Digi NS9215 User Manual
Page 117

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W O R K I N G W I T H T H E C P U
MemoryManagement Unit (MMU)
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117
Translating
sequence for small
page references
If a small page descriptor is included in a fine page table, the upper two bits of the
page index and low-order two bits of the fine page table index overlap. Each fine
page table entry for a small page must be duplicated four times.
31
14 13
0
Translation base
1
Translation table base
31
14 13
0
Translation base
2
Table index
0 0
31
2019
0
Table index
Page index
First-level descriptor
31
0
Coarse page table base address
2
0 1
1
3
4
5
Domain 1
31
0
Coarse page table base address
Level two
table index
12 11
Modified virtual address
8
9
10
1
2
9
10
31
121110 9 8 7 6 5 4 3 2 1 0
0
0
L2 table index
0
1
B
C
AP0
AP1
AP2
AP3
Page base address
Page base address
31
0
1211
Page index
Physical address
Second-level descriptor