21.3.4 Events

The TCA is an event generator. The following events will generate a one-cycle strobe on the event channel outputs:
  • Timer overflow
  • Timer underflow in Split mode
  • Compare match channel 0
  • Compare match channel 1
  • Compare match channel 2

The peripheral can take the following actions on an input event:

  • The counter counts positive edges of the event signal.
  • The counter counts both positive and negative edges of the event signal.
  • The counter counts prescaled clock cycles as long as the event signal is high.
  • The counter counts prescaled clock cycles. The event signal controls the direction of counting. Up-counting when the event signal is low and down-counting when the event signal is high.

The specific action is selected by writing to the Event Action bits (EVACT) in the Event Control register (TCAn.EVCTRL). Events as input are enabled by writing a '1' to the Enable Count on Event Input bit (CNTEI in TCAn.EVCTRL).

Event-controlled inputs are not used in Split mode.