33.16.3 Asynchronous Partial Wake-Up of a Peripheral in Active Mode

When the system is in Active mode, peripherals enabled for asynchronous partial wake-up have their respective clocks stopped until the peripherals request a clock. When a peripheral requests the clock, the PMC provides the clock without CPU 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 Wake-up mode of the peripheral and provides the clock to the peripheral until the user instructs the PMC to re-enable partial wake-up on the peripheral. This is done by setting PIDx in PMC_SLPWK_ER.

If the conditions are not met, the peripheral clears the clock request and PMC stops the peripheral clock until the clock request is re-asserted by the peripheral.

Note: When asynchronous partial wake-up of a peripheral is enabled and the core is running (system not in ULP1 mode), the peripheral must not be accessed before a wake-up of the peripheral is performed.

Figure 33-10. Asynchronous Partial Wake-Up During Active Mode