Casio I/O-PB-12 Service Manual page 26

A B
1
2
VCC
1
3
2 3 4 5
RA1
R57
D0
R56
D1
R55
D2
R54
D3
R53
D4
R52
4
D5
R51
D6
R50
D7
R49
R48
RAMCE 1
RAMCE0
R47
IOCS
CPURST
(3/7)(4/7)
5
RAMCE
(5/7)
INT 1
INT 2
6
7
8
A B
C D E
TO E-I/O-PB-12 (1/6)
TO E-I/O-PB-12 (3/6)(4/6)(5/6)
12
D0
13
VCC
14
D1
15
D2
16
D3
17
D4
18
D5
19
GND
20
D6
21
D7
22
RAMCE1
23
RAMCE0
24
25
IOCS
26
VCC
27
CPURST
28
INT1
29
INT2
30
RAMCE
31
32
GND
C10
C11
GND VCC
TO E-I/O-PB-12 (1/6)
C D E
F G H
IC5
74
I/O4
73
I/03
72
GND
71
I/O2
70
I/O1
69
CSART
68
ARCINT
67
ARCRST
66
VCC
65
SA0
64
SA1
63
SA2
62
SD0
61
SD1
60
SD2
59
GND
58
SD3
57
SD4
56
SD5
55
SD6
54
SD7
C9
F G H
— 24 —
I J
VCC
R22 R14
VCC
C20
C21
IC4
1 24
A0 VCC
2
23
A1
RD
3
22
A2
WR
4 21 R13
D0 CS
5 20
D1 INTR
R15
6
19
D2
RST
7 18
D3
TXEN
8 17
D4 RXIN
9 16
D5
10
15
D6
TXOUT
11 14
D7
X2
12 13
GND X1
X1
C8 C7 C6
GND
Board No.
E211761
E-I/O-PB-12 (2/6)
I J
K
1
POWER
BATT
DCCUT
2
3
4
TXEN
RXIN 5
TXOUT
6
7
8
K