33.16.2 System Asynchronous Partial Wake-Up

When the system is in ULP1 mode, all clocks of the system (except SLCK and TD_SLCK) are stopped. When an asynchronous clock request from a peripheral occurs, the PMC partially wakes up the system to feed the clock only to this peripheral. The rest of the system is not fed with the clock, thus optimizing power consumption. Finally, depending on user-configurable conditions, the peripheral either wakes up the whole system if these conditions are met or stops the peripheral clock until the next clock request. If a wake-up request occurs, the Asynchronous Partial Wake-up mode is automatically disabled until the user instructs the PMC to enable asynchronous partial wake-up. This is done by setting PIDx in the PMC Asynchronous Partial Wake-Up Enable register (PMC_SLPWK_ER).