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WORKING WITH THE CPU
Fault checking sequence
122 Hardware Reference NS9215
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Fault checking sequence
The sequence the MMU uses to check for access faults is different for sections and
pages. The next figure shows the sequence for both types of access.
AP S R Privileged permissions User permissions
0 0 0 0 No access No 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