
35
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
38C8 Group
RESET CIRCUIT
To reset the microcomputer, RESET pin should be held at an “L”
level for 2 µs or more. Then the RESET pin is returned to an “H” level
(the power source voltage should be between VCC (min.) and 5.5 V,
and the quartz-crystal oscillator should be stable), reset is released.
After the reset is completed, the program starts from the address
contained in address FFFD16 (high-order byte) and address FFFC16
(low-order byte). Make sure that the reset input voltage is less than
0.2Vcc when a power source voltage passes VCC (min.).
Fig. 34 Reset sequence
Fig. 33 Reset circuit example
0.2VCC
0
V
0
V
P
o
w
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VC
CR
E
S
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T
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RESET
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Data
SYNC
φ
X
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FFFC F
F
F
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A
D
H
,
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AD
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(φ)
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(
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=
8
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.
2
:
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