Datasheet

Figure 49-13. Changing the Period Using Buffering
COUNT
"reload" update
"write"
MAX
ZERO
New value written to
PERBUF that is higher
than current COUNT
New value written to
PERBUF that is lower
than current COUNT
PER is updated with
PERBUF value
49.6.2.7 Capture Operations
To enable and use capture operations, the Match or Capture Channel x Event Input Enable bit in the
Event Control register (EVCTRL.MCEIx) must be written to '1'. The capture channels to be used must
also be enabled in the Capture Channel x Enable bit in the Control A register (CTRLA.CPTENx) before
capturing can be performed.
Event Capture Action
The compare/capture channels can be used as input capture channels to capture events from the Event
System, and give them a timestamp. The following figure shows four capture events for one capture
channel. Event system channels must be configured to operate in asynchronous mode when used for
capture operations.
Figure 49-14. Input Capture Timing
events
COUNT
MAX
ZERO
Capture 0 Capture 1 Capture 2 Capture 3
For input capture, the Buffer register and the corresponding CCx act like a FIFO. When CCx is empty or
read, any content in CCBUFx is transferred to CCx. The Buffer Valid flag is passed to set the CCx
Interrupt flag (IF) and generate the optional interrupt, event, or DMA request. The CCBUFx register value
cannot be read, all captured data must be read from the CCx register.
SAM D5x/E5x Family Data Sheet
TCC – Timer/Counter for Control Applications
© 2019 Microchip Technology Inc.
Datasheet
DS60001507E-page 1815