Renesas M16C/50 Series User Manual page 163

M16C/5L Group, M16C/56 Group
9.3.2 Clock Mode Transition Procedure
Figure 9.1 shows Clock Mode Transition. Arrows indicate possible mode transitions.
Normal
Operating Mode
PLL operating mode
Figure 9.1 Clock Mode Transition
To start or stop clock oscillations, or to change modes in normal operating mode, follow the instructions
below.
•
Enter a different mode after the clock for that mode stabilizes completely.
•
When stopping a clock, do it after mode transition is completed. Do not stop the clock at the same
time as mode transition.
•
To change the mode, follow procedures listed below. For details on register and bit access, refer to
9.2 "Registers". Letters a to i correspond to those in Figure 9.1 "Clock Mode Transition".
•
For details on oscillator start and stop, refer to 8.3.1 "Main Clock" to 8.3.6 "Sub Clock (fC)".
R01UH0127EJ0110 Rev.1.10
Sep 01, 2011
40 MHz on-chip
oscillator mode
d a
a
High-speed or
c
medium-speed
b
mode
Interrupt
or
reset
Wait mode
CPU operation stop
Reset
wait mode and stop mode enabled
i
125 kHz on-chip
oscillator mode
d
e
e
f
f
Low-speed mode
a
Interrupt
WAIT or
instruction reset
All oscillations stop
9. Power Control
Transitions to
g
125 kHz on-chip
oscillator low power
h
mode
g
Low power mode
h
CM10 = 1
Stop mode
CM10 : Bit in the CM1 register
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