m37516e6hp Renesas Electronics Corporation., m37516e6hp Datasheet - Page 50

• Manufacturer Part Number: m37516e6hp
• Description: Single-chip 8-bit Cmos Microcomputer
• Manufacturer: Renesas Electronics Corporation.

7516 Group
Fig. 56 State transitions of system clock
Rev.1.01
N o t e s
C M
C M
C M
C M
C M
C M
C M
C M
1 : S w i t c h t h e m o d e b y t h e a l l o w s s h o w n b e t w e e n t h e m o d e b l o c k s . ( D o n o t s w i t c h b e t w e e n t h e m o d e s d i r e c t l y w i t h o u t a n a l l o w . )
2 : T h e a l l m o d e s c a n b e s w i t c h e d t o t h e s t o p m o d e o r t h e w a i t m o d e a n d r e t u r n t o t h e s o u r c e m o d e w h e n t h e s t o p m o d e o r t h e w a i t m o d e i s
3 : T i m e r o p e r a t e s i n t h e w a i t m o d e .
4 : W h e n b i t 0 o f M I S R G i s “ 0 ” a n d t h e s t o p m o d e i s e n d e d , a d e l a y o f a p p r o x i m a t e l y 1 m s o c c u r s b y c o n n e c t i n g t i m e r 1 i n m i d d l e / h i g h - s p e e d
5 : W h e n b i t 0 o f M I S R G i s “ 0 ” a n d t h e s t o p m o d e i s e n d e d , t h e f o l l o w i n g i s p e r f o r m e d .
6 : W a i t u n t i l o s c i l l a t i o n s t a b i l i z e s a f t e r o s c i l l a t i n g t h e m a i n c l o c k X
7 : T h e e x a m p l e a s s u m e s t h a t 8 M H z i s b e i n g a p p l i e d t o t h e X
Jul 01, 2003
7
6
5
4
7
6
5
4
M i d d l e - s p e e d m o d e
= 0
= 1
= 0 ( 8 M H z o s c i l l a t i n g )
= 0 ( 3 2 k H z s t o p p e d )
M i d d l e - s p e e d m o d e
= 0
= 1
= 0 ( 8 M H z o s c i l l a t i n g )
= 1 ( 3 2 k H z o s c i l l a t i n g )
( f ( ) = 1 M H z )
e n d e d .
m o d e .
( 1 ) A f t e r t h e c l o c k i s r e s t a r t e d , a d e l a y o f a p p r o x i m a t e l y 2 5 0 m s o c c u r s i n l o w - s p e e d m o d e i f T i m e r 1 2 c o u n t s o u r c e s e l e c t i o n b i t i s “ 0 ” .
( 2 ) A f t e r t h e c l o c k i s r e s t a r t e d , a d e l a y o f a p p r o x i m a t e l y 1 6 m s o c c u r s i n l o w - s p e e d m o d e i f T i m e r 1 2 c o u n t s o u r c e s e l e c t i o n b i t i s “ 1 ” .
m o d e .
( f ( ) = 1 M H z )
R e s e t
page 48 of 89
CM
“1”
CM
“1”
6
6
“0”
“0”
CM
CM
CM
CM
CM
CM
CM
CM
C M
C M
C M
C M
C M
C M
C M
C M
7
6
5
4
7
6
5
4
= 1
= 0
= 1 (8 MHz stopped)
= 1 (32 kHz oscillating)
7
6
5
4
7
6
5
4
= 0
= 0
= 0 (8 MHz oscillating)
= 1 (32 kHz oscillating)
High-speed mode
High-speed mode
= 1
= 0
= 0 ( 8 M H z o s c i l l a t i n g )
= 1 ( 3 2 k H z o s c i l l a t i n g )
Low-speed mode
= 0
= 0
= 0 ( 8 M H z o s c i l l a t i n g )
= 0 ( 3 2 k H z s t o p p e d )
L o w - s p e e d m o d e
(f( ) = 4 MHz)
(f( ) = 4 MHz)
(f( )=16 kHz)
( f ( ) = 1 6 k H z )
I N
p i n a n d 3 2 k H z t o t h e X
I N
b e f o r e t h e s w i t c h i n g f r o m t h e l o w - s p e e d m o d e t o m i d d l e / h i g h - s p e e d
b7
C I N
b 4
p i n .
CM
CM
CM
4
5
7
, CM
: Port Xc switch bit
: Main clock (X
b7 b6
i n d i c a t e s t h e i n t e r n a l c l o c k .
0 : I/O port function (stop oscillating)
1 : X
0 : Operating
1 : Stopped
0
0
1
1
6
: Main clock division ratio selection bits
0 :
1 :
0 :
1 : Not available
CIN
CPU mode register
(CPUM : address 003B
-X
= f(X
= f(X
COUT
= f(X
IN
oscillating function
IN
IN
- X
CIN
)/2 ( High-speed mode)
)/8 (Middle-speed mode)
OUT
)/2 (Low-speed mode)
) stop bit
16
)