## ARM Fault Status Register Values (FSR register)

The lowest 4-bits of the FSR register indicates the fault generated by the MMU. The FSR register value is displayed as a result of entering an f command in the debug monitor.

Value | Explanation
0 | Vector exception
1 | Alignment fault
2 | Terminal exception
3 | Alignment fault
4 | External abort on linefetch for section translation
5 | Section translation fault (unmapped virtual address)
6 | External abort on linefetch for page translation
7 | Page translation fault (unmapped virtual address)
8 | External abort on non-linefetch for section translation
9 | Domain fault on section translation (i.e. accessing invalid domain)
A | External abort on non-linefetch for page translation
B | Domain fault on page translation (i.e. accessing invalid domain)
C | External abort on first level translation
D | Permission fault on section (i.e. no permission to access virtual address)
E | External abort on second level translation
F | Permission fault on page (i.e. no permission to access virtual address)

##### Related references

- ARM Exception Types
- ARM Fault Status Register Values
- ARM Processor Modes