CMS32L051 User Manual |Chapter 12 Universal Serial Communication Unit
www.mcu.com.cn 439 / 703
Figure 12-116 LIN reception
Note is only required during sleep.
LIN communication starts
wait for wake up signal
frame.
NOTE.
Yes
No
Yes
LIN Bus signal state and hardware operation.
measurement low voltage width
measure mode activated TM03
INTTM03 occurs?
length >= 11 bits?
modify TM03 to measurement pulse
interval
INTTM03 occurs?
Yes
Yes
No
No
INTTM03 occurs?
INTTM03 occurs?
accumulated cpature value
4 times completion?
modify TM03 to measurement low
votlage width
calculate baud rate
UART0 initial configuration
start UART0 receiving (1->SS01 bit)
data reception
all data reception completed?
stop UART0(1->ST01 bit)
LIN communication ends
No
Yes
No
No
Yes
Yes
Yes
No
measure RxD0 Signal low voltage
width via TM03, detect BF.
Wait SBF detection.
wait BF detection.
If length >=11 bits, then consider
as BF.
configure as interval of
measurement falling edges
ignore 1st INTTM03.
measure SF 5th falling edge
interval, accumulate 4 times
capture value.
modify TM03 to measure low voltage width in order to
measure interval field.
divide accumulated result by 8, get bit width.
Determine SPS0, SDR00 and SDR01 configuration value
based on this value.
perform initial configuration of UART0 based on LIN
communication requriements.
receiving ID, data and checksum field (process while same ID
encounters)
RxD0 pin
INTP0
wake up signal
frame
edge detection
RxD0 pin
Timer40
channel 3
INTTM03
interval field
measurement
pulse width
channel 3
RxD0 pin
Timer40
channel 3
INTTM03
sync field
accumulated 4
times
measurement
pulse width
To Next Page
Loading...