🏢 8051 Elevator Control System Simulator

A high-fidelity, real-time elevator control system originally designed to interface with 8051 Assembly firmware via physical UART. It has been evolved into a robust, 16-floor full-stack simulation deployed on the web.

This project bridges low-level embedded systems concepts (Finite State Machines, ISRs, UART communication) with modern web technologies to create a seamlessly integrated, industrial-grade elevator cabin UI.

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🚀 Live Demo & Testing

You can interact with the live simulation online here:
🔗 Elevator Control System (Hosted on Render)

How to Test Online:

1. Call the Elevator: Click any lighted floor button (G through 15) on the right-side control panel. The button rim will glow orange to indicate the call is queued.
2. Observe the State: Watch the top digital indicator dynamically update the floor and travel direction (▲/▼).
3. Analytics: The right-hand "System Analytics" panel shows the real-time continuous vertical position of the cabin and the underlying backend serial metrics stream.
4. Emergency: Press the red STOP (Emergency) button at any time. The elevator software will force a halt, clear all queues, and immediately open the doors safely.

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✨ Key Features

• 16-Floor Navigation: Full travel capabilities between Ground and the 15th floor with a dynamic, camera-following background viewport simulating vertical movement.
• Smart LOOK Scheduling Algorithm: Implements a realistic disk-scheduling style algorithm handling simultaneous multi-floor requests, direction pivoting, and continuous non-redundant sweeps.
• Real-time WebSockets: Bidirectional, low-latency communication using Flask-SocketIO to sync backend FSM ticks with frontend cabin UI rendering.
• Dual Execution Modes:
  • Hardware Mode: Attempts to bridge directly with Keil μVision via simulated COM ports sending HEX buffers.
  • Virtual Core Mode (Cloud): Falls back to a deterministic Python-based 8051 FSM emulator when deployed to cloud servers like Render.

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🧠 Technical Architecture

1. The Presentation Layer (Frontend)

Built using standard HTML / CSS / Vanilla JavaScript. It strictly acts as a "dumb terminal" — it makes zero logic decisions. It purely displays the state handed to it by the backend WebSockets (io()) and sends back button-press events.

• Advanced CSS methodologies are utilized to give it a photorealistic, brushed-metal feeling with micro-interactions and incandescent LED glows.

2. The Bridge Layer (Backend)

Built with Python, Flask, and Gunicorn.

• Utilizes asynchronous Eventlet workers to manage infinite hardware loops without blocking standard web traffic.
• Manages the global serial_reader_thread tracking continuous hardware state.

3. The Logic Core (8051 Emulator)

If hardware serial is absent (like on Render), the backend implements a strict Core8051Simulator class.

• Emulates states: IDLE, MOVING, SETTLING, DOOR_OPEN, DOOR_CLOSING.
• Emulates exact Interrupts and TARGET_MASK bitwise operations as originally implemented in the .asm codebase.

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⚙️ The LOOK Elevator Algorithm

Instead of blindly serving requests (First-Come First-Serve), the backend determines the optimal travel path using the LOOK Algorithm:

1. When moving UP, the elevator will continue satisfying all requested floors above it.
2. It stops strictly at the highest requested floor, reversing direction DOWN if and only if there are queued requests below it.
3. This prevents "starvation" of users at extreme ends of the building while minimizing travel distance.

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🛠️ Local Development

Prerequisites

• Python 3.10+
• If you intend to use the actual 8051 code: Keil μVision and a Virtual Serial Port.

Setup

1. Clone this repository to your local machine.
2. Create and activate a virtual environment:

   python -m venv .venv
   source .venv/bin/activate  # On Windows use: .venv\Scripts\activate

3. Install the required dependencies:

   pip install -r requirements.txt

4. Start the development server:

   python server.py

5. Navigate to http://localhost:5000 in your web browser.

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☁️ Deployment (Render)

This repository is configured out-of-the-box for Render.com Platform-as-a-Service using the included render.yaml Blueprint and Procfile.

• Runtime: Python 3.11.8
• Web Server: Gunicorn with eventlet async workers.
• Environment: To deploy, simply link your GitHub to Render and it will auto-detect the provided build parameters.