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Usart as master device, Figure 7-15 usart lin master flow chart – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 32 USART (LIN / FIFO)

7.USART Operation

USART as master device

Figure 7-15 USART LIN master flow chart

START

TIE = 0, RIE = 0

Send Message?

Y

N

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

Send Synch Break:

Send Sleep Mode?Y

N

Send Identify Field:
TDR = Id

Write to slave?

Y

N

TIE = 0
RIE = 1
Read data from slave
RIE = 0

Write data to slave
TIE = 0

TIE = 1

Errors occurred?

Y

N

Error Handler

Send Sleep Mode
TDR = 0x80

Wake up
from CPU?

Y

N

RIE = 1

TIE = 0

0x00, 0x80,

or 0xC0

N

Y

RIE = 0

Send Wake up signal
RIE = 0
TIE = 1
TDR = 0x80

received?

write "1" to ECCR:
LBR; TIE = 1;

TDRE = 1
Transm. Interrupt

Send Synch Field:
TDR = 0x55