User`s manual
32
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
and ON-SCREEN DISPLAY CONTROLLER
M37281MAH–XXXSP,M37281MFH–XXXSP
M37281MKH–XXXSP,M37281EKSP
MITSUBISHI MICROCOMPUTERS
Rev. 1.0
Fig. 8.5.3 Serial I/O Mode Register
b
7b
6 b
5b
4b3 b
2b
1b
0
Serial I/O mode register (SM) [Address 0213
16
]
BN
a
m
eF
u
n
c
t
i
o
n
s
A
f
t
e
r
r
e
s
e
t
RW
S
e
r
i
a
l
I
/
O
M
o
d
e
R
e
g
i
s
t
e
r
0
,
1 Internal synchronous
clock selection bits
(SM0, SM1)
b
1
b
0
0
0
:
f
(
X
I
N
)
/
8
o
r
f
(
X
C
I
N
)
/
8
0
1
:
f
(
X
I
N
)
/
1
6
o
r
f
(
X
C
I
N
)
/
1
6
1
0
:
f
(
X
I
N
)
/
3
2
o
r
f
(
X
C
I
N
)
/
3
2
1
1
:
f
(
X
I
N
)
/
6
4
o
r
f
(
X
C
I
N
)
/
6
4
2
Synchronous clock
selection bit (SM2)
3
Port function
selection bit (SM3)
6
5
Transfer direction
selection bit (SM5)
0
:
P
1
1
,
P
1
3
1
:
S
C
L
1
,
S
D
A
1
0
:
E
x
t
e
r
n
a
l
c
l
o
c
k
1
:
I
n
t
e
r
n
a
l
c
l
o
c
k
0
:
T
r
a
n
s
f
e
r
f
r
o
m
t
h
e
l
a
s
t
s
i
g
n
i
f
i
c
a
n
t
b
i
t
(
L
S
B
)
1
:
T
r
a
n
s
f
e
r
f
r
o
m
t
h
e
t
o
p
s
i
g
n
i
f
i
c
a
n
t
b
i
t
(
M
S
B
)
0
0
0
0
0
0
RW
RW
RW
R
W
RW
RW
4
Port function
selection bit (SM4)
0
:
P
1
2
,
P
1
4
1
:
S
C
L
2
,
S
D
A
2
7
N
o
t
h
i
n
g
i
s
a
s
s
i
g
n
e
d
.
T
h
i
s
b
i
t
i
s
a
w
r
i
t
e
d
i
s
a
b
l
e
b
i
t
.
W
h
e
n
t
h
i
s
b
i
t
i
s
r
e
a
d
o
u
t
,
t
h
e
v
a
l
u
e
i
s
“
0
.
”
0R—
S
IN
pin switch bit
(SM6)
0: P1
7
is S
IN
pin
1: P7
2
is S
IN
pin