M37212 Mitsubishi, M37212 Datasheet - Page 73

• Manufacturer Part Number: M37212
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
• Manufacturer: Mitsubishi

8.12. RESET CIRCUIT
When the oscillation of a quartz-crystal oscillator or a ceramic reso-
nator is stable and the power source voltage is 5 V
RESET pin at LOW for 2 s or more, then return is to HIGH. Then, as
shown in Figure 8.12.2, reset is released and the program starts form
the address formed by using the content of address FFFF
high-order address and the content of the address FFFE
low-order address. The internal state of microcomputer at reset are
shown in Figures 8.2.3 to 8.2.6.
An example of the reset circuit is shown in Figure 8.12.1.
The reset input voltage must be kept 0.6 V or less until the power
source voltage surpasses 4.5 V.
Fig. 8.12.2 Reset Sequence
Rev. 1.0
X
R E S E T
I n t e r n a l R E S E T
S Y N C
A d d r e s s
D a t a
I N
c l o c k c y c l e ( S e e n o t e 3 )
3 2 7 6 8 c o u n t o f X
M37212M4/M8–XXXSP, M37212M6–XXXSP/FP
I N
?
?
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
?
10 %, hold the
?
0 1 , S
16
16
as the
as the
?
0 1 , S - 1 0 1 , S - 2
N o t e s 1 : f ( X
?
2 : A q u e s t i o n m a r k ( ? ) i n d i c a t e s a n u n d e f i n e d s t a t e t h a t
3 : I m m e d i a t e l y a f t e r a r e s e t , t i m e r 3 a n d t i m e r 4 a r e
Fig. 8.12.1 Example of Reset Circuit
?
d e p e n d s o n t h e p r e v i o u s s t a t e .
c o n n e c t e d b y h a r d w a r e . A t t h i s t i m e , “ F F
i n t i m e r 3 a n d “ 0 7
w i t h f ( X
o v e r f l o w s i g n a l .
F F F E
P o w e r s o u r c e v o l t a g e 0 V
I N
A D
) a n d f ( ) a r e i n t h e r e l a t i o n : f ( X
R e s e t i n p u t v o l t a g e 0 V
L
I N
F F F F
) / 1 6 , a n d r e s e t s t a t e i s r e l e a s e d b y t h e t i m e r 4
A D
H
A D
A D
1 6
with ON-SCREEN DISPLAY CONTROLLER
H
L
,
” i s s e t t o t i m e r 4 . T i m e r 3 c o u n t s d o w n
MITSUBISHI MICROCOMPUTERS
M 5 1 9 5 3 A L
R e s e t a d d r e s s f r o m t h e v e c t o r t a b l e
1
3
M37212EFSP/FP
5
4
0 . 1 F
I N
P o w e r o n
) = 2 · f ( ) .
1 6
” i s s e t
0 . 6 V
4 . 5 V
M i c r o c o m p u t e r
V c c
R E S E T
V s s
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