S9S08SL8F1CTJ Datasheet, PDF (207/356 Pages) Freescale Semiconductor, Inc – provides the functional version of the on-chip modules

LIN MESSAGE
HEADER RECEIVED
VALID BREAK
N
AND SYNCH
DATA?
Y
SLIC UPDATES SLCBT
ID ARRIVING IN RX BUFFER
INTERRUPT
READ SLCSV
ERROR CODE
Y
?
N
READ ID FROM SLCID
CLEAR SLCF
INTERRUPT
READ SLCSV
PROCESS ERROR CODE:
BYTE FRAMING ERROR
CLEAR SLCF
PROCESS ERROR CODE:
IDENTIFIER-PARITY ERROR
BYTE FRAMING ERROR
CLEAR SLCF
EXIT ISR
RETURN TO
LIN BUS IDLE
ID FOR THIS
N
NODE
?
Y
SET IMSG BIT
PROCESS VALID ID
Figure 12-14. Handling LIN Message Headers
12.6.7.1 LIN Message Headers
All LIN message frame headers are comprised of three components:
• The first is the SYNCHRONIZATION BREAK (SYNCH BREAK) symbol, which is a dominant
(low) pulse at least 13 or more bit times long, followed by a recessive (high) synchronization
delimiter of at least one bit time. In LIN 2.0, this is allowed to be 10 or more bit times in length.
• The second part is called the SYNCHRONIZATION FIELD (SYNCH FIELD) and is a single byte
with value 0x55. This value was chosen as it is the only one which provides a series of five falling
(recessive to dominant) transitions on the bus.
MC9S08EL32 Series and MC9S08SL16 Series Data Sheet, Rev. 3
Freescale Semiconductor
209