SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
As Table 1-19 shows, all exceptions have an associated priority, with a lower priority value indicating a higher priority and configurable priorities for all exceptions except Reset, Hard fault, and NMI. If software does not configure any priorities, then all exceptions with a configurable priority have a priority of 0. For information about configuring exception priorities, see Section 2.5.8 and Section 2.4.6.
NOTE
Configurable priority values for the MSP432E4 implementation are in the range 0 to 7. This means that the Reset, Hard Fault, and NMI exceptions (with fixed negative priority values) always have higher priority than any other exception.
For example, assigning a higher priority value to IRQ[0] and a lower priority value to IRQ[1] means that IRQ[1] has higher priority than IRQ[0]. If both IRQ[1] and IRQ[0] are asserted, IRQ[1] is processed before IRQ[0].
If multiple pending exceptions have the same priority, the pending exception with the lowest exception number takes precedence. For example, if both IRQ[0] and IRQ[1] are pending and have the same priority, then IRQ[0] is processed before IRQ[1].
When the processor is executing an exception handler, the exception handler is preempted if a higher priority exception occurs. If an exception occurs with the same priority as the exception being handled, the handler is not preempted, regardless of the exception number. However, the status of the new interrupt changes to pending.