CANpeek

CANpeek is a graphical CAN bus observer and analyzer for Linux and Windows based on Python and Qt with can databases (DBC) support and some CANopen functionality.

Features

• 🧩 Project-based configuration with filters, DBC files, and persistent decoding options
• 🌐 Multi-interface support: socketcan, pcan, kvaser, vector and other interfaces based on python-can
• 📊 Dual View: Real-time Trace View and hierarchical Grouped View with signal expansion
• 📁 Multi-DBC support with signal decoding from cantools
• 🧠 Generic CANopen decoder with support for NMT, PDO, SDO, Heartbeat, and more
• 🗃️ CANopen Object Dictionary with an SDO client for read/write operations
• 📦 CAN frame transmitter, supporting both raw and signal-based (DBC) messages
• 📜 Log support: Save/load CAN logs in all python-can IO formats
• 🔌 Connections Management: Handling of multiple simultaneous CAN connections

Screenshots

Installation

The interfaces avaibility depends on modules and drivers available on your system. Watch console output at startup.

With pip

Use the extra [interfaces] to install optionals python modules.

pip install canpeek[interfaces]
canpeek

From source

1. Install uv
2. Run uv run canpeek --extra interfaces

🤖 About the Code (aka “AI Slop” Warning)

This project includes code — and this very README — that were generated almost entirely with large language models (LLMs). Yes, the term “AI slop” was insisted upon.

While the app works and provides a full-featured CAN bus GUI, you may find:

• Some awkward structure and bloated chunks of logic
• Repetitive patterns that could use refactoring
• Giant all-in-one files (yes, main.py, we’re looking at you)
• Documentation (including this README) was AI-generated too — so if it sounds polished but slightly overconfident, that’s why.

The goal was rapid prototyping, not pristine architecture. Use it, improve it, rewrite parts of it — all contributions are welcome.

Usage

1. Connect to a CAN interface:

   • Select backend (socketcan, pcan, kvaser, etc.)
   • Enter the channel (e.g., can0)
   • Click Connect

2. Load DBC files via the "Project Explorer" to decode signals.

3. Create Filters to limit visible traffic.

4. Send CAN messages:

   • Manually from the Transmit tab
   • If the message id is in the DBC, a dedicated panel is available to edit signals values

5. Save / Load CAN logs in multiples formats.

Other tools

CANPeek is designed to be quick & simple, you might find those intersesting:

• cangaroo : A rather similar project in c++
• SavvyCAN : A much more complete canbus tool

License

• This project is licensed by MIT License
• icons : Yaru : CC BY-SA 4.0