MITSUBISHI MICROCOMPUTERS
M37270MF-XXXSP
M37270EF-XXXSP, M37270EFSP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER with CLOSED CAPTION DECODER
and ON-SCREEN DISPLAY CONTROLLER
MEMORY
Special Function Register (SFR) Area
The special function register (SFR) area in the zero page contains
control registers such as I/O ports and timers.
Interrupt Vector Area
The interrupt vector area contains reset and interrupt vectors.
Zero Page
The 256 bytes from addresses 0000
16
to 00FF
16
are called the zero
page area. The internal RAM and the special function registers (SFR)
are allocated to this area.
The zero page addressing mode can be used to specify memory and
register addresses in the zero page area. Access to this area with
only 2 bytes is possible in the zero page addressing mode.
RAM
RAM is used for data storage and for stack area of subroutine calls
and interrupts.
ROM
ROM is used for storing user programs as well as the interrupt vector
area.
Special Page
The 256 bytes from addresses FF00
16
to FFFF
16
are called the spe-
cial page area. The special page addressing mode can be used to
specify memory addresses in the special page area. Access to this
area with only 2 bytes is possible in the special page addressing
mode.
RAM for OSD
RAM for display is used for specifying the character codes and col-
ors to display.
ROM for OSD
ROM for display is used for storing character data.
0000
16
Zero page
SFR1 area
10000
16
10800
16
Not used
00C0
16
00FF
16
RAM
(1024 bytes)
0200
16
023F
16
0300
16
18000
16
053F
16
Not used
ROM for OSD
(14464 bytes)
SFR2 area
Not used
1567F
16
Not used
RAM for OSD (Note)
(1920 bytes)
0800
16
0FFF
16
1000
16
ROM
(60 K bytes)
FF00
16
FFDE
16
FFFF
16
Interrupt vector area
1E43F
16
Special page
1FFFF
16
Not used
Fig. 2. Memory map
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MITSUBISHI [ MITSUBISHI ELECTRIC SEMICONDUCTOR ]
