Lin Transmission Operation - NEC 78K0 User Manual

Remark LIN stands for Local Interconnect Network and is a low-speed (1 to 20 kbps) serial communication
protocol intended to aid the cost reduction of an automotive network.
LIN communication is single-master communication, and up to 15 slaves can be connected to one
master.
The LIN slaves are used to control the switches, actuators, and sensors, and these are connected to the
LIN master via the LIN network.
Normally, the LIN master is connected to a network such as CAN (Controller Area Network).
In addition, the LIN bus uses a single-wire method and is connected to the nodes via a transceiver that
complies with ISO9141.
In the LIN protocol, the master transmits a frame with baud rate information and the slave receives it and
corrects the baud rate error. Therefore, communication is possible when the baud rate error in the slave
is ±15% or less.
Figures 15-1 and 15-2 outline the transmission and reception operations of LIN.
Wakeup
signal frame
Sleep
bus
Note 1
8 bits
TX6
INTST6
Notes 1. The wakeup signal frame is substituted by 80H transmission in the 8-bit mode.
2. The synchronous break field is output by hardware.
generator control register 6 (BRGC6) (see 15.4.2 (h) SBF transmission).
3. INTST6 is output on completion of each transmission. It is also output when SBF is transmitted.
Remark The interval between each field is controlled by software.
CHAPTER 15 SERIAL INTERFACE UART6
Figure 15-1. LIN Transmission Operation
Synchronous Synchronous
break field field
Note 2
13-bit SBF
55H
transmission
transmission
*
Note 3
User's Manual U15947EJ2V0UD
Indent Data field Data field Checksum
field
Data Data Data
transmission transmission transmission
The output width is adjusted by baud rate
field
Data
transmission
321