M38197MA Datasheet, PDF (48/60 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS
3819 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
XCIN
XCOUT
“1” ^{“0”}
Port XC switch bit (Note 3)
Timer 1 count
XIN
XOUT Internal system clock selection bit source selection
(Note 1, 3)
bit (Note 2)
Low-speed mode
“1”
“1”
“0”
Middle/
1/2
1/4
1/2
“0”
High-speed mode
Timer 1
Main clock division ratio selection bit (Note 3)
Middle-speed mode
High-speed mode
or Low-speed mode
Main clock stop bit (Note 3)
Timing φ
(Internal clock)
QS
R
STP instruction
WIT
instruction
SQ
R
QS
R
STP instruction
Reset
Interrupt disable flag I
Interrupt request
Notes 1 : When selecting the low-speed mode, set the port XC switch bit to “1”.
2 : Refer to the structure of timer 12 mode register.
3 : Refer to the structure of CPU mode register (next page).
Fig. WA-3 Clock generating circuit block diagram
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