Datasheet

 2017 Microchip Technology Inc. DS60001516A-page 547
SAM9G20
33.5.12 External Event/Trigger Conditions
An external event can be programmed to be detected on one of the clock sources (XC0, XC1, XC2) or TIOB. The external event selected
can then be used as a trigger.
The EEVT parameter in TC_CMR selects the external trigger. The EEVTEDG parameter defines the trigger edge for each of the possible
external triggers (rising, falling or both). If EEVTEDG is cleared (none), no external event is defined.
If TIOB is defined as an external event signal (EEVT = 0), TIOB 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 TIOA.
When an external event is defined, it can be used as a trigger by setting bit ENETRG in TC_CMR.
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.
33.5.13 Output Controller
The output controller defines the output level changes on TIOA and TIOB following an event. TIOB control is used only if TIOB is defined
as output (not as an external event).
The following events control TIOA and TIOB: software trigger, external event and RC compare. RA compare controls TIOA and RB com-
pare controls TIOB. Each of these events can be programmed to set, clear or toggle the output as defined in the corresponding parameter
in TC_CMR.