212 Series of Decoders
Block Diagram
O
S
C
O
2
S
C
1
O
s
c
i
l
l
a
t
D
o
i
r
v
i
d
e
r
D
a
t
a
S
h
i
f
t
D
a
t
a
u i
L
a
t
c
h
C
i
r
c
t
R
e
g
i
s
t
e
r
B
u
f
f
e
r
D
a
t
a
D
e
t
e
c
t
o
r
D
I
N
S
y
n
c
.
D
C
e
o
t
e
m
c
p
t
a
o
r
r
a
t
o
r
C
C
o
o
m
n
p
t
r
a
o
r
l
a
t
L
o
o
r
g
i
c
T
r
a
n
s
m
i
s
s
i
o
n
G
a
t
e
C
B
i
u
r
c
f
f
u
e
i
r
t
V
T
A
d
d
r
e
s
s
V
D
D
V
S
S
Note: The address/data pins are available in various combinations (see the address/data table).
Pin Assignment
8
4
-
-
A
D
d
a
d
r
e
s
s
1
2
-
A
d
d
r
e
s
s
1
2
-
A
d
d
r
e
s
s
8
4
-
-
A
D
d
a
d
r
e
s
s
t
a
0
-
D
a
t
a
0
-
D
a
t
a
t
a
N
C
2
1
1
1
1
1
1
1
1
1
0
9
8
7
6
5
4
3
2
1
N
C
2
1
1
1
1
1
1
1
1
1
0
9
8
7
6
5
4
3
2
1
N
V
V
O
O
D
D
D
D
D
C
N
V
V
O
O
D
A
A
A
A
C
I
1
2
3
4
5
6
7
8
9
1
1
2
3
4
5
6
7
8
9
1
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
8
7
6
5
4
3
2
1
0
A
A
A
A
A
A
A
A
0
1
2
3
4
5
6
7
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
8
7
6
5
4
3
2
1
0
A
A
A
A
A
A
A
A
0
1
2
3
4
5
6
7
V
V
O
O
D
D
D
D
D
D
T
D
A
A
A
A
A
A
A
A
0
1
2
3
4
5
6
7
V
V
O
O
D
A
A
A
A
D
T
D
A
A
A
A
A
A
A
A
0
1
2
3
4
5
6
7
D
T
D
D
T
D
S
S
C
C
1
2
S
S
C
C
1
2
S
S
C
C
1
2
S
S
C
C
1
2
I
1
1
9
8
N
I
N
I
1
1
9
8
N
N
1
0
1
1
9
8
1
0
1
0
1
1
9
8
1
0
V
S
S
V
S
S
V
S
S
V
S
S
0
0
H
T
1
2
D
H
T
1
2
F
H
T
1
2
D
H
T
1
2
F
2
0
S
O
P
2
0
S
O
P
1
8
D
I
P
1
8
D
I
P
2
July 12, 1999
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
