CHAPTER 3 CPU FUNCTIONS
73
Application of wrap-around
For example, when R = r0 (zero register) is specified for the LD/ST disp16 [R] instruction, an addressing range of
00000000H ± 32 Kbytes can be referenced with the sign-extended, 16-bit displacement value. By mapping the
external memory in the 24-Kbyte area in the figure, all resources including on-chip hardware can be accessed
with one pointer.
The zero register (r0) is a register set to 0 by the hardware, and eliminates the need for additional registers for the
pointer.
Internal
ROM area
On-chip peripheral I/O area
External memory
area
Internal RAM area
4 KB
4 KB
24 KB
0001FFFFH
00007FFFH
0001FFFFH
00007FFFH
(R = ) 00000000H
FFFFF000H
FFFFC000H
(R = ) 00000000H
FFFFF000H
FFFFE000H
FFFF8000H
FFFF8000H
Internal ROM
area
Internal RAM
area
External memory
area
On-chip peripheral I/O area
32 KB
32 KB
4 KB
12 KB
16 KB
Flash memory internal version
Mask ROM internal version
Содержание V850/SA1 mPD703015
Страница 2: ...2 MEMO ...
Страница 100: ...100 MEMO ...
Страница 144: ...144 MEMO ...
Страница 200: ...200 MEMO ...
Страница 328: ...328 MEMO ...
Страница 356: ...356 MEMO ...
Страница 358: ...358 MEMO ...
Страница 368: ...368 MEMO ...
Страница 374: ...374 MEMO ...
Страница 382: ...382 MEMO ...