30.6.4 Sleep Mode Operation
The Event System can generate interrupts to wake up the device from the Idle or Standby 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 the 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 increases by two GCLK_EVSYS_CHANNEL_n clock (in other words, up to five GCLK_EVSYS_CHANNEL_n clock cycles).
A channel will behave differently in different sleep modes depending on whether using CHANNELn.RUNSTDBY or CHANNELn.ONDEMAND:
| CHANNELn.PATH | CHANNELn. ONDEMAND | CHANNELn. RUNSTDBY | Sleep Behavior |
|---|---|---|---|
| ASYNC | 0 | 0 | Only run in Idle modes if an event must be propagated. Disabled in Standby Sleep mode. |
| SYNC/RESYNC | 0 | 1 | Run in both Idle and Standby Sleep modes. |
| SYNC/RESYNC | 1 | 0 | Only run in Idle modes 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 | Run in both Idle and Standby Sleep modes. Two GCLK_EVSYS_n latency added in RESYNC path before the event is propagated internally. |