2.5.5.2.2 Wakeup from WFE

The processor wakes up if:

• It detects an exception with sufficient priority to cause exception entry
• It detects an external event signal, see 2.5.5.4 External Event Input
• In a multiprocessor system, another processor in the system executes an SEV instruction

In addition, if the SEVONPEND bit in the SCR is set to 1, any new pending interrupt triggers an event and wakes up the processor, even if the interrupt is disabled or has insufficient priority to cause exception entry. For more information about the SCR, see 2.7.2.6 System Control Register.