30.6.4 Sleep Mode Operation
The EVSYS can generate interrupts to wake up the device from any sleep mode.
To be able to run in standby, the Run in Standby bit in the Channel register (CHANNELn.RUNSTDBY) must be set to ‘1’. When the Generic Clock On Demand bit in Channel register (CHANNELn.ONDEMAND) is set to ‘1’ and the event generator is detected, the event channel will request its clock (GCLK_EVSYS_CHANNEL_n). The event latency for a resynchronized channel path will increase by two GCLK_EVSYS_CHANNEL_n clock (i.e., up to five GCLK_EVSYS_CHANNEL_n clock cycles).
A channel will behave differently in different sleep modes regarding to CHANNELn.RUNSTDBY and CHANNELn.ONDEMAND, as shown in the table below:
| CHANNELn.PATH | CHANNELn.ONDEMAND | CHANNELn.RUNSTDBY | Sleep Behavior |
|---|---|---|---|
| ASYNC | 0 | 0 | Only run in Idle Sleep modes if an event must be propagated. Disabled in Standby Sleep mode. |
| SYNC/RESYNC | 0 | 0 | N/A. Works only in Active mode. |
| SYNC/RESYNC | 0 | 1 | Always run in Idle and Standby Sleep modes. |
| SYNC/RESYNC | 1 | 0 | Only run in Idle Sleep mode if an event must be propagated. Disabled in Standby Sleep mode. Two GCLK_EVSYS_n latency added in RESYNC path before the event is propagated internally. |
| SYNC/RESYNC | 1 | 1 | Always run in Idle and Standby Sleep modes. Two GCLK_EVSYS_n latency added in RESYNC path before the event is propagated internally. |
Note: The ONDEMAND and RUNSTDBY bits have no effect for channels when the asynchronous path is
selected.