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57
4554 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
Fig. 43 State transition
Fig. 44 Set source and clear source of the P flag
Fig. 45 Start condition identified example using the SNZP instruction
R
e
s
e
t
B
Operation state
Operation source clock: f(XIN)
Oscillation circuit:
Ceramic resonator
Ring oscillator: Stop
RC oscillation circuit: Stop
A
C
E
Clock operating mode
Main clock: stop
Sub-clock: operating
Key-on wakeup
(Stabilizing time c )
POF2 instruction
execution
F
RAM back-up mode
POF2 instruction
execution
High-speed mode
D
Operation clock: f(XCIN)
Oscillation circuit:
Quartz-crystal oscillation
MR0
←0
(Note 4)
MR0
←1
(Note 4)
Low-speed
mode
Key-on wakeup
(Stabilizing time b )
POF2 instruction
execution
Key-on wakeup
(Stabilizing time d )
POF2 instruction
execution
Key-on wakeup
(Stabilizing time e )
POF instruction
execution
Key-on wakeup
(Stabilizing time e )
POF instruction
execution
Key-on wakeup
(Stabilizing time d )
POF instruction
execution
Key-on wakeup
(Stabilizing time b )
(Stabilizing time a )
POF instruction
execution
Key-on wakeup
(Stabilizing time c )
Main clock: stop
Sub-clock: stop
CMCK instruction
execution (Note 3)
Operation state
Operation source clock:
f(RING)
Oscillation circuit:
Ring oscillator
Ceramic resonator:
Operating (Note 2)
RC oscillation circuit: Stop
CRCK instruction
execution (Note 3)
Operation state
Operation source clock: f(XIN)
Oscillation circuit:
RC oscillation
Ring oscillator: Stop
Ceramic resontor: Stop
Operation state
Stabilizing time a : Microcomputer starts its operation after counting the ring oscillator clock 5400 to 5424 times.
Stabilizing time b : In high-speed through-mode, microcomputer starts its operation after counting the f(RING) 675 times.
In high-speed/2 mode, microcomputer starts its operation after counting the f(RING) 1350 times.
In high-speed/4 mode, microcomputer starts its operation after counting the f(RING) 2700 times.
In high-speed/8 mode, microcomputer starts its operation after counting the f(RING) 5400 times.
Stabilizing time c : In high-speed through-mode, microcomputer starts its operation after counting the f(XIN) 675 times.
In high-speed/2 mode, microcomputer starts its operation after counting the f(XIN) 1350 times.
In high-speed/4 mode, microcomputer starts its operation after counting the f(XIN) 2700 times.
In high-speed/8 mode, microcomputer starts its operation after counting the f(XIN) 5400 times.
Stabilizing time d : In high-speed through-mode, microcomputer starts its operation after counting the f(XIN) 21 times.
In high-speed/2 mode, microcomputer starts its operation after counting the f(XIN) 42 times.
In high-speed/4 mode, microcomputer starts its operation after counting the f(XIN) 84 times.
In high-speed/8 mode, microcomputer starts its operation after counting the f(XIN) 168 times.
Stabilizing time e : In low-speed through-mode, microcomputer starts its operation after counting the f(XCIN) 675 times.
In low-speed/2 mode, microcomputer starts its operation after counting the f(XCIN) 1350 times.
In low-speed/4 mode, microcomputer starts its operation after counting the f(XCIN) 2700 times.
In low-speed/8 mode, microcomputer starts its operation after counting the f(XCIN) 5400 times.
Notes 1: Continuous execution of the EPOF instruction and the POF instruction is required to go into the clock operating state.
Continuous execution of the EPOF instruction and the POF2 instruction is required to go into the RAM back-up state.
2: Through the ceramic resonator is operating, the ring oscillator clock is selected as the operation source clock.
3: The oscillator clock corresponding to each instruction is selected as the operation source clock, and the ring oscillator is stopped.
4: The main clock (f(XIN) or f(RING)) or sub-clock (f(XCIN)) is selected for operation source clock by the bit 0 of clock control register MR.
S
R
Q
Power down flag P
POF or
POF2
instruction
Reset input
q Set source
q Clear source
Reset input
EPOF instruction +
POF or
POF2
instruction
EPOF instruction +
Program start
P = “1”
?
Yes
Warm start
Cold start
No
T5F = “1”
?
Yes
No
Return from
timer 5 underflow
Return from
external wakeup signal