M30218 Datasheet, PDF (9/179 Pages) Mitsubishi Electric Semiconductor – M30218 Group

Memory
Mitsubishi microcomputers
M30218 Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Operation of Functional Blocks
The M30218 group accommodates certain units in a single chip. These units include ROM and RAM to
store instructions and data and the central processing unit (CPU) to execute arithmetic/logic operations.
Also included are peripheral units such as timers, FLD controller, serial I/O, D-A converter, DMAC, CRC
calculation circuit, A-D converter, and I/O ports.
The following explains each unit.
Memory
Figure BA-1 is a memory map of the M30218 group. The address space extends the 1M bytes from ad-
dress 0000016 to FFFFF16. From FFFFF16 down is ROM. For example, in the M30218MC-AXXXFP, there
is 128K bytes of internal ROM from E000016 to FFFFF16. The vector table for fixed interrupts such as the
reset are mapped to FFFDC16 to FFFFF16. The starting address of the interrupt routine is stored here. The
address of the vector table for timer interrupts, etc., can be set as desired using the internal register (INTB).
See the section on interrupts for details.
From 0040016 up is RAM. For example, in the M30218MC-AXXXFP, there is 12K bytes of internal RAM
from 0040016 to 033FF16. In addition to storing data, the RAM also stores the stack used when calling
subroutines and when interrupts are generated. (From 0040016 to 004FF16 is RAM for SIO2. From 0050016
to 005DF16 is RAM for FLD.)
The SFR area is mapped to 0000016 to 003FF16. This area accommodates the control registers for periph-
eral devices such as I/O ports, A-D converter, serial I/O, and timers, etc. Any part of the SFR area that is not
occupied is reserved and cannot be used for other purposes.
The special page vector table is mapped to FFE0016 to FFFDB16. If the starting addresses of subroutines
or the destination addresses of jumps are stored here, subroutine call instructions and jump instructions
can be used as 2-byte instructions, reducing the number of program steps.
0000016
SFR area
(For details, see
Figures BA-2 and BA-3)
0040016 _{RAM area for SI/O2}
0050016
005E016
RAM area for FLD
(224 bytes)
Internal RAM area
YYYYY16
Type No. ^{Address Address}
XXXXX16 YYYYY16
M30218MC _E000016
M30218FC
033FF16
M30217MA E800016 017FF16
XXXXX16
Internal ROM area
FFFFF16
Figure BA-1. Memory map
FFE0016
Special page
vector table
FFFDC16
Undefined instruction
Overflow
BRK instruction
Address match
Single step
Watchdog timer
DBC
FFFFF16
Reset
8