Real-time clock alarm

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A real time clock alarm is a feature that can be used to allow a computer to 'wake up' after shut down to execute tasks every day or on a certain day. It can sometimes be found in the 'Power Management' section of a motherboard's BIOS/UEFI setup. Wake On LAN, Wake on ring, and IPMI functions could also be used to start a computer after it is turned off.

In Linux, the real time clock alarm can be set or retrieved using /proc/acpi/alarm or /sys/class/rtc/rtc0/wakealarm. [1] Alternatively the rtcwake utility may be used which prevents problems when using local time instead of UTC by automatically processing the /etc/adjtime file. systemd can be used to wake a system and run a task at a specific time. [2]

In Microsoft Windows there are different programs which could be used to 'wake up' a computer from standby or hibernation. Task Scheduler settings for power management can be used to 'Wake the computer to run this task'.

Related Research Articles

<span class="mw-page-title-main">BIOS</span> Firmware for hardware initialization and OS runtime services

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<span class="mw-page-title-main">Real-time clock</span> Circuit in a computer that maintains accurate time

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<span class="mw-page-title-main">Alarm clock</span> Type of clock

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<span class="mw-page-title-main">ACPI</span> Computer firmware interface standard

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<span class="mw-page-title-main">Windows Clock</span> Time management in Microsoft Windows

Windows Clock is a time management app for Microsoft Windows, with five key features: alarms, world clocks, timers, a stopwatch, and focus sessions. The features are listed on a sidebar. The app is similar in functionality and design to the Clock app on iOS. Windows Clock was available on mobile devices for over a decade before it was available on PCs with the introduction of Windows 8.1. Tiles for alarms, timers, and the stopwatch can be pinned to the Start menu. The latest version of the app uses the Universal Windows Platform APIs and adopts Windows UI theme. Windows Clock is distinct from the Windows taskbar's clock, which has been part of Windows since 1995.

References

  1. "ACPI Wakeup - MythTV Official Wiki".
  2. "systemd.timer". freedesktop.org. Retrieved 27 October 2014.

See also