Electrical Test Bench Project

This project involves developing a comprehensive user interface for an electrical test board that interfaces with CAN (Controller Area Network) communication. The system serves as a tester board for electrical members to mock and read signals over CAN networks, displaying real-time telemetry data received from CAN networks and providing the ability to mock CAN inputs.

Link to docs https://www.waveshare.com/wiki/RS485_CAN_HAT#Install_Library

CAN Messages: https://docs.google.com/spreadsheets/d/12O2UPdM_fqUVKd0IXZ638wb1obtBXQp11giv7swfWM4/edit?gid=575020774#gid=575020774

Project Structure

can-snooper/
├── api/                           # WebSocket server for real-time CAN data
│   ├── __init__.py
│   └── main.py                    # WebSocket server with real CAN bus
├── can_utils/                     # Utility modules for CAN operations
│   ├── __init__.py
│   ├── data_classes.py           # Data structures for CAN messages
│   ├── read_can_messages.py      # Enhanced CAN message reader with parsing
│   └── send_messages.py          # CAN message transmission utilities
├── frontend/                      # React web dashboard
│   ├── src/
│   ├── package.json
│   └── ...                       # React/Vite frontend files
├── sc1-data-format/              # Git submodule for CAN signal definitions
├── mock_messages.py              # WebSocket server with simulated CAN data
├── read_can_messages.py          # Simple CAN message listener
├── send_messages.py              # Simple CAN message sender
├── requirements.txt              # Python dependencies
└── README.md

Setup Instructions

1. Initialize Submodules

This project uses git submodules. After cloning, initialize them with:

git submodule update --init --recursive

2. Create Virtual Environment

Create virtual environment using:

• Windows: virtualenv -p python3 .env
• Linux/MacOS: python3 -m venv .env

3. Activate Virtual Environment

Activate the virtual environment you created:

• Windows: .env\Scripts\activate
• Linux/MacOS: source .env/bin/activate

4. Install Dependencies

Install the required Python libraries:

pip install -r requirements.txt

Usage Instructions

For CAN Message Listening

Simple Console Listener (Utility Module)

Listen to CAN messages and print decoded values to console:

python read_can_messages.py

• Connects to can0 by default
• Displays decoded signal names and values
• Press Ctrl+C to stop

WebSocket Server (Real CAN Bus)

Start WebSocket server that broadcasts real CAN data to connected clients:

python api/main.py

• Listens on CAN bus can0
• WebSocket server runs on ws://localhost:8765
• Broadcasts parsed CAN messages as JSON to all connected clients via Websocket server

Mock Data Server (Development/Testing Frontend)

Start WebSocket server with simulated CAN data for testing:

python mock_messages.py

• Generates fake CAN messages every 2 seconds
• WebSocket server runs on ws://localhost:8765
• Useful for frontend development without real CAN hardware

For CAN Message Sending (Utility Module)

Send custom CAN messages interactively:

python send_messages.py <channel>

Example:

python send_messages.py can0

The script will prompt you for:

• Message ID: Enter hex ID (e.g., 0x123)
• Data bytes: Enter hex bytes separated by spaces (e.g., 11 22 33 44)

For Web Dashboard

Setup Frontend

Navigate to the frontend directory and install dependencies:

cd frontend
npm install

Run Development Server

Start the React development server:

npm run dev

• Frontend runs on http://localhost:5173
• Connects to WebSocket server for real-time CAN data

Common Use Cases

1. Development & Testing: Use mock_messages.py + frontend for UI development
2. Real Vehicle Testing: Use api/main.py + frontend for live CAN monitoring
3. Debugging CAN Issues: Use read_can_messages.py for quick console output
4. Sending Test Messages: Use send_messages.py to inject test CAN messages

Requirements

• Hardware: CAN interface (e.g., Waveshare RS485 CAN HAT)
• OS: Linux with SocketCAN support (for real CAN bus)
• Python: 3.7+ with python-can and websockets libraries
• Node.js: For frontend development