The PS supports processor events (Table: PL Event Signals) to and from the PL. These signals are asynchronous to the PS and PS provided PL clocks. Table 35-7: PL Event Signals Type Signal Description FPD events APU event input Causes CPU to wake from the wait for event (WFE) state. APU event output Asserted when one of the CPUs has executed a send event (SEV) instruction. LPD events RPU event input (2) Event input to the RPU (one event signal to each RPU). RPU event output (2) Event output from the RPU (one event signal from each RPU). Standby (FPD) APU WFE CPU standby mode. Asserted when CPU is waiting for an event. APU WFI CPU standby mode. Asserted when a CPU is waiting for an interrupt. For further details, refer to Application Processing Unit and Real-time Processing Unit.