R8C/38T-A Group
3. Address Space
Under development Preliminary document
Specifications in this document are tentative and subject to change.
R01UH0241EJ0010 Rev.0.10
Page 18 of 730
Aug 05, 2011
3.
Address Space
3.1
Memory Map
Figure 3.1 shows the
Memory Map. The R8C/38T-A Group has a 1-Mbyte address space from addresses 00000h to
FFFFFh. Up to 32 Kbytes of the internal ROM (program ROM) is allocated at lower addresses, beginning with
address 0FFFFh. The area in excess of 32 Kbytes is allocated at higher addresses, beginning with address 10000h.
For example, a 64-Kbyte internal ROM is allocated at addresses 08000h to 17FFFh.
The fixed interrupt vector table is allocated at addresses 0FFDCh to 0FFFFh. The start address of each interrupt
routine is stored here.
The internal ROM (data flash) is allocated at addresses 07000h to 07FFFh.
The internal RAM is allocated at higher addresses, beginning with address 00400h. For example, a 6-Kbyte
internal RAM is allocated at addresses 00400h to 01BFFh. The internal RAM is used not only for data storage but
also as a stack area when a subroutine is called or when an interrupt request is acknowledged.
Special function registers (SFRs) are allocated at addresses 00000h to 02FFFh and addresses 06800h to 06FFFh.
Peripheral function control registers are allocated here. All unallocated locations within the SFRs are reserved and
cannot be accessed by users.
Figure 3.1
Memory Map
0XXXXh
00000h
Internal ROM
(program ROM)
Internal RAM
SFR
Internal ROM
(data flash)
(1)
002FFh
00400h
07000h
07FFFh
0YYYYh
0FFFFh
FFFFFh
Watchdog timer, oscillation stop detection, voltage monitor
Undefined instruction
Overflow
BRK instruction
Address match
Single-step
Address break
(Reserved)
Reset
0FFFFh
0FFDCh
Internal ROM
(program ROM)
ZZZZZh
06FFFh
06800h
SFR
(2)
Notes:
1. Data flash indicates block A (1 Kbyte), block B (1 Kbyte), block C (1 Kbyte), and block D (1 Kbyte).
2. Addresses 06800h to 06FFFh are used for the ELC, DTC, and TSCU SFR areas.
3. The blank areas are reserved. No access is allowed.
Part Number
Capacity
Address 0YYYYh
Internal ROM
Address 0XXXXh
Capacity
Internal RAM
Address ZZZZZh
64 Kbytes
96 Kbytes
128 Kbytes
08000h
17FFFh
1FFFFh
27FFFh
01BFFh
023FFh
02BFFh
6 Kbytes
8 Kbytes
10 Kbytes
R5F21388SNFP, R5F21388SDFP