Overview - ISO 17987-3:2016 (LIN Protocol specification)
ISO 17987-3:2016 defines the logical protocol for the Local Interconnect Network (LIN), a low-cost, low-speed in-vehicle communications bus used for body and comfort electronics. The standard specifies signal management, frame transfer, schedule table handling, task behaviour, status management, and the behaviour of LIN master and slave nodes. It also includes OSI layer‑5 properties for UDS-on-LIN node configuration and identification services as defined in ISO 14229‑7.
Keywords: ISO 17987-3:2016, LIN protocol, Local Interconnect Network, automotive LIN, UDSonLIN, ISO 14229-7.
Key topics and technical requirements
- Protocol model and node concept - master-driven header and slave responses; frame header contains break, sync and a protected identifier (PID) (6‑bit frame ID + 2 parity bits).
- Frame types - unconditional, sporadic, event‑triggered and diagnostic frames; each frame has a header and response (1–8 data bytes).
- Signal management - mapping of signals to frame data bytes; publishers and subscribers.
- Schedule tables - deterministic, table-driven timing for frame slots and cluster behaviour.
- Task behaviour and status management - state models for operational, bus‑sleep and wake‑up handling; error detection and signalling.
- Checksum models - classic checksum (for diagnostic/legacy frames) and enhanced checksum (for non‑diagnostic frames).
- Transport and diagnostics - support for transport layer services to transfer larger PDUs (UDS diagnostic services B016–B816 on LIN).
- Node configuration & identification - LIN product identification, Node Capability File (NCF) concepts, and how slave nodes are modelled.
- Bitrate and physical context - LIN is a UART‑based link supporting typical bit rates from 1 kbit/s to 20 kbit/s (physical layer covered in Part 4).
- Conformance & testability - references to Part 6 (protocol conformance tests) and Part 7 (EPL conformance).
Practical applications and users
- Targeted for low‑cost automotive control domains such as door modules, HVAC, seat control, mirror control and other body electronics.
- Useful for:
- Automotive systems architects designing in‑vehicle networks
- Embedded firmware developers implementing LIN master/slave stacks
- Tool vendors creating LIN description files (LDF), Node Capability Files (NCF) and APIs
- Test engineers performing conformance and diagnostic validation
- Tier‑1 suppliers integrating LIN nodes into vehicle clusters
Related standards
- ISO 17987-1: General information and use cases
- ISO 17987-2: Transport protocol and network layer services
- ISO 17987-4 & 7: Electrical Physical Layer (EPL) and EPL conformance tests
- ISO 17987-5: LIN API (node configuration/identification services)
- ISO 17987-6: Protocol conformance test specification
- ISO 14229-7: UDSonLIN (UDS diagnostics over LIN)
This standard is essential when implementing deterministic, master/slave LIN clusters and for ensuring interoperability, diagnostic capability and conformity with LIN network best practices.
