User`s manual
14
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. 8.2.3 Bank Control Register
8.2.10 Expansion ROM (only M37281MKH-
XXXSP/M37281EKSP)
The M37281MKH-XXXSP/M37281EKSP can use 5-bank (total 20K
bytes) expansion ROM (4K bytes each bank) by setting the bank
register.
The expansion ROM is assigned to address 1B00016 to 1FFFF16.
The contents of each bank in the expansion ROM are read by setting
the bank register and accessing addresses 100016 to 1FFF16. As the
expansion ROM is not programmable, use it as data-dedicated area.
When using the expansion ROM area, the internal ROM at addresses
100016 to 1FFF16 (extra area) is not also programmable.
Notes 1: When using the expansion ROM (BK7 = “1”), the ROM correction
function do not operate for addresses 1000
16 to 1FFF16.
2: When using the emulator MCU (M37281ERSS), as addresses 1000
16
to FFFF16 can be emulated by setting bit 7 of the bank control regis-
ter to “0,” the expansion ROM cannot be used. Addresses 2000
16 to
FFFF
16 can be emulated by setting it to “1.” The data in specified
area by the bank selection bits can be read by accessing addresses
1000
16 to 1FFF16.
3: When using the emulator MCU, the expansion ROM and the extra
area cannot be emulated by setting bit 7 of the bank control register
to “1.” Therefore, write the data to this area before using.
4: For the M37281MKH-XXXSP, fix bit 7 of the bank control register to
“1.” For M37281MAH-XXXSP and M37281MFH-XXXSP, fix the ad-
dress 00ED
16 to “0016.”
b
7
b
6
b
5
b
4
b
3
b
2
b
1
b
0
B
a
n
k
c
o
n
t
r
o
l
r
e
g
i
s
t
e
r
(
B
K
)
[
A
d
d
r
e
s
s
0
0
E
D
1
6
]
B
N
a
m
e
F
unct
i
ons
B
a
n
k
C
o
n
t
r
o
l
R
e
g
i
s
t
e
r
0
t
o
3
6, 7
B
an
k
contro
l
bits
(BK6, BK7)
B
an
k
num
b
er
i
s se
l
ecte
d
(b
an
k
11 to 15
)
B
an
k
selection bits
(BK0 to BK3)
4
,
5
Fi
x t
h
ese
bi
ts to “0.”
A
f
t
e
r
r
e
s
e
t
R
W
0
R
W
0
R
W
0
R
W
0
✕
10
11
N
ot use
d
U
se
d
U
se
d
R
e
a
d
o
u
t
f
r
o
m
e
x
t
r
a
a
r
e
a
(
p
r
o
g
r
a
m
m
a
b
l
e
)
R
e
a
d
o
u
t
t
h
e
d
a
t
a
f
r
o
m
a
r
e
a
s
p
e
c
i
f
i
e
d
b
y
t
h
e
b
a
n
k
s
e
l
e
c
t
i
o
n
b
i
t
s
R
e
a
d
o
u
t
f
r
o
m
e
x
t
r
a
a
r
e
a
(
d
a
t
a
-
d
e
d
i
c
a
t
e
d
)
b
6
B
an
k
ROM
A
d
d
r
e
s
s
1
0
0
0
1
6
l
e
v
e
l
a
c
c
e
s
s
b
7
00