ARM Cortex-M3 User Manual

Nested Vectored Interrupt Controller
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Configurable Fault Status Registers
Use the three Configurable Fault Status Registers to obtain information about local
faults. These registers include:
• Memory Manage Fault Status Register
• Bus Fault Status Register on page 8-34
• Usage Fault Status Register on page 8-35.
The flags in these registers indicate the causes of local faults. Multiple flags can be set
if more than one fault occurs. These register are read/write-clear. This means that they
can be read normally, but writing a 1 to any bit clears that bit.
The register addresses, access types, and Reset states are:
Address
0xE000ED28 Memory Manage Fault Status Register
0xE000ED29 Bus Fault Status Register
0xE000ED2A Usage Fault Status Register
Access Read/write-one-to-clear
Reset state
0x00000000
Figure 8-16 shows the bit assignments of the Configurable Fault Status Registers.
Figure 8-16 Configurable Fault Status Registers bit assignments
Note
Accesses to each individual status register must be aligned to the appropriate address
and size. Either the whole 32-bit word is accessed using address
0xE000ED28 or the BFSR
and MFSR are accessed as a byte size each correctly aligned or the UFSR is accessed
as a half-word correctly aligned to address
0xE000ED2A .
Memory Manage Fault Status Register
The flags in the Memory Manage Fault Status Register indicate the cause of memory
access faults.
The register address, access type, and Reset state are:
Address
0xE000ED28
Access Read/write-one-to-clear
Reset state
0x00000000
31 16 15 8 7 0
Bus Fault Status
Register
Usage Fault Status
Register
Memory Manage
Fault Status Register

ARM Cortex-M3 Specifications

General

Architecture	ARMv7-M
Instruction Set	Thumb-2
Pipeline Stages	3-stage
Interrupts	Nested Vectored Interrupt Controller (NVIC)
Interrupt Controller	Nested Vectored Interrupt Controller (NVIC)
Memory Protection Unit	Optional
Power Consumption	Varies by implementation
Max Clock Speed	Up to 100 MHz
Debugging	JTAG and Serial Wire Debug (SWD)
Operating Voltage	1.8V to 3.6V
Manufacturing Process	Varies by implementation
Core Type	32-bit