To start using the timer/counter in a basic mode, follow these steps:
Write a TOP value to the Period
register (TCAn.PER)
Enable the peripheral by writing a
'1' to the ENABLE bit in the Control A register (TCAn.CTRLA).
The
counter will start counting clock ticks according to the prescaler setting in the
Clock Select bit field (CLKSEL) in TCAn.CTRLA.
Optional: By writing a '1' to the
Enable Count on Event Input bit (CNTEI) in the Event Control register (TCAn.EVCTRL),
event inputs are counted instead of clock ticks.
The counter value can be read from
the Counter bit field (CNT) in the Counter register (TCAn.CNT).