23.4.1 Initialization

To operate the PIT, follow these steps:
  1. Configure the RTC clock CLK_RTC as described in 23.3.1.1 Configure the Clock CLK_RTC.
  2. Enable the interrupt by writing a '1' to the Periodic Interrupt bit (PI) in the PIT Interrupt Control register (RTC.PITINTCTRL).
  3. Select the period for the interrupt and enable the PIT by writing the desired value to the PERIOD bit field and a '1' to the PIT Enable bit (PITEN) in the PIT Control A register (RTC.PITCTRLA).
Note: The RTC peripheral is used internally during device start-up. Always check the Busy bits in the RTC.STATUS and RTC.PITSTATUS registers, also on initial configuration.