NRF52810-QCAA-R datasheet(323/483 Pages) NORDIC

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Peripherals

SysClk

LFClk

PRESC

<<PRESC>>

0x001

0x000

0x001

TICK

COUNTER

0x000001

0x000

0x000000

Figure 77: Timing diagram - COUNTER_PRESCALER_1

6.16.4 Overflow features

The TRIGOVRFLW task sets the COUNTER value to 0xFFFFF0 to allow SW test of the overflow condition.

OVRFLW occurs when COUNTER overflows from 0xFFFFFF to 0.

Important: The OVRFLW event is disabled by default.

6.16.5 TICK event

The TICK event enables low power "tick-less" RTOS implementation as it optionally provides a regular

interrupt source for a RTOS without the need to use the ARM® SysTick feature.

Using the RTC TICK event rather than the SysTick allows the CPU to be powered down while still keeping

RTOS scheduling active.

Important: The TICK event is disabled by default.

6.16.6 Event control feature

To optimize RTC power consumption, events in the RTC can be individually disabled to prevent PCLK16M

and HFCLK being requested when those events are triggered. This is managed using the EVTEN register.

For example, if the TICK event is not required for an application, this event should be disabled as it is

frequently occurring and may increase power consumption if HFCLK otherwise could be powered down for

long durations.

This means that the RTC implements a slightly different task and event system compared to the standard

system described in Peripheral interface on page 94. The RTC task and event system is illustrated in

Tasks, events and interrupts in the RTC on page 324.

4430_161 v1.0

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NRF52810-QCAA-R Datasheet(PDF) 323 Page - Nordic Semiconductor