Memory
M30240 Group
Rev.1.00 Sep 24, 2003 Page 14 of 360
1.2.3 Memory
Figure 1.8: Memory Map
Figure 1.8 is a memory map of the M30240 group. The address space extends the 1M bytes from
address 00000
16
to FFFFF
16
. Addresses above yyyyy
16
are ROM. For example, in the M30240ECFP,
there is 128K bytes of internal ROM from E0000
16
to FFFFF
16
. The special page vector table is mapped
from FFE00
16
to FFFDB
16
. 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 two-byte instructions,
reducing the number of program steps.
The vector table for fixed interrupts such as the reset and NMI
are mapped from FFFDC
16
to FFFFF
16
.
The starting addresses of the interrupt routines are stored here. The address of the vector table for
software interrupts can be set as desired using the internal register (INTB). See Section 2.12 on
interrupts for further details.
Addresses below xxxxx
16
are RAM. For example, in M30240ECFP, 5K bytes of internal RAM are
mapped to the space from 00400
16
to 017FF
16
. In addition to storing data, the RAM also stores the stack
used when calling subroutines and when interrupts are generated.The SFR area is mapped to 00000
16
to 003FF
16
. This area accommodates control registers for peripheral devices such as I/O ports, A-D
converter, serial I/O, and timers. Section 2.4 describes the SFR area for peripheral unit control registers.
Any part of the SFR area that is unoccupied is reserved and cannot be used for other purposes.
yyyyy
16
Overflow
BRK instruction
Address match
Single step
Watchdog timer
Reset
00000
16
0040016
XXXXX16
ROM
unused
SFR
RAM
FFE0016
FFFDC16
FFFFF16
Undefined instruction
Special page
vector table
DBC
NMI
Type Address xxxxx
16
Address yyyyy
16
M30240M5
00FFF
16
F6000
16
M30240M6
00FFF
16
F4000
16
M30240ECFP
017FF
16
E0000
16
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