54.6.13 External Event/Trigger Conditions
An external event can be programmed to be detected on one of the clock sources (XC0, XC1, XC2) or TIOBx. The external event selected can then be used as a trigger.
The event trigger is selected using TC_CMR.EEVT. The trigger edge (rising, falling or both) for each of the possible external triggers is defined in TC_CMR.EEVTEDG. If EEVTEDG is cleared (none), no external event is defined.
If TIOBx is defined as an external event signal (EEVT = 0), TIOBx is no longer used as an output and the compare register B is not used to generate waveforms and subsequently no IRQs. In this case, the TC channel can only generate a waveform on TIOAx.
When an external event is defined, it can be used as a trigger by setting TC_CMR.ENETRG.
As in Capture mode, the SYNC signal and the software trigger are also available as triggers. RC Compare can also be used as a trigger depending on the parameter WAVSEL.