Data Sheet

681
Atmel | SMART SAM D21 [DATASHEET]
Atmel-42181G–SAM-D21_Datasheet–09/2015
30.6.4 DMA, Interrupts and Events
Notes: 1. DMA request set on overflow, underflow or retrigger conditions.
2. Can perform capture or generate recoverable fault on an event input.
3. Can retrigger counter / control counter direction / stop the counter / decrement the counter / perform period
and pulse width capture / generate non-recoverable fault on an event input.
4. Can retrigger counter / increment or decrement counter depending on direction / start the counter / incre-
ment or decrement counter based on direction / increment counter regardless of direction / generate non-
recoverable fault on an event input.
30.6.4.1 DMA Operation
The TCC generates the following DMA requests:
z Overflow (OVF): the request is set when an update condition (overflow, underflow or re-trigger) is detected.
z Compare Match or Capture (MCx): for a compare channel, the request is set on each compare match detection.
For a capture channel, the request is set when valid data is present in CCx register, and cleared when CCx
register is read.
30.6.4.2 Interrupts
The TCC has the following interrupt sources:
z Overflow/Underflow: OVF. This is an asynchronous interrupt and can be used to wake-up the device from any
sleep mode.
z Retrigger: TRG. This is an asynchronous interrupt and can be used to wake-up the device from any sleep mode.
Table 30-4. Module request for TCC
Condition
Interrupt
request
Event
output
Event input DMA request DMA request is cleared
Overflow / Underflow X X X
(1)
Cleared when PER/PERB,
CCx/CCBx, PATT/PATTB
or WAVE/WAVEB register is
written.
Channel Compare Match
or Capture
X X X
(2)
X
For compare channel:
Cleared when CCBx register
is written.
For capture channel:
Cleared when CCx register
is read.
Retrigger X X
Count X X
Capture Overflow Error X
Synchronization Ready X
Debug Fault State X
Recoverable Faults X
Non-Recoverable Faults X
TCCx Event 0 input X
(3)
TCCx Event 1 input X
(4)