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Usart as slave device, Figure 7-16 usart lin slave flow chart (part1) – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 32 USART (LIN / FIFO)

7.USART Operation

USART as slave device

Figure 7-16 USART LIN slave flow chart (part1)

START

Initialization:
Set Operat. mode 3
(8N1 data format)

waiting

Awaiting message

LBD = 1

LIN break interrupt

A

A

Errors occurred? Y

N

Y

N

0x80 received?
(sleep mode)

B

B

Y

N

Slave address
match?

C

C

RIE = 0; LBIE = 1; RXE = 0

Y

N

Master wants to
send data?

Receive data
+ checksum

RIE = 0
TIE = 1
Calculate
checksum
Send data

TIE = 0

C

Errors occurred? Y

N

C

Error handler

C

E

continued next page

S

(on next page)

(slave
action)

from LIN master.
Write "0" to LBD

waiting

(slave
action)

to clear interrupt.

waiting

(slave
action)

ICU -

E

Enable ICU inter-
rupt (both edges)

ICU -
Interrupt

Read ICU value
and store it.
Clear Interrupt.

Read ICU value.
Calculate new
baud rate.
Set it to Reload
Counter.
Clear Interrupt.

Interrupt

waiting

action)

(slave

Wait for Bus Idle

RBI -
Interrupt

BIE = 1

Receive Indenti-
fier.
RIE = 1,
RXE = 1