Rev.2.00 Oct 16, 2006 page 331 of 354
REJ09B0340-0200
M30245 Group
4. External Buses
4.2 Data Access
4.2.1 Data Bus Width
If the voltage level input to the BYTE pin is “H”, the external data bus width becomes 8 bits, and P1
0
(/D
8
)
through P1
7
(/D
15
) can be used as I/O ports (Figure 4.2.1).
If the voltage level input to the BYTE pin is “L”, the external data bus width becomes 16 bits, and P0
0
(/D
0
)
through P0
7
(/D
7
), and P1
0
(/D
8
) through P1
7
(/D
15
) operate as a data bus (D
0
through D
15
) (Figure 4.2.1).
Figure 4.2.1. Level of BYTE pin and external data bus width
B
u
s
w
i
d
t
h
:
8
-
b
i
t
(
B
Y
T
E
=
“
H
”
)
M
i
c
r
o
c
o
m
p
u
t
e
r
P0
0
to P0
7
E
x
t
e
r
n
a
l
d
e
v
i
c
e
D
a
t
a
b
u
s
D
0
t
o
D
7
P1
0
to P1
7
P2
0
to P2
7
P3
0
to P3
7
P4
0
to P4
3
P4
4
to P4
7
P5
0
to P5
2
P5
3
to P5
7
I
/
O
p
o
r
t
A
d
d
r
e
s
s
b
u
s
A
0
t
o
A
1
5
A
d
d
r
e
s
s
b
u
s
A
1
6
t
o
A
1
9
(
N
o
t
e
1
)
C
h
i
p
s
e
l
e
c
t
C
S
0
t
o
C
S
3
(
N
o
t
e
2
)
R
D
,
W
R
L
,
W
R
H
/
R
D
,
B
H
E
,
W
R
(
N
o
t
e
3
)
B
C
L
K
,
H
L
D
A
,
H
O
L
D
,
A
L
E
,
R
D
Y
N
o
t
e
1
:
C
a
n
b
e
s
w
i
t
c
h
e
d
t
o
I
/
O
p
o
r
t
u
s
i
n
g
t
h
e
p
o
r
t
P
4
0
t
o
P
4
3
f
u
n
c
t
i
o
n
s
e
l
e
c
t
b
i
t
s
o
f
p
r
o
c
e
s
s
o
r
m
o
d
e
r
e
g
i
s
t
e
r
0
(
a
d
d
r
e
s
s
0
0
0
4
1
6
)
.
N
o
t
e
2
:
W
h
e
n
r
e
s
e
t
,
o
n
l
y
C
S
0
o
u
t
p
u
t
s
a
c
h
i
p
s
e
l
e
c
t
s
i
g
n
a
l
.
C
S
1
t
h
r
o
u
g
h
C
S
3
b
e
c
o
m
e
i
n
p
u
t
p
o
r
t
s
.
I
/
O
p
o
r
t
s
c
a
n
b
e
s
w
i
t
c
h
e
d
u
s
i
n
g
t
h
e
C
S
i
o
u
t
p
u
t
e
n
a
b
l
e
b
i
t
o
f
t
h
e
c
h
i
p
s
e
l
e
c
t
c
o
n
t
r
o
l
r
e
g
i
s
t
e
r
(
a
d
d
r
e
s
s
0
0
0
8
1
6
)
.
N
o
t
e
3
:
T
h
e
f
e
a
t
u
r
e
c
a
n
b
e
s
w
i
t
c
h
e
d
u
s
i
n
g
t
h
e
R
/
W
m
o
d
e
s
e
l
e
c
t
b
i
t
o
f
p
r
o
c
e
s
s
o
r
m
o
d
e
r
e
g
i
s
t
e
r
0
(
a
d
d
r
e
s
s
0
0
0
4
1
6
)
.
B
u
s
w
i
d
t
h
:
1
6
-
b
i
t
(
B
Y
T
E
=
“
L
”
)
M
i
c
r
o
c
o
m
p
u
t
e
r
P0
0
to P0
7
E
x
t
e
r
n
a
l
d
e
v
i
c
e
D
a
t
a
b
u
s
D
0
t
o
D
7
P1
0
to P1
7
P2
0
to P2
7
P3
0
to P3
7
P4
0
to P4
3
P4
4
to P4
7
P5
0
to P5
2
P5
3
to P5
7
D
a
t
a
b
u
s
D
8
t
o
D
1
5
A
d
d
r
e
s
s
b
u
s
A
0
t
o
A
1
5
A
d
d
r
e
s
s
b
u
s
A
1
6
t
o
A
1
9
(
N
o
t
e
1
)
C
h
i
p
s
e
l
e
c
t
C
S
0
t
o
C
S
3
(
N
o
t
e
2
)
RD,WRL,WRH / RD,BHE,WR (Note 3)
BCLK, HLDA, HOLD, ALE, RDY
Содержание M16C FAMILY
Страница 12: ...Chapter 1 Hardware...
Страница 13: ...See M30245 group datasheet...
Страница 14: ...Chapter 2 Peripheral Functions Usage...
Страница 303: ...THIS PAGE IS BLANK FOR REASONS OF LAYOUT...
Страница 304: ...Chapter 3 Examples of Peripheral Functions Applications...
Страница 340: ...Chapter 4 External Buses...
Страница 361: ...THIS PAGE IS BLANK FOR REASONS OF LAYOUT...
Страница 362: ...Chapter 5 Standard Characteristics...
Страница 369: ...1753 Shimonumabe Nakahara ku Kawasaki shi Kanagawa 211 8668 Japan M30245 Group REJ09B0340 0200 User s Manual...