SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
All fault exceptions except for hard fault have configurable exception priority (see SYSPRI1 in Section 2.5.8). Software can disable execution of the handlers for these faults (see SYSHNDCTRL in Section 2.5.11).
Usually, the exception priority, together with the values of the exception mask registers, determines whether the processor enters the fault handler, and whether a fault handler can preempt another fault handler, as described in Section 1.6.
In some situations, a fault with configurable priority is treated as a hard fault. This process is called priority escalation, and the fault is described as escalated to hard fault. Escalation to hard fault occurs when:
If a bus fault occurs during a stack push when entering a bus fault handler, the bus fault does not escalate to a hard fault. Thus if a corrupted stack causes a fault, the fault handler executes even though the stack push for the handler failed. The fault handler operates but the stack contents are corrupted.
NOTE
Only Reset and NMI can preempt the fixed priority hard fault. A hard fault can preempt any exception other than Reset, NMI, or another hard fault.