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W O R K I N G W I T H T H E C P U
Fault checking sequence
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123
The conditions that generate each of the faults are discussed in the following
sections.
Alignment faults
If alignment fault checking is enabled (the A bit in the R1: Control register is set;
see "R1: Control register," beginning on page 88), the MMU generates an alignment
fault on any data word access if the address is not word-aligned, or on any halfword
access if the address is not halfword-aligned — irrespective of whether the MMU is
enabled. An alignment fault is not generated on any instruction fetch or byte
access.
Modified virtual address
Check address alignment
Get page
table entry
Get first-level descriptor
Section
Page
Check domain status
Section
Page
Client (01)
Client (01)
Check
access
permissions
Check
access
permissions
Physical address
Manager
(11)
Misaligned
Alignment
fault
Violation
Page
translation
fault
Page
domain
fault
Page
permission
fault
Invalid
No access (00)
Reserved (10)
Invalid
No access (00)
Reserved (10)
Section
domain
fault
Section
permission
fault
Violation
Section
translation
fault
Summary of Contents for NS9215
Page 1: ...NS9215 Hardware Reference 90000847_C Release date 10 April 2008...
Page 3: ......
Page 4: ......
Page 26: ...26 Hardware Reference NS9215...
Page 44: ...P I N O U T 26 5 System clock 44 Hardware Reference NS9215 System clock drawing...
Page 52: ...P I N O U T 26 5 Power and ground 52 Hardware Reference NS9215...
Page 80: ...I O C O N T ROL M O D U L E Memory Bus Configuration register 80 Hardware Reference NS9215...
Page 136: ...WOR KI N G W I TH T H E C P U Noncachable instruction fetches 136 Hardware Reference NS9215...
Page 202: ...S Y S T E M C O N T RO L M OD U L E RTC Module Control register 202 Hardware Reference NS9215...
Page 354: ...E X T E R N A L D M A DMA Peripheral Chip Select register 354 Hardware Reference NS9215...
Page 472: ...R E A L TI M E C L O C K M O D U L E General Status register 472 Hardware Reference NS9215...
Page 512: ...TI M I NG Clock timing 512 Hardware Reference NS9215...
Page 515: ...PA CKA GING Processor Dimensions www digiembedded com 515...
Page 516: ...PA CKA GING Processor Dimensions 516 Hardware Reference NS9215...