
18
3886 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
Fig. 14 Structure of port I/O related register
P
o
r
t
c
o
n
t
r
o
l
r
e
g
i
s
t
e
r
1
b
7b
0
P
o
r
t
c
o
n
t
r
o
l
r
e
g
i
s
t
e
r
2
P
0
0
–
P
0
3
o
u
t
p
u
t
s
t
r
u
c
t
u
r
e
s
e
l
e
c
t
i
o
n
b
i
t
0
:
C
M
O
S
1
:
N
-
c
h
a
n
n
e
l
o
p
e
n
-
d
r
a
i
n
P
0
4
–
P
0
7
o
u
t
p
u
t
s
t
r
u
c
t
u
r
e
s
e
l
e
c
t
i
o
n
b
i
t
0
:
C
M
O
S
1
:
N
-
c
h
a
n
n
e
l
o
p
e
n
-
d
r
a
i
n
P
1
0
–
P
1
3
o
u
t
p
u
t
s
t
r
u
c
t
u
r
e
s
e
l
e
c
t
i
o
n
b
i
t
0
:
C
M
O
S
1
:
N
-
c
h
a
n
n
e
l
o
p
e
n
-
d
r
a
i
n
P
1
4
–
P
1
7
o
u
t
p
u
t
s
t
r
u
c
t
u
r
e
s
e
l
e
c
t
i
o
n
b
i
t
0
:
C
M
O
S
1
:
N
-
c
h
a
n
n
e
l
o
p
e
n
-
d
r
a
i
n
P
3
0
–
P
3
3
p
u
l
l
-
u
p
c
o
n
t
r
o
l
b
i
t
0
:
N
o
p
u
l
l
-
u
p
1
:
P
u
l
l
-
u
p
P
3
4
–
P
3
7
p
u
l
l
-
u
p
c
o
n
t
r
o
l
b
i
t
0
:
N
o
p
u
l
l
-
u
p
1
:
P
u
l
l
-
u
p
P
W
M
0
e
n
a
b
l
e
b
i
t
0
:
P
W
M
0
o
u
t
p
u
t
d
i
s
a
b
l
e
d
1
:
P
W
M
0
o
u
t
p
u
t
e
n
a
b
l
e
d
P
W
M
1
e
n
a
b
l
e
b
i
t
0
:
P
W
M
1
o
u
t
p
u
t
d
i
s
a
b
l
e
d
1
:
P
W
M
1
o
u
t
p
u
t
e
n
a
b
l
e
d
P
4
i
n
p
u
t
l
e
v
e
l
s
e
l
e
c
t
i
o
n
b
i
t
(
P
4
2
–
P
4
6
)
0
:
C
M
O
S
l
e
v
e
l
i
n
p
u
t
1
:
T
T
L
l
e
v
e
l
i
n
p
u
t
P
7
i
n
p
u
t
l
e
v
e
l
s
e
l
e
c
t
i
o
n
b
i
t
(
P
7
0
–
P
7
5
)
0
:
C
M
O
S
l
e
v
e
l
i
n
p
u
t
1
:
T
T
L
l
e
v
e
l
i
n
p
u
t
P
4
o
u
t
p
u
t
s
t
r
u
c
t
u
r
e
s
e
l
e
c
t
i
o
n
b
i
t
(
P
4
2
,
P
4
3
,
P
4
4
,
P
4
6
)
0
:
C
M
O
S
1
:
N
-
c
h
a
n
n
e
l
o
p
e
n
-
d
r
a
i
n
P
8
f
u
n
c
t
i
o
n
s
e
l
e
c
t
i
o
n
b
i
t
0
:
P
o
r
t
P
8
/
P
o
r
t
P
8
d
i
r
e
c
t
i
o
n
r
e
g
i
s
t
e
r
1
:
P
o
r
t
P
4
i
n
p
u
t
r
e
g
i
s
t
e
r
/
P
o
r
t
P
7
i
n
p
u
t
r
e
g
i
s
t
e
r
I
N
T
2
,
I
N
T
3
,
I
N
T
4
i
n
t
e
r
r
u
p
t
s
w
i
t
c
h
b
i
t
0
:
I
N
T
2
0
,
I
N
T
3
0
,
I
N
T
4
0
i
n
t
e
r
r
u
p
t
1
:
I
N
T
2
1
,
I
N
T
3
1
,
I
N
T
4
1
i
n
t
e
r
r
u
p
t
T
i
m
e
r
Y
c
o
u
n
t
s
o
u
r
c
e
s
e
l
e
c
t
i
o
n
b
i
t
0
:
f
(
X
I
N
)
/
1
6
(
f
(
X
C
I
N
)
/
1
6
i
n
l
o
w
-
s
p
e
e
d
m
o
d
e
)
1
:
f
(
X
C
I
N
)
O
s
c
i
l
l
a
t
i
o
n
s
t
a
b
i
l
i
z
i
n
g
t
i
m
e
s
e
t
a
f
t
e
r
S
T
P
i
n
s
t
r
u
c
t
i
o
n
r
e
l
e
a
s
e
d
b
i
t
1
:
N
o
a
u
t
o
m
a
t
i
c
s
e
t
P
o
r
t
o
u
t
p
u
t
P
4
2
/
P
4
3
c
l
e
a
r
f
u
n
c
t
i
o
n
s
e
l
e
c
t
i
o
n
b
i
t
0
:
O
n
l
y
s
o
f
t
w
a
r
e
c
l
e
a
r
1
:
S
o
f
t
w
a
r
e
c
l
e
a
r
a
n
d
o
u
t
p
u
t
d
a
t
a
b
u
s
b
u
f
f
e
r
0
r
e
a
d
i
n
g
(
s
y
s
t
e
m
b
u
s
s
i
d
e
)
b
7b
0
(
P
C
T
L
1
:
a
d
d
r
e
s
s
0
0
2
E
1
6
)
(
P
C
T
L
2
:
a
d
d
r
e
s
s
0
0
2
F
1
6
)
0
:
A
u
t
o
m
a
t
i
c
s
e
t
“
0
1
1
6
”
t
o
t
i
m
e
r
1
a
n
d
“
F
F
1
6
”
t
o
p
r
e
s
c
a
l
e
r
1
2
Kommentare zu diesen Handbüchern