Image (Virtual Address Space) - NEC V854 UPD703006 User Manual

32/16-bit single-chip microcontroller hardware

Table of Contents

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 3-5 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,

010000000H, 02000000H... through FF000000H.

CPU address space

CHAPTER 3 CPU FUNCTIONS

Figure 3-5. Image on Address Space

User's Manual U11969EJ3V0UM00

Physical address space

Peripheral I/O

Internal RAM

External memory

Internal ROM