Atmel ARM-Based Evaluation Kit AT91SAM9N12-EK AT91SAM9N12-EK Ficha De Dados

ARM DDI0198D

2-19

The FSR accessed is determined by the value of the Opcode_2 field:

Data Fault Status Register (DFSR).

Instruction Fault Status Register (IFSR).

The fault type encoding is listed in Table 3-9 on page 3-22.

You can access the FSRs using the following instructions:

MRC p15, 0, <Rd>, c5, c0, 0 ;read DFSR
MCR p15, 0, <Rd>, c5, c0, 0 ;write DFSR
MRC p15, 0, <Rd>, c5, c0, 1 ;read IFSR
MCR p15, 0, <Rd>, c5, c0, 1 ;write IFSR

The format of the Fault Status Register is shown in Figure 2-8.

Table 2-15 shows the bit field descriptions for the FSR. 

UNP/SBZ

31

9 8 7

4 3

0

0

Domain

Status

[31:9] UNP/SBZP.

[8] 

Always reads as zero. Writes ignored.

[7:4] 

Specifies which of the 16 domains (D15-D0) was being 
accessed when a data fault occurred.

[3:0]

Type of fault generated (see Table 2-16 on page 2-20).