M37221M6_03 Datasheet, PDF (8/62 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER with ON-SCREEN DISPLAY CONTROLLER

MITSUBISHI MICROCOMPUTERS
M37221M6-XXXSP
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER for VOLTAGE SYNTHESIZER
with 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.
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.
RAM for Display
RAM for display is used for specifying the character codes and col-
ors to display.
ROM for Display
ROM for display is used for storing character data.
Interrupt Vector Area
The interrupt vector area contains reset and interrupt vectors.
Zero Page
The 256 bytes from addresses 000016 to 00FF16 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.
Special Page
The 256 bytes from addresses FF0016 to FFFF16 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.
000016
RAM
(384 bytes)
00C016
00FF16
01BF16
RAM
for display (Note)
(96 bytes)
060016
06B716
A00016
SFR area
Not used
Not used
Zero page
1000016
ROM
for display
(8 K bytes)
11FFF16
Not used
ROM
(24 K bytes)
Fig. 2. Memory map
FF0016
FFDE16
Interrupt vector area
FFFF16
Special page
1FFFF16
Note: Refer to Table 11. Contents of CRT display RAM.
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