Bridging Multiple Electronic Control Modules and Buses in Automotive Systems

October 10, 2024 02:27 PM - By Rachael

ATI’s VCG-1 Gateway Solution

When designing modern automotive systems, the challenge of bridging multiple electronic control modules that operate over different communication buses is critical. These systems use a variety of communication protocols, such as CAN, CAN-FD, LIN, and Ethernet, each with its own physical layer, speed, and data-handling capabilities. In this context, Accurate Technologies Inc. (ATI) provides a technical solution with the VCG-1 Vehicle Communication Gateway, which acts as a powerful protocol bridge for synchronizing data traffic across these disparate networks.

Overview of the VCG-1 Gateway

The VCG-1 is engineered to support 6 CAN-FD channels, 2 LIN channels, and 1 100Base-T1 Automotive Ethernet channel. This configuration allows the gateway to interface with different subsystems within a vehicle, which may communicate using older CAN 2.0B, faster CAN-FD, or the newer Automotive Ethernet. The VCG-1’s strength lies in its ability to act as a bridge between these interfaces, performing message translation and routing while maintaining message integrity and ensuring optimal performance between systems that use different communication speeds and protocols.

For instance, CAN-FD supports higher bit rates (up to 8 Mbps), allowing for larger data payloads compared to the traditional CAN 2.0B, which is limited to 1 Mbps. The VCG-1 enables seamless message transfer between these two CAN variants by handling differences in bit timing and message structure. Similarly, it converts CAN messages for transmission over LIN, a protocol typically used for lower-speed communications, such as in vehicle body electronics (e.g., window controllers, seat heaters). This capability is crucial when integrating legacy systems with more modern architectures.

Hardware and Protocol Bridging

The hardware design of the VCG-1 is robust, featuring galvanic isolation on all CAN channels. This prevents ground loops and electrical interference, which can be particularly problematic in automotive environments, ensuring the integrity of communication between different modules. The VCG-1 also has physical termination switches for each CAN channel, allowing for correct bus termination, a critical requirement in high-speed communication systems where reflection and impedance mismatches can corrupt data.

Additionally, the Automotive Ethernet channel offers high-speed data transfer, which is increasingly important for modern vehicles that integrate systems like advanced driver assistance systems (ADAS) or multimedia services. Ethernet in this context provides more bandwidth than CAN or LIN, making it suitable for high-data-rate applications.

Configuration and Flexibility

The VCG-1 uses a flexible, scriptable interface for data routing and translation, relying on ECMAScript for custom processing of messages between networks. This scriptable flexibility enables engineers to design precise data-handling rules, ensuring that only relevant messages are forwarded or modified as needed. For example, engineers can configure the VCG-1 to selectively forward diagnostic data from a CAN-FD network to an external diagnostic tool connected via Ethernet.

The device is also designed for ease of configuration. It supports PC-based configuration via a USB connection and a built-in web interface. The VCG-1’s user-friendly FAT32 file system on an internal SD card allows configurations to be transferred easily between devices, and real-time scripting can be performed through a web browser without requiring additional PC software

Integration into Broader ATI Ecosystem

ATI provides an ecosystem of tools to complement the VCG-1, such as CANLab, a software suite designed for network analysis of CAN and LIN systems. CANLab can decode messages, view bus traffic, log data, and perform post-analysis, ensuring that communication networks are functioning properly throughout the development and validation phases. Coupled with the CANary interfaces, which simplify CAN network interfacing, the VCG-1 integrates smoothly into this broader ecosystem, making it a versatile tool for engineers working on multi-protocol vehicle systems

Conclusion

ATI’s VCG-1 provides a versatile and robust solution for bridging multiple communication protocols in vehicles, ensuring data can flow seamlessly between different systems that use CAN, CAN-FD, LIN, or Ethernet. Its configurable, script-driven approach allows for precise message handling, and its rugged hardware ensures it can operate reliably in harsh automotive environments. This makes it a crucial tool in modern automotive development, where integrating and managing communication across diverse systems is essential.

Learn More