CHAPTER 3 CPU FUNCTIONS
60
3.4.2 Image (virtual address space)
The core CPU supports 4 Gbytes of “virtual” addressing space, or 256 memory blocks, each containing 16-Mbyte
memory locations. In actuality, the same 16-Mbyte block is accessed regardless of the values of bits 31 to 24 of the
CPU address. Figure 3-2 shows the image of the virtual addressing space.
Because the higher 8 bits of a 32-bit CPU address are ignored and the CPU address is only seen as a 24-bit
external physical address, the physical location xx000000H is equally referenced by multiple address values
00000000H, 01000000H, 02000000H... through FE000000H, FF000000H.
Figure 3-2. Image on Address Space
FFFFFFFFH
FF000000H
FEFFFFFFH
Image
CPU address space
Image
Image
Image
Image
FE000000H
FDFFFFFFH
02000000H
01FFFFFFH
01000000H
00FFFFFFH
00000000H
Physical address space
On-chip peripheral I/O
Internal RAM
(Access prohibited)
Internal ROM
xxFFFFFFH
xx000000H
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 ...