When the system is in Active mode, peripherals enabled for asynchronous partial wakeup have their respective clocks stopped until the peripherals request a clock. When a peripheral requests the clock, the PMC provides the clock without processor intervention.
The triggering of the peripheral clock request depends on conditions which can be configured for each peripheral. If these conditions are met, the peripheral asserts a request to the PMC. The PMC disables the Asynchronous Partial Wakeup mode of the peripheral and provides the clock to the peripheral until the user instructs the PMC to re-enable partial wakeup on the peripheral. This is done by setting PMC_SLPWK_ER.PIDx.
If the conditions are not met, the peripheral clears the clock request and the PMC stops the peripheral clock until the clock request is reasserted by the peripheral.
