Epson ARM720T Manuel D’Utilisation

Coarse page table descriptor bit assignments are described in Table 7-5.

A fine page table descriptor provides the base address of a page table that contains level two 

descriptors for large page, small page, or tiny page accesses. Fine page tables have 1024 

entries, splitting the 1MB that the table describes into 1KB blocks. Figure 7-7 shows the 

format of a fine page table descriptor.

Figure 7-7  Fine page table descriptor

 

If a fine page table descriptor is returned from the level one fetch, a level two fetch 

is initiated.

Fine page table descriptor bit assignments are described in Table 7-6.

Table 7-5  Coarse page table descriptor bits

31:10

These bits form the base for referencing the level two 
descriptor (the coarse page table index for the entry is 
derived from the MVA)

9

Always written as 0

8:5

These bits specify one of the 16 possible domains 
(held in the Domain Access Control Registers) that 
contain the primary access controls

4

Always written as 1

3:2

Always written as 0

1:0

These bits must be 01 to indicate a coarse page table 
descriptor

Table 7-6  Fine page table descriptor bits

31:12

These bits form the base for referencing the level two 
descriptor (the fine page table index for the entry is 
derived from the MVA)

11:9

Always written as 0

8:5

These bits specify one of the 16 possible domains 
(held in the Domain Access Control Registers) that 
contain the primary access controls

4

Always written as 1

3:2

Always written as 0

1:0

These bits must be b11 to indicate a fine page table 
descriptor

31

12 11

9 8

5 4 3 2 1 0

Fine page table base address

Domain

1

1 1

SBZ

SBZ