BAT32G1x9 user manual | Chapter 19 Universal serial communication unit
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Rev.1.02
A summary of the receive operation of LIN is shown in Figure 19-114.
Figure 19-114 The receive operation of LIN
wake up
signal frame
interval field
sync field
identifier
data field
checksum
data field
BF reception
SF reception
ID reception
Stop
stop receiving
Stop
measurement pulse width
measurement
pulse width
measurement
pulse width
edge detection
(INTP0)
Data
reception
Data
reception
Data
reception
header
information
The flow of signal processing is as follows:
(1) Detect the wake-up signal by detecting the interrupt edge of the detection pin (INTP0). When a
wake-up signal is detected, to measure the low level width of BF, set TM03 to measure pulse
width, and then enter the BF receive waiting state.
(2) If the falling edge of BF is detected, the TM03 begins to measure the low level width and snaps
on the rising edge of BF. Based on the captured value, it is a BF signal.
(3) When the BF reception ends normally, TM03 must be set to measure the pulse interval and the
interval at which the RxD0 signal drops in the 4 sync segments must be measured (cf. "5." .8.4
Operation as input pulse interval measurement").
(4) Calculate the baud rate error according to the bit spacing of the synchronization segment (SF).
The baud rate must then be adjusted (reset) after the UART0 run is paused.
(5) Must pass the software area branch check section. UART0 must also be initialized by software
after receiving the checksum segment and set again to the BF receive wait state.