NO
  └───┘                            └───┘

⚠️ Note: GPIO 34 is an input-only pin on the ESP32 — perfect for reading the PC power LED but cannot output signals.

Pin Mapping

Hardware Requirements

Software Prerequisites

Getting Started

1. Flash the ESP32 Firmware

# Clone the repository
git clone https://github.com/Rudra2002/ComputerControl.git
cd ComputerControl

# Build and upload the firmware
cd firmware
pio run --target upload

# Monitor serial output (optional)
pio device monitor --baud 115200

The firmware automatically installs its dependencies (PubSubClient, ArduinoJson, WiFiManager) via PlatformIO.

2. Configure WiFi & MQTT

On first boot (or after a config reset), the ESP32 creates a WiFi access point:

1. Connect to the ComputerControl-Setup WiFi network from your phone or laptop
2. A captive portal opens automatically — enter your WiFi credentials
3. Scroll down to MQTT Configuration and fill in:
   • MQTT Broker Host — e.g. broker.emqx.io (free public broker)
   • MQTT Broker Port — 1883 (TCP) or 8084 (WebSocket TLS on EMQX)
   • Device ID — A unique name like my-pc-ctrl (used to build MQTT topics)
   • MQTT Username / Password — optional, depends on your broker
4. Click Save — the ESP32 connects to WiFi and the MQTT broker

To reset configuration: Hold the BOOT button (GPIO 0) while powering on the ESP32. The LED will blink rapidly, and the captive portal will reappear.

3. Deploy the Web Dashboard

Local Development

cd web
npm install
npm run dev
# Opens at http://localhost:3000

Production Build (for Cloudflare Pages, Netlify, etc.)

cd web
npm run build
# Output in web/dist/ — deploy this folder

Connecting the Dashboard

1. Open the web dashboard in your browser
2. Enter your MQTT broker's WebSocket URL — e.g. wss://broker.emqx.io:8084/mqtt
3. Enter the Device ID you configured on the ESP32
4. (Optional) Enter MQTT username/password if your broker requires authentication
5. Click Connect — the dashboard will show real-time PC status

MQTT Topic Reference

All topics follow the pattern: computercontrol/{device_id}/...

Security Features

Project Structure

ComputerControl/
├── firmware/                  # ESP32 firmware (PlatformIO)
│   ├── platformio.ini         # Build config & dependencies
│   └── src/
│       ├── config.h           # Pin definitions, timing, MQTT defaults
│       └── main.cpp           # Main firmware — WiFi, MQTT, relay logic
│
├── web/                       # Web dashboard (Vite + vanilla JS)
│   ├── index.html             # Dashboard HTML (connect screen + dashboard)
│   ├── package.json           # npm dependencies (mqtt.js)
│   ├── vite.config.js         # Vite dev server config
│   └── src/
│       ├── main.js            # MQTT client, UI logic, command handling
│       └── style.css          # Glassmorphism dark theme, animations
│
├── kicad-circuit/             # Hardware schematic (KiCad 8)
│   ├── pc-power-remote-switch.kicad_sch   # Schematic source
│   ├── pc-power-remote-switch.kicad_pcb   # PCB layout
│   ├── pc-power-remote-switch.kicad_pro   # KiCad project file
│   ├── scematic.png           # Schematic render (PNG)
│   ├── scematic.pdf           # Schematic render (PDF)
│   └── pc-power-remote-switch.svg         # Schematic render (SVG)
│
├── LeagacySystem/             # Legacy ESP8266 firmware (archived)

Legacy System

The LeagacySystem/ directory contains the original ESP8266-based implementation that served a web dashboard directly from the microcontroller via LittleFS. This has been superseded by the current ESP32 + MQTT architecture, which offers:

• ✅ Remote access — Control from anywhere, not just on local network
• ✅ Separation of concerns — Web frontend hosted independently on a CDN
• ✅ Better security — MQTT authentication, TLS, rate limiting
• ✅ Reliability — LWT for offline detection, auto-reconnect

The legacy code is kept for reference purposes.

Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/my-feature)
3. Commit your changes (git commit -m 'Add my feature')
4. Push to the branch (git push origin feature/my-feature)
5. Open a Pull Request

License

This project is open source and available under the MIT License.

Built with ❤️ using ESP32 + MQTT + Vite
_{Designed & developed by Rudra}