R8C/18 Group, R8C/19 Group
3. Memory
Rev.1.30
Apr 14, 2006
Page 16 of 233
REJ09B0222-0130
3.
Memory
3.1
R8C/18 Group
Figure 3.1 is a Memory Map of R8C/18 Group. The R8C/18 Group has 1 Mbyte of address space from
addresses 00000h to FFFFFh.
The internal ROM area is allocated lower addresses, beginning with address 0FFFFh. For example, a
16-Kbyte internal ROM is allocated addresses 0C000h to 0FFFFh.
The fixed interrupt vector table is allocated addresses 0FFDCh to 0FFFFh. They store the starting
address of each interrupt routine.
The internal RAM is allocated higher addresses, beginning with address 00400h. For example, a 1-
Kbyte internal RAM area is allocated addresses 00400h to 007FFh. The internal RAM is used not only
for storing data but also for calling subroutines and as stacks when interrupt requests are
acknowledged.
Special function registers (SFRs) are allocated addresses 00000h to 002FFh. The peripheral function
control registers are allocated here. All addresses within the SFR, which have nothing allocated are
reserved for future use and cannot be accessed by users.
Figure 3.1
Memory Map of R8C/18 Group
Undefined instruction
Overflow
BRK instruction
Address match
Single step
Watchdog timer
•
oscillation stop detection
•
voltage monitor 2
Address break
(Reserved)
Reset
Part Number
Internal ROM
Internal RAM
Size
Address 0YYYYh
FFFFFh
0FFFFh
0YYYYh
0XXXXh
00400h
002FFh
00000h
Internal ROM
Expanded area
Internal RAM
SFR
(See
4. Special Function
Registers (SFRs)
)
0FFFFh
0FFDCh
Size
Address 0XXXXh
NOTE:
1. The blank regions are reserved. Do not access locations in these regions.
R5F21184SP, R5F21184DSP, R5F21184DD, R5F21184NP
R5F21183SP, R5F21183DSP, R5F21183DD, R5F21183NP
R5F21182SP, R5F21182DSP, R5F21182DD, R5F21182NP
R5F21181SP, R5F21181DSP, R5F21181DD
16 Kbytes
12 Kbytes
8 Kbytes
4 Kbytes
0C000h
0D000h
0E000h
0F000h
1 Kbyte
768 bytes
512 bytes
384 bytes
007FFh
006FFh
005FFh
0057Fh