LIN Network for Vehicle ApplicationsIssued 2004-08Revised 2005-09Superseding J2602-1 AUG2004
6. Section 5.7.2.5 – The Broadcast message IDs mapping has been clarified.
7. Section 5.7.3 – Added additional requirements for device behavior when a Targeted Reset command
is received to make the behavior more predictable.
8. Section 5.8.2 – Added a note about signal consistency in the J2602 Status Byte.
9. New Section 5.8.4 – Inserted between 5.8.3 and old 5.8.4. Define repeat usage of signals in frames. 10. Section 5.8.6.1.3 – Tx Bit Error has been changed to Data Error to include the case where a slave
receives a data byte other than $55 for the sync byte.
11. Section 5.8.6.2.1 – This section has been added to define a use for APINFO4. This bit has now been
defined to indicate that the Slave application is requesting service from the Master. 12. Section 6.3 – Refers to J2602-3 for API requirements.
13. Section 7.2.1 – The wake-up pulses sent by the slave had minimum times between repeats, but no
maximum times. This has been addressed.
14. Section 7.12.2 – Additional information has been added as to the behavior of the system during an
over-voltage event. 1.2
Mission/Theme
This serial data link network is intended for use in applications where high data rate is not required and a lower data rate can achieve cost reductions in both the physical media components and in the microprocessor and/or dedicated logic devices (ASICs) which use the network. 1.3
Overview
LIN is a single wire, low cost, Class A communication protocol. LIN is a master-slave protocol, and utilizes the basic functionality of most Universal Asynchronous Receiver Transmitter (UART) or Serial Communication Interface (SCI) devices as the protocol controllers in both Master and Slave devices. To meet the target of “Lower cost than either an OEM proprietary communications link or CAN link” for low speed data transfer requirements, a single wire transmission media based on the ISO 9141 specification was chosen. The protocol is implemented around a UART/SCI capability set, because the silicon footprint is small (lower cost). Many small microprocessors are equipped with either a UART or SCI interface (lower cost), and the software interface to these devices is relatively simple to implement (lower software cost). Finally, the relatively simplistic nature of the protocol controller (UART/SCI) and the nature of state-based operation, enable the creation of Application Specific Integrated Circuits (ASICs) to perform as input sensor gathering and actuator output controlling devices, in the vein of Mechatronics.
All message traffic on the bus is initiated by the Master device. Slave devices receive commands and respond to requests from the Master. Since the Master initiates all bus traffic, it follows that the Slaves cannot communicate unless requested by the Master. However, Slave devices can generate a bus wakeup, if their inherent functionality requires this feature.
The “LIN Consortium” developed the set of LIN specifications. The Consortium is a group of automotive OEMs, semiconductor manufacturers, and communication software and tool developers. The LIN specification set is “released” by the LIN Steering Committee, a closed subset of the members. Associate Consortium members contribute to the formation of the specifications through participation in LIN Work Groups; however, the direction of the Work Groups and the final released content of the specifications is the responsibility of the LIN Steering Committee.