CHAPTER 4 MEMORY MANAGEMENT SYSTEM
User’s Manual U14272EJ3V0UM
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4.2 Physical Address Space
Using a 32-bit address, the processor physical address space encompasses 4 GB. The V
R
4181 uses this 4 GB
physical address space as shown in Figure 4-1.
Figure 4-1. V
R
4181 Physical Address Space
0xFFFF FFFF
(Mirror image of 0x0000 0000 to 0x1FFF FFFF area)
ROM space (including a boot ROM)
External system bus memory space (ISA memory)
Internal ISA I/O space 1
Internal ISA I/O space 2
RFU
DRAM space
MBA bus I/O space
RFU
0x1800 0000
0x17FF FFFF
0x0C00 0000
0x0BFF FFFF
0x0B00 0000
0x0AFF FFFF
0x0D00 0000
0x0CFF FFFF
0x0A00 0000
0x09FF FFFF
0x0400 0000
0x03FF FFFF
0x0000 0000
0x1000 0000
0x0FFF FFFF
0x2000 0000
0x1FFF FFFF
External system bus I/O space (ISA I/O)
0x1400 0000
0x13FF FFFF