Figure 7-2 Translating Page Tables - Epson ARM720T Core Cpu Manual

The translation table has up to 4096 x 32-bit entries, each describing 1MB of virtual memory.
This enables up to 4GB of virtual memory to be addressed. Figure 7-2 shows the table walk
process.
Level one fetch
Translation
TTB base
Indexed by
modified
virtual
address
bits [31:20]
4096 entries
ARM720T CORE CPU MANUAL
Level two fetch
table
Invalid
00
Section base
10
Indexed by
modified
01
virtual
address
11
bits [19:0]
Coarse page
table base
Indexed by
modified
virtual
address
bits [19:12]
Fine page
table base
Indexed by
modified
virtual
address
bits [19:10]

Figure 7-2 Translating page tables

EPSON
Large page base
Indexed by
modified
virtual
Coarse page table
address
bits [15:0]
Invalid
00
01
Small page base
10
Indexed by
Invalid
modified
11
virtual
address
bits [11:0]
256 entries
Fine page table
Invalid
00
01
10
Tiny page base
11
Indexed by
modified
1024 entries
virtual
address
bits [9:0]
7: Memory Management Unit
Section
1 MB
Large page
16 KB subpage
16 KB subpage
16 KB subpage
16 KB subpage
64 KB
Small page
1 KB subpage
1 KB subpage
1 KB subpage
1 KB subpage
4 KB
Tiny page
1 KB
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