
808
SAM4CP [DATASHEET]
43051E–ATPL–08/14
37.6.9 Trigger Conditions
In addition to the SYNC signal, the software trigger and the RC compare trigger, an external trigger can be defined.
The ABETRG bit in the TC_CMR selects TIOA or TIOB input signal as an external trigger. The External Trigger Edge
Selection parameter (ETRGEDG field in TC_CMR) defines the edge (rising, falling or both) detected to generate an
external trigger. If ETRGEDG = 0 (none), the external trigger is disabled.
37.6.10 Waveform Operating Mode
Waveform operating mode is entered by setting the WAVE parameter in TC_CMR (Channel Mode Register).
In Waveform Operating Mode the TC channel generates 1 or 2 PWM signals with the same frequency and independently
programmable duty cycles, or generates different types of one-shot or repetitive pulses.
In this mode, TIOA is configured as an output and TIOB is defined as an output if it is not used as an external event
(EEVT parameter in TC_CMR).
Figure 37-6
shows the configuration of the TC channel when programmed in Waveform Operating Mode.
37.6.11 Waveform Selection
Depending on the WAVSEL parameter in TC_CMR (Channel Mode Register), the behavior of TC_CV varies.
With any selection, TC_RA, TC_RB and TC_RC can all be used as compare registers.
RA Compare is used to control the TIOA output, RB Compare is used to control the TIOB output (if correctly configured)
and RC Compare is used to control TIOA and/or TIOB outputs.