Fujitsu FR81S User Manual
CHAPTER 40: MULTI-FUNCTION SERIAL INTERFACE
7. Operation of LIN Interface (v2.1)
FUJITSU SEMICONDUCTOR LIMITED
CHAPTER : MULTI-FUNCTION SERIAL INTERFACE
FUJITSU SEMICONDUCTOR CONFIDENTIAL
320
Slave operation
Figure 7-77 Example of a Flowchart in LIN Communication Slave Mode
(Assist mode, without Using FIFO)
start
ID register use ?
YES(use)
LAMRID = reception ID Field value
RDR,LAMRID = reception ID Field value
LIN Break Field reception ?
YES
Sync Field reception ?
LIN checksum type setting(LAMCR:LCSTYP)
LIN Data length setting(LAMCR:LDL3-0)
No Framing error, overrun error,
ID parity error ?
YES
NO
Reception ID value reading
Initial setting 2:
LIN automatic header complete interrupt enable(LAMIER:LAHCIE=1), transmission bus idle interrupt disable(SCR:TBIE=0),
LIN checksum operation complete interrupt enable(LAMIER:LCSCIE=1), reception operation disable(SCR:RXE=0),
reception interrupt disable(SCR:RIE=0), transmission operation disable(SCR:TXE=0), transmission interrupt disable(SCR:TIE=0)
Initial setting 1:
operation mode 3 setting(SMR:MD2-0=3), slave mode setting(SMR:MS=1), serial data output enable(SMR:SOE=1),
operation mode 3 setting(SMR:MD2-0=3), slave mode setting(SMR:MS=1), serial data output enable(SMR:SOE=1),
baud rate setting(BGR), LIN Break interrupt disable(ESCR:LBIE=0), Sync Field interrupt disable(SACSR:SFDE=0),
serial timer disable
*1
(SACSR:TMRE=0), automatic baud rate adjustment enable
*1
(
SACSR:AUTE=1), Sync Field upper limit/lower limit value setting
*1
(
SFUR、SFLR)
LIN assist mode processing enable(LAMCR:LAMEN=1), LIN ID register use setting(LAMCR:LIDEN)
ID Field reception ?
YES
LAMSR:LAHC=1 LIN automatic header complete
YES
Automatic baud rate adjustment processing
Header processing
Response processing
Data reception ?
YES(reception)
NO(transmission)
Interrupt clear(LAMSR:LAHC=0)
*1:setting order is necessary for register setting.
[Procedure]
①
<initial value>
②
Sync Field upper limit/lower limit value setting(SFUR、SFLR)
③
automatic baud rate adjustment setting(SACSR:AUTE)
④
serial timer enable setting(SACSRTMRE)
No LIN Sync Data error,
Framing error ?
YES
NO
NO
NO
NO
NO
LIN Break Field
reception ?
NO
LIN Break Field
reception ?
YES
YES
NO
YES
LIN Break Field
reception ?
LIN Break reception
processing(B)
(Note)
Detect and properly handle errors in each process.
NO
YES
LIN Break Field
reception ?
LIN Break reception
processing(C)
YES
LIN Break Field
reception ?
LIN Break reception
processing(A)
YES
LIN Break Field
reception ?
LIN Break reception
processing(A)
NO
YES
LIN Break Field
reception ?
LIN Break reception
processing(C)
NO
YES
LIN Break Field
reception ?
LIN Break reception
processing(C)
NO
NO
NO
Data N reception(RDR)
Reception setting
(
SCR:RXE=1、SCR:RIE=1、 SCR:TXE=0、SCR:TIE=0)
LDL = 0 ?
NO
YES
No Framing error,
Overrun error ?
Data reception complete ?
NO
NO
YES
YES
LDL=reception data length ?
Reception data N reading(RDR)
SSR:RDRF=1
Reception
interrupt
NO
Checksum reception complete ?
No framing error,
overrun error ?
NO
NO
YES
YES
YES
Reception complete
(
SCR:RXE=0、SCR:RIE=0)
Interrupt clear (LAMSR:LCSC=0)
LAMSR:LCSC=1
Status interrupt
No framing error , overrun error,
checksum error ?
NO
YES
LIN assist mode status register
reading(LAMSR)
interrupt
interrupt
interrupt
interrupt
Transmission setting
(
SCR:TXE=1、SCR:TIE=1、 SCR:RXE=0、SCR:RIE=1)
LDL = 0 ?
NO
Transmission data M setting(TDR)
SSR:TDRE=1
Transmission
interrupt
YES
Data transmission start?
NO
LDL=transmission data length ?
YES
NO
No LIN bus error,
Framing error ?
NO
YES
No LIN bus error,
Framing error ?
Checksum transmission complete ?
NO
YES
LAMSR:LCSC=1
Status interrupt
YES
No LIN bus error, framing error,
Checksum error ?
NO
YES
Transmission complete
(
SCR:TXE=0、SCR:TIE=0、SCR:RIE=0)
Interrupt clear(LAMSR:LCSC=0)
SSR:TDRE=1
transmission interrupt
NO
Transmission interrupt disable(SCR:TIE=0)
YES
LIN assist mode status register
reading(LAMSR)
interrupt
interrupt
Software process
Hardware processing
Mark explanation
Error processing
Error processing
Error processing
Error processing
Error processing
Error processing
Error processing
Error processing
LIN Break reception processing(A)
Reception disable
(
SCR:RXE=0、SCR:RIE=0)
Reception data(RDR)clear
(
RDR reading)
start
end
LIN Break reception processing(C)
Transmission disable
(
SCR:TXE=0、SCR:TIE=0)
Transmission data(TDR)clear
(
LAMCR:LTDRCL=1)
start
end
LIN Break reception processing(B)
Reception disable
(
SCR:RXE=0、SCR:RIE=0)
start
end
MB91520 Series
MN705-00010-1v0-E
1633