1. Introduction
The M5Stack Official CANBus Unit (CA-IS3050G) is a standalone Controller Area Network (CAN) transceiver unit designed for building complex CAN communication networks. It features a built-in DC-DC isolation power chip to effectively isolate noise and interference, thereby protecting sensitive circuits from damage. This unit is ideal for applications requiring robust and reliable CAN communication.
The CA-IS3050G model provides differential reception and transmission capabilities, supporting up to 110 nodes with a signal transmission rate of up to 1 Mbps. It incorporates essential protection functions such as current limiting, overvoltage protection, ground loss protection (–40V to 40V), and thermal shutdown, ensuring output short-circuit prevention. The unit complies with the ISO11898-2 standard technical specifications.
CAN is an ISO international standard serial communication protocol, belonging to the fieldbus category. It supports distributed control and real-time control through a multi-master competitive arbitration method, characterized by multi-master operation, decentralized arbitration, and broadcast communication. Its advantages include high-speed data communication, low failure rate, and congestion avoidance when multiple nodes communicate simultaneously. The communication distance can reach 10 km (at rates less than 5 Kbps) or 40 m (at 1 Mbps).
2. Key Features
- Built-in isolated DC-DC power supply for noise and interference isolation.
- Power indicator light for operational status.
- Supports signal rates up to 1 Mbps.
- Comprehensive protection functions: signal isolation, current limiting, over-voltage protection, ground loss protection (–40V to 40V), and thermal shutdown.
- Equipped with 2 LEGO-compatible holes for easy integration.
- Features a HY2.0-4P interface for connectivity.
3. Package Contents
The following items are included in your M5Stack Official CANBus Unit package:
- 1 x Unit CAN (CA-IS3050G)
- 1 x HY2.0-4P Grove connection cable (20cm)
- 1 x VH3.96-4P connector
- 1 x 120R resistor
4. Technical Specifications
| Resource | Parameter |
|---|---|
| Rated withstand voltage | 1000V |
| Maximum rate | 1 Mbps |
| Number of theoretical nodes | 110 |
| Low loop delay | -150ns |
| Common mode voltage | -12V ~ 12V |
| Protection functions | Current limiting, overvoltage, dominant timeout, thermal shutdown |
| Case Material | PC |
| Product Size | 56.0 x 24.0 x 10.2mm |
| Net Weight | 9.1g |
| Package Size | 138.0 x 93.0 x 11.2mm |
| Gross Weight | 17.1g |
5. Pinout Diagram
The CANBus Unit features a clear pinout for easy connection. The HY2.0-4P interface connects to the M5Core, providing power and communication lines.
| M5Core (Port C) | GPIO16 | GPIO17 | 5V | GND |
|---|---|---|---|---|
| CAN Unit | RXD | TXD | 5V | GND |
The VH3.96-4P connector provides the CAN bus interface:
| Pin | Description |
|---|---|
| H | CAN_H |
| L | CAN_L |
| G | GND |
6. Schematic Diagram
For detailed circuit information, refer to the schematic diagram below. This diagram illustrates the internal components and connections of the CANBus Unit, including the isolated CAN transceiver (CA-IS3050G), isolated 5V power supply, and Grove LDO.
7. Product Dimensions
The physical dimensions of the CANBus Unit are provided in the diagram below (all measurements in mm).
8. Setup and Connection
To set up your M5Stack CANBus Unit, follow these steps:
- Connect to M5Core: Use the provided HY2.0-4P Grove connection cable to connect the CANBus Unit to Port C (GPIO16/GPIO17) on your M5Core device.
- CAN Bus Connection: Connect your CAN bus network to the VH3.96-4P connector on the CANBus Unit. Ensure correct polarity for CAN_H, CAN_L, and GND.
- Termination Resistor: If the CANBus Unit is at either end of the CAN bus, connect the 120R resistor across CAN_H and CAN_L for proper bus termination.
- Power On: Once connections are secure, power on your M5Core device. The power indicator light on the CANBus Unit should illuminate, indicating it is receiving power.
9. Operating Instructions
The CANBus Unit facilitates communication over a CAN bus. After proper setup, you can use your M5Core to send and receive CAN messages.
- Software Configuration: Load appropriate CAN communication firmware onto your M5Core. This typically involves setting up the CAN controller, baud rate, and message filters.
- Sending Messages: Use your M5Core's programming environment (e.g., Arduino IDE with M5Stack libraries, UiFlow) to construct and send CAN messages. The CANBus Unit will transmit these messages onto the CAN bus.
- Receiving Messages: Configure your M5Core to listen for incoming CAN messages. The CANBus Unit will receive messages from the bus and forward them to the M5Core for processing.
- Monitoring: Observe the power indicator light on the CANBus Unit. While it primarily indicates power, successful communication can often be inferred from the application running on the M5Core.
10. Typical Applications
The M5Stack CANBus Unit is suitable for a variety of applications requiring reliable CAN communication:
- CAN bus communication systems
- Industrial field control and automation
- Security systems and access control
- Internet of Things (IoT) projects requiring robust data exchange
- Automotive diagnostics and control (non-critical systems)
11. Software and Documentation Resources
To get started with programming and further understanding your CANBus Unit, refer to the following resources:
- User Manual (PDF): For a comprehensive guide, you can download the official user manual: M5Stack CANBus Unit User Manual (PDF)
- Datasheet: CA-IS3050G Transceiver Datasheet
- Arduino: CAN-Transceiver TEST example code.
- UiFlow1: Unit CAN UiFlow1 Documentation.
- UiFlow2: Unit CAN UiFlow2 Documentation.
- EasyLoader: Unit CAN example with M5Core (download available).
12. User Tips
- Always ensure proper termination resistors (120 Ohm) are used at both ends of the CAN bus to prevent signal reflections, especially in longer bus lines.
- Verify the baud rate settings in your software match the baud rate of the CAN bus network for successful communication.
- When troubleshooting, check all physical connections and ensure the M5Core is correctly programmed for CAN communication.
13. Troubleshooting
If you encounter issues with your CANBus Unit, consider the following:
- No Communication:
- Check all wiring connections, especially the HY2.0-4P cable to the M5Core and the VH3.96-4P to the CAN bus.
- Verify that the CAN bus is properly terminated with 120 Ohm resistors at its ends.
- Ensure the baud rate configured in your M5Core software matches the baud rate of the CAN network.
- Confirm that the M5Core is powered on and the CANBus Unit's power indicator light is active.
- Intermittent Communication:
- This can often be caused by improper termination or excessive bus length. Review your bus topology and termination.
- Check for external noise sources that might be interfering with the CAN signals.
- Unit Not Powering On:
- Ensure the M5Core is providing 5V power to the Grove port.
- Inspect the HY2.0-4P cable for damage.
14. Care and Maintenance
To ensure the longevity and optimal performance of your M5Stack CANBus Unit:
- Keep the unit clean and free from dust and debris. Use a soft, dry cloth for cleaning.
- Avoid exposing the unit to extreme temperatures, humidity, or direct sunlight.
- Handle the unit with care to prevent physical damage to the connectors or internal components.
- Store the unit in a dry, cool environment when not in use.
15. Warranty and Support
For warranty information, technical support, and further assistance, please contact the M5Stack Official Store or refer to the official M5Stack website. Keep your purchase receipt for warranty claims.
