NRF9160-SICA-R7 datasheet(186/400 Pages) NORDIC

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Peripherals

6.11.5 Tick event

The TICK event enables low-power tickless RTOS implementation, as it optionally provides a regular

interrupt source for an RTOS with no need for use of the ARM SysTick feature.

Using the TICK event, rather than the SysTick, allows the CPU to be powered down while keeping RTOS

scheduling active.

Note: The TICK event is disabled by default.

6.11.6 Event control

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

PCLK16M and HFCLK from being requested when those events are triggered. This is managed using the

EVTEN register.

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

system described in Peripheral interface on page 15. The RTC task and event system is illustrated in the

following figure.

RTC core

TASK

Task signal from PPI

task

event

EVENT m

IRQ signal to NVIC

INTEN

RTC

EVTEN

Event signal to PPI

write

Figure 54: Tasks, events, and interrupts in the RTC

6.11.7 Compare

The RTC implements one COMPARE event for every available compare register.

When the COUNTER is incremented and then becomes equal to the value specified in the register CC[n],

the corresponding compare event COMPARE[n] is generated.

When writing a CC[n] register, the RTC COMPARE event exhibits several behaviors. See the following

figures for more information.

If a CC value is

0 when a CLEAR task is set, this will not trigger a COMPARE event.

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NRF9160-SICA-R7 Datasheet(PDF) 186 Page - Nordic Semiconductor