UPD78F9234MC-5A4-A Datasheet, PDF (185/419 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

CHAPTER 11 SERIAL INTERFACE UART6
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 11-1 and 11-2 outline the transmission and reception operations of LIN.
Wakeup
signal frame
Figure 11-1. LIN Transmission Operation
Synchronous
break field
Synchronous Identifier Data field Data field Checksum
field
field
field
LIN bus
TxD6
(output)
8 bits^{Note 1}
13-bit^{Note 2} SBF
transmission
55H
Data
Data
Data
Data
transmission transmissiontransmission transmissiontransmission
INTST6 ^{Note 3}
Notes 1.
2.
3.
The wakeup signal frame is substituted by 80H transmission in the 8-bit mode.
The synchronous break field is output by hardware. The output width is equal to the bit length set by
bits 4 to 2 (SBL62 to SBL60) of asynchronous serial interface control register 6 (ASICL6) (see 11.4.2
(2) (h) SBF transmission).
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.
User’s Manual U17446EJ5V0UD
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