Fault Status Registers And Fault Address Registers; Lockup; Power Management; Table 20. Fault Status And Fault Address Registers - ST STM32H7 Series Programming Manual

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2.4.3

Fault status registers and fault address registers

The fault status registers indicate the cause of a fault. For bus faults and memory
management faults, the fault address register indicates the address accessed by the
operation that caused the fault, as shown in
Handler
Hard fault
Memory
management fault
Bus fault
Usage fault
2.4.4

Lockup

The processor enters a lockup state if a hard fault occurs when executing the NMI or hard
fault handlers. When the processor is in lockup state it does not execute any instructions.
The processor remains in lockup state until either:
•
It is reset
•
An NMI occurs
•
It is halted by a debugger
If lockup state occurs from the NMI handler a subsequent NMI does not cause the
processor to leave lockup state.
2.5

Power management

The STM32 and Cortex-M4 processor sleep modes reduce power consumption:
•
Sleep mode stops the processor clock. All other system and peripheral clocks may still
be running.
• Deep sleep mode stops most of the STM32 system and peripheral clocks. At product
level, this corresponds to either the Stop or the Standby mode. For more details, please
refer to the "Power modes" Section in the STM32 reference manual.
The SLEEPDEEP bit of the SCR selects which sleep mode is used, as described in
control register (SCR) on page
modes see the STM32 product reference manual.
This section describes the mechanisms for entering sleep mode, and the conditions for
waking up from sleep mode.

Table 20. Fault status and fault address registers

Status register Address register
name name
HFSR -
MMFSR MMFAR
BFSR BFAR
UFSR -
Table 20.
Register description
Hard fault status register (HFSR) on page 241
Memory management fault address register
(MMFAR) on page 242
Bus fault address register (BFAR) on page 242
Configurable fault status register (CFSR;
UFSR+BFSR+MMFSR) on page 237
230. For more information about the behavior of the sleep
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