BS ISO 20794-4:2020 - Road Vehicles Clock Extension Peripheral Interface (CXPI)

The BS ISO 20794-4:2020 is a pivotal standard for the automotive industry, focusing on the Clock Extension Peripheral Interface (CXPI) for road vehicles. This comprehensive document, released on February 13, 2020, provides detailed specifications for both the data link layer and the physical layer of the CXPI, ensuring seamless communication and integration within modern vehicular systems.

Key Features and Benefits

• Standard Number: BS ISO 20794-4:2020
• Pages: 70
• ISBN: 978 0 580 97226 3
• Status: Standard

The CXPI standard is designed to enhance the efficiency and reliability of communication systems in road vehicles. By defining the data link and physical layers, this standard ensures that automotive manufacturers and engineers can develop systems that are both interoperable and future-proof.

Understanding CXPI

The Clock Extension Peripheral Interface (CXPI) is a communication protocol that is increasingly being adopted in the automotive industry. It serves as a cost-effective alternative to the more complex and expensive Controller Area Network (CAN) systems, providing a simpler yet robust solution for in-vehicle communication.

CXPI is particularly advantageous in applications where the communication speed and data volume requirements are moderate, making it ideal for use in body electronics, such as lighting, climate control, and seat adjustment systems. The BS ISO 20794-4:2020 standard outlines the necessary protocols and physical layer requirements to ensure that CXPI systems operate efficiently and reliably.

Data Link Layer

The data link layer is a critical component of the CXPI standard, responsible for the reliable transmission of data across the network. This layer manages error detection and correction, ensuring that data integrity is maintained throughout the communication process. The BS ISO 20794-4:2020 standard provides detailed guidelines on how to implement these protocols effectively, allowing for seamless data exchange between different components within a vehicle.

Physical Layer

The physical layer of the CXPI standard defines the electrical and physical specifications for the network. This includes the wiring, connectors, and signal characteristics that are necessary for establishing a reliable communication link. By adhering to the specifications outlined in the BS ISO 20794-4:2020 standard, manufacturers can ensure that their systems are compatible with other CXPI-compliant devices, facilitating easier integration and reducing the risk of communication failures.

Why Choose BS ISO 20794-4:2020?

Adopting the BS ISO 20794-4:2020 standard offers numerous benefits for automotive manufacturers and engineers. By following this standard, you can:

• Ensure compatibility and interoperability between different vehicle systems.
• Reduce development costs by utilizing a standardized communication protocol.
• Enhance the reliability and efficiency of in-vehicle communication systems.
• Stay ahead of industry trends by adopting a modern and widely accepted standard.

Conclusion

The BS ISO 20794-4:2020 standard is an essential resource for anyone involved in the design and development of automotive communication systems. With its comprehensive guidelines and specifications, this standard provides the foundation for creating reliable, efficient, and interoperable CXPI systems. Whether you are an automotive manufacturer, engineer, or researcher, the BS ISO 20794-4:2020 standard is a valuable tool that can help you achieve your goals and stay competitive in the ever-evolving automotive industry.

BS ISO 20794-4:2020

This standard BS ISO 20794-4:2020 Road vehicles. Clock extension peripheral interface (CXPI) is classified in these ICS categories:

• 43.040.15 Car informatics. On board computer systems

This document specifies the CXPI data link layer and the CXPI physical layer.

The DLL is based on:

• priority-based CXPI network access;

• non-destructive content-based arbitration;

• broadcast frame transfer and acceptance filtering; and

• node related error detection and error signalling.

The CXPI physical layer (PHY) requirements comprise of:

• physical signalling (PS) sub-layer, which specifies the requirements of the clock generation function, the encoding and decoding of CXPI frames, and bit-wise collision resolution logic;

• physical media attachment (PMA) sub-layer, which specifies the requirements of the signal shaping waveform logic;

• physical media dependent (PMD) sub-layer, which specifies the requirements of the CXPI network termination, electrostatic discharge protection, etc., and device connector requirements; and

• physical media (PM), which specifies the requirements of the CXPI network cable/wiring harness.