M38197 Mitsubishi, M38197 Datasheet - Page 45

• Manufacturer Part Number: M38197
• Description: SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
• Manufacturer: Mitsubishi

RESET CIRCUIT
To reset the microcomputer, RESET pin should be held at an “L”
level for 2 s or more. Then the RESET pin is returned to an “H”
level (the power source voltage should be between 2.8 V and 5.5
V, and X
the X
until after about 4000 X
completed. After the reset is completed, the program starts from
the address contained in address FFFD
dress FFFC
is 0.5 V or less for 2.8 V of V
Fig. VB-2 Reset sequence
X
RESET
Internal reset
Address
Data
SYNC
IN
IN
clock time to stabilize, internal operation does not begin
IN
oscillation is stable), reset is released. In order to give
16
(low-order). Make sure that the reset input voltage
IN
clock cycles (256 cycles of f(X
CC
X
IN
about 4000
.
clock cycles
?
16
(high-order) and ad-
Notes 1 :
?
2 :
?
f(X
A question mark (?) indicates an undefined state that depends on the previous state.
IN
IN
)/16) are
?
) and f( ) are in the relationship : f(X
?
?
Fig. VB-2 Example of reset circuit
?
?
RESET
RESET
FFFC
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
AD
IN
V
V
L
) = 8
CC
CC
FFFD
MITSUBISHI MICROCOMPUTERS
•
f( )
Power source
Reset input
Note : Reset release voltage : V
0 V
0 V
AD
voltage
voltage
H
AD
H
, AD
L
Power source voltage
detection circuit
Poweron
3819 Group
(Note)
0.2V
Reset address from
vector table
CC
CC
= 2.8 V
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