Renesas M16C FAMILY, Руководство пользователя

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Rev.2.00 Oct 16, 2006 page 279 of 354
REJ09B0340-0200
M30245 Group 2. Power Control
Figure 2.16.4. Power control-related registers
Bit Symbol Bit Name Function R W
O O
Symbol
CM0 Address
0006
16
When reset
48
16
System clock control register 0 (Note 1)
b7 b5 b6 b4 b3 b2 b1 b0
CM02
CM03
CM04
CM05
CM06
CM07
WAIT peripheral function
clock stop bit
Xcin-Xcout drive capacity
select bit (Note 2)
Port Xc select bit
Main clock (Xin-Xout)
stop bit (Note 3, 4, 5)
Main clock division select
bit 0 (Note 7)
System clock select bit
(Note 6)
0 : Do not stop in wait mode
1 : Stop in wait mode (Note 8)
0 : LOW
1 : HIGH
0 : I/O port
1 : Xcin-Xcout generation
0 : On
1 : Off
0 : CM16 and CM17 valid
1 : Divide-by-8 mode
0 : Xin, Xout
1 : Xcin, Xcout
O O
O O
O O
O O
O O
O O
Note 1: Set bit 0 of the protect register (address 000A
16
) to “1” before writing to this register.
Note 2: Changes to “1” when changing to stop mode and at a reset.
Note 3: When entering power saving mode, main clock stops using this bit. When returning from
stop mode and operating in X
IN
, set this bit to “0”. When main clock oscillation is operating
by itself, set system clock select bit (CM07) to “1” before setting this bit to “1”.
Note 4: When inputting external clock, only clock oscillation buffer is stopped and clock input is
acceptable.
Note 5: If this bit is set to “1”, X
OUT
becomes “H”. The built-in feedback resistor remains connected,
so X
IN
becomes pulled up to Xout (“H”) using the feedback resistor.
Note 6: Set port Xc select bit (CM04) to “1”, and stabilize the sub clock oscillating before setting to
this bit from “0” to “1”. Do not write to both bits at the same time. Also, set the main clock
stop bit (CM05) to “0”, and stabilize the main clock oscillating before setting this bit from
“1” to “0”.
Note 7: This bit changes to “1”, when changing from high-speed/medium mode to stop mode and at
reset. When shifting from low-speed/low power dissipation mode to stop mode, the value
before stop mode is retained.
Note 8: f
C32
is not included. Do not set to “1” when using low-speed or low power dissipation mode.
Note 9: When the X
CIN
/X
COUT
is used, set ports P8
6
and P8 7 as the input ports without pull-up.
Bit Symbol Bit Name Function R W
O O
Symbol
CM1 Address
0007
16
When reset
20
16
System clock control register 1 (Note 1)
b7 b5 b6 b4 b3 b2 b1 b0
CM10
Reserved bit
CM15
CM16
CM17
All clock stop control bit
(Note 4) 0 : Clock on
1 : All clocks off (stop mode)
Always set to “0”
0 : LOW
1 : HIGH
b7 b6
0 0 : No division mode
0 1 : Divide-by-2 mode
1 0 : Divide-by-4 mode
1 1 : Divide-by-16 mode
O O
O O
O O
O O
Xin-Xout drive capacity
select bit (Note 2)
Main clock division select
bit 1 (Note 3)
0 0 0 0
Note 1: Set bit 0 of the protect register (address 000A
16
) to “1” before writing to this register.
Note 2: This bit changes to “1”, when changing from high-speed/medium mode to stop mode and at
reset. When shifting from low-speed/low power dissipation mode to stop mode, the value
before stop mode is retained.
Note 3: Can be selected when bit 6 of the system clock control register 0 (address 0006
16
) is “0”.
If “1”, division mode is fixed at 8.
Note 4: If this bit is set to “1”, X
OUT
turns “H”, and the built-in feedback resistor is cut off. X
CIN
and
X
COUT
turn high-impedance state.
Reserved bit
Always set to “0”
0 0