
R8C/36T-A Group
22. Hardware LIN
Under development Preliminary document
Specifications in this document are tentative and subject to change.
R01UH0240EJ0010 Rev.0.10
Page 530 of 728
Aug 05, 2011
Figure 22.7
Header Field Reception Flowchart Example (2)
Timer RJ
Set pulse width measurement to start
TSTART bit in TRJCR register
1
Timer RJ
Read the count status flag
TCSTF bit in TRJCR register
Hardware LIN
Set Synch Break detection to start
LSTART bit in LINCT register
1
Hardware LIN
Read the RXD input status flag
RXDSF bit in LINCT register
TCSTF = 1?
YES
RXDSF = 1?
YES
NO
Wait until timer RJ starts counting.
Hardware LIN
Clear the status flags
(Bus collision detection, Synch Break detection, Synch
Field measurement)
Bits B2CLR, B1CLR, and B0CLR in LINST register
1
Hardware LIN
Read the Synch Break detection flag
SBDCT bit in LINST register
SBDCT = 1?
YES
A Synch Break for the hardware LIN
is detected.
A timer RJ interrupt can be used.
When a Synch Break is detected,
timer RJ is reloaded with the initially
set count value.
Even if the duration of the input low
level is shorter than the set period,
timer RJ is reloaded with the initially
set count value. Wait until the next
low level is input.
One or two cycles of the CPU clock
are required after Synch Break
detection before the SBDCT bit is
set to 1.
If the SBE bit in the LINCT register is
set to 0 (unmasked after Synch
Break detected), timer RJ can be
used in timer mode after the SBDCT
bit in the LINST register is set to 1
and the RXDSF bit is set to 0.
Wait until the RXD input to UART0
for the hardware LIN is masked.
After writing 1 to the LSTART bit, do
not apply a low level to the RXD pin
until 1 is read from the RXDSF bit.
Otherwise, the signal applied during
this time will be input directly to
UART0.
One or two cycles of the CPU clocks
and zero or one cycle of the timer RJ
count source are required until the
RXDSF bit is set to 1 after the
LSTART bit is set to 1. After this,
input to timer RJ and UART0 is
enabled.
Zero or one cycle of the timer RJ
count source is required after timer
RJ starts counting before the TCSTF
bit is set to 1.
NO
A
B