ISO 17458-2-2013 PDF

Full title and description

ISO 17458-2:2013 — Road vehicles — FlexRay communications system — Part 2: Data link layer specification. This part of ISO 17458 specifies the data link layer (protocol behavior, frame formats, timing and control, coding/decoding, error detection and signalling) for the FlexRay deterministic communications system used in automotive applications.

Abstract

ISO 17458-2:2013 defines the FlexRay data link layer protocol for dependable automotive networks. It covers synchronous and asynchronous frame transfer, guaranteed latency and jitter for time-triggered (synchronous) communication, prioritization for event-driven (asynchronous) traffic, single- and multi-master clock synchronization, inter-network time synchronisation, error detection and signalling, and scalable fault tolerance mechanisms required for safety-critical in-vehicle communication.

General information

• Status: Published (confirmed)
• Publication date: February 2013 (Edition 1, 2013)
• Publisher: International Organization for Standardization (ISO)
• ICS / categories: 43.040.15 (Car informatics / on-board computer systems)
• Edition / version: Edition 1 (2013)
• Number of pages: 352

Scope

This standard specifies the behaviour and structure of the FlexRay data link layer used in road vehicles. It defines message/frame formatting (header and payload), timing and scheduling for time-triggered and event-triggered transfers, synchronization methods, node roles, protocol operation control, coding and decoding procedures, bit-strobing and wake-up processes, fault containment and error signalling, and network topology considerations relevant to FlexRay clusters.

Key topics and requirements

• Data link layer protocol operation: state machines, control processes and scheduling for deterministic communication.
• Frame structure and formats: header, payload, cycle, slot and minislots definitions; payload length limits and structure.
• Synchronous (time-triggered) and asynchronous (event-driven) transfer modes, including guaranteed latency and jitter constraints for synchronous frames.
• Clock and time synchronization: single- and multi-master schemes and inter-network time synchronisation principles.
• Coding, decoding and bit-strobing mechanisms used to ensure reliable bit-level transfer and delimitation.
• Error detection, signalling and fault-tolerance features to support dependable in-vehicle communications.
• Network topology considerations and node roles (e.g., cluster management, communication controllers).
• Wake-up patterns and low-power wake-up behaviour for bus operation.

Typical use and users

ISO 17458-2 is used by automotive OEMs, electronic control unit (ECU) and communications-controller vendors, in-vehicle network architects, embedded software and firmware developers, test laboratories, and tooling providers (conformance/test equipment). It is applied when designing, implementing and verifying FlexRay-based communication systems for safety-critical and real-time automotive applications (e.g., advanced driver assistance, coordinated control domains).

Related standards

ISO 17458 is a multi-part series. Closely related parts include ISO 17458-1 (general information and use cases), ISO 17458-3 (data link layer conformance test specification), ISO 17458-4 (electrical physical layer specification) and ISO 17458-5 (electrical physical layer conformance test specification). Implementers also commonly reference AUTOSAR and other automotive communications and safety standards when integrating FlexRay into vehicle platforms.

Keywords

FlexRay, data link layer, road vehicles, automotive network, time-triggered communication, synchronous transfer, asynchronous transfer, deterministic communications, frame format, synchronization, fault tolerance, conformance testing, ECU, in-vehicle network.

FAQ

Q: What is this standard?

A: ISO 17458-2:2013 is the international standard that defines the data link layer specification for the FlexRay communications system used in road vehicles.

Q: What does it cover?

A: It covers the behaviour and protocol mechanisms at the data link layer: frame formats, synchronous and asynchronous transfer rules, timing and scheduling, synchronization mechanisms, coding/decoding procedures, error detection and signalling, and topology and node-role considerations.

Q: Who typically uses it?

A: Automotive OEMs, ECU and communications-controller manufacturers, embedded software engineers, test laboratories and tool vendors use it to design, implement and verify FlexRay-based in-vehicle communication systems.

Q: Is it current or superseded?

A: ISO 17458-2:2013 was published in 2013 (Edition 1) and has been maintained in ISO's review cycle; it is published and confirmed as current.

Q: Is it part of a series?

A: Yes. ISO 17458 is a multipart series; other parts include ISO 17458-1, -3, -4 and -5 which respectively cover general information, conformance tests for the data link layer, the electrical physical layer, and conformance tests for the physical layer.

Q: What are the key keywords?

A: FlexRay, data link layer, deterministic, time-triggered, synchronous transfer, asynchronous transfer, frame format, synchronization, fault tolerance, automotive network.