Datasheet

2.2.7 RTC

The RTC is an always powered-on block that remains active in all low power modes.

The time counter within the RTC is clocked by a 32.768 kHz clock sourced from an

external crystal using the oscillator or clock directly from RTC_CLKIN pin.

RTC is reset on power-on reset, and a software reset bit in RTC can also initialize all

RTC registers. During chip power-down, RTC is powered from the backup power

supply (VBAT), electrically isolated from the rest of the chip, continues to increment

the time counter (if enabled) and retain the state of the RTC registers. The RTC

registers are not accessible.

The RTC module has the following features

• 32-bit seconds counter with roll-over protection and 32-bit alarm

• 16-bit prescaler with compensation that can correct errors between 0.12 ppm and

3906 ppm

• Register write protection with register lock mechanism

• 1 Hz square wave or second pulse output with optional interrupt

• 64-bit monotonic counter with roll-over protection

2.2.8

PIT

The Periodic Interrupt Timer (PIT) is used to generate periodic interrupt to the CPU. It

has four independent channels and each channel has a 32-bit counter. Two channels

can be chained together to form a 64-bit counter.

The PIT module can trigger a DMA transfer on the first four DMA channels. and also

can be selected as ADC, TPM, and DAC trigger source.

The PIT module has the following features:

• Each 32-bit timers is able to generate DMA trigger

• Each 32-bit timers is able to generate timeout interrupts

• Two timers can be cascaded to form a 64-bit timer

• Each timer can be programmed as ADC/TPM trigger source

• Timer 0 is able to trigger DAC

Overview

Kinetis KL82 Microcontroller, Rev. 3, 08/2016

NXP Semiconductors