E202075_HD404889 Datasheet, PDF (119/202 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

State
MCU reset
PMR3 write
SMR1 write
SMR2 write
SRL, SRU write
STS instruction
SCK pin (input)
SO pin
HD404889/HD404899/HD404878/HD404868 Series
Serial clock
wait state
STS wait state
Transfer state
Serial clock
wait state
STS wait state
Port setting
External clock setting
Idle H/L setting
Transmit data write
Dummy write to
cause state transition
Idle H/L setting
Undefined
Idle
LSB
MSB
Idle
IFS
(1) External clock mode
(Flag reset by transfer
completion processing)
State
MCU reset
PMR3 write
SMR1 write
SMR2 write
SRL, SRU write
STS instruction
SCK pin (output)
SO pin
Serial clock
wait state
STS wait state
Transfer state
Port setting
External clock setting
Idle H/L setting
Transmit data write
Undefined
Idle
LSB
STS wait state
Idle H/L setting
MSB
Idle
IFS
(2) Internal clock mode
(Flag reset by transfer
completion processing)
Figure 64 Examples of Serial Interface Operation Sequence
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