SYNCH BREAK FIELD
SYNCH FIELD
ID FIELD
Sync Break
Sync Field
ID Field
1, 2, 3, ...8 Data Fields
Checksum
Master Header
Slave Response
Message Frame
In-frame space
Master or Slave
LIN
1643
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Serial Communication Interface (SCI)/ Local Interconnect Network (LIN)
Module
The Master Mode of LIN module is compatible with LIN 2.1 standard.
29.3.1.2 Message Frame
The LIN protocol defines a message frame format, illustrated in
. Each frame includes one
master header, one response, one in-frame response space, and inter-byte spaces. In-frame-response
and inter-byte spaces may be 0.
Figure 29-12. LIN Protocol Message Frame Format: Master Header and Slave Response
There is no arbitration in the definition of the LIN protocol; therefore, multiple slave nodes responding to a
header might be detected as an error.
The LIN bus is a single channel wired-AND. The bus has a binary level: either dominant for a value of 0,
or recessive for a value of 1.
29.3.1.2.1 Message Header
The header of a message is initiated by a master (see
) and consists of a three field-
sequence:
•
The synch break field signaling the beginning of a message
•
The synch field conveying bit rate information of the LIN bus
•
The ID field denoting the content of a message
Figure 29-13. Header 3 Fields: Synch Break, Synch, and ID