SAM3A8C Atmel Corporation, SAM3A8C Datasheet - Page 189

• Manufacturer Part Number: SAM3A8C
• Manufacturer: Atmel Corporation

11.21.15 System control block design hints and tips
11057A–ATARM–17-Feb-12
11057A–ATARM–17-Feb-12
Ensure software uses aligned accesses of the correct size to access the system control block
registers:
The processor does not support unaligned accesses to system control block registers.
In a fault handler. to determine the true faulting address:
Software must follow this sequence because another higher priority exception might change the
MMFAR or BFAR value. For example, if a higher priority handler preempts the current fault han-
dler, the other fault might change the MMFAR or BFAR value.
• except for the CFSR and SHPR1-SHPR3, it must use aligned word accesses
• for the CFSR and SHPR1-SHPR3 it can use byte or aligned halfword or word accesses.
• Read and save the MMFAR or BFAR value.
• Read the MMARVALID bit in the MMFSR, or the BFARVALID bit in the BFSR. The MMFAR or
BFAR address is valid only if this bit is 1.
SAM3X/A
SAM3X/A
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