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99
Working with the CPU
Fault checking sequence

The sequence the MMU uses to check for access faults is different for sections and

pages. Figure 36 shows the sequence for both types of access.

0 0 1 0 Read only Read only
0 0 0 1 Read only Read only
0 0 1 1 UNPREDICTABLE UNPREDICTABLE
0 1 x x Read/write No access
1 0 x x Read/write Read only
1 1 x x Read/write Read/write
AP S R Privileged permissions User permissions

Table 42: Interpreting access permission (AP) bits