Raspberry Pi Stack Exchange
Raspberry Pi Stack Exchange

Questions tagged [system-clock]

The system clock is part of the operating system that keeps time. The Raspberry Pi does not have a hardware clock, so for correctness the time is usually kept synced with a network source. It is also possible to add a clock device.

In order to keep the cost of the Raspberry Pi down, a system clock was not included, though through the use of external devices, it may be possible to keep time on the device.

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How can I keep system time?

I know that Raspberry Pi does not come with a system clock to save money. How can I keep system time though?
user46
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How accurate is Raspberry Pi's timekeeping?

I realize that since Raspberry Pi doesn't have a hardware real-time clock built in, some issues with accurate timekeeping may present themselves, even when persistence across reboots is not a requirement. This can largely be mitigated by running a…
user13
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Will RPi suffer from the Y2K38 bug?

Just out of curiosity, what will happen to RPis Model A and B on January 19, 2038 in 3:14:07 AM GMT? Are they affected by the Y2K38 bug?
DaGhostman Dimitrov
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How to change the clock to 12-hour format in Raspbian?

By default, Raspbian displays a 24-hour clock: Normally, LXDE provides an option to change the clock format by opening Panel Preferences, selecting "Digital Clock", and clicking Preferences. However, this is disabled: How do I change the format?
Nathan Osman
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After reboot, my RPi is one hour off -- How to adjust for Daylight Savings problems?

The electricity to my apartment went out a few days ago. I use my RPi to record data and store it in a database. I've just learned that the time for all my data has been off by an hour because the RPi's clock is off by an hour. From here I issued tz…
Matthew Moisen
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Do I need an RTC if my Raspberry Pi is continuously connected to the Internet?

How accurate would the time on my Raspberry Pi 3 be if it is continuously connected to the Internet, but without an RTC?
ON5MF Jurgen
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Keeping System Time Without Network

Is there a way to sync the clock with the internet (as easily done) upon one startup, then shutdown, move the computer to another place WITHOUT an internet connection, and get a reasonable time? I'm not looking for "This is the real time as of right…
Aviator45003
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System time coming through SSH?

I have a setup where my Pi is connected to power and to my router, and I then set up a connection with my laptop through SSH (a good setup for saving space, if you don't have a lot). I fired up my Pi just now and noticed I could access the time, and…
ACarter
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Raspberry pi cannot synchronize clock

I have bought three raspberry pi's with the intention of using them as temperature sensors throughout the building. I have bought the following models: 1 raspberry pi 4 model b 2gb 2 raspberry pi 4 model b 4gb (due to chip shortage 2gb were no…
treskilion
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How to get the exact clock speed at the raspberry pi is running?

As per the specification. If you power the raspberry pi from the USB port from PC,It will run at half speed of what it can achieve. But when you power it from the external source then it runs at full speed of 700 MHz. So I want to ask how can we see…
Jimit
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Cycles per instruction

I have a default raspberry pi running raspbian, assuming it’s running at 700MHz. I’d think that every instruction would take only one or a few cycles at most. In my experiments that doesn’t seem to be the case. I use the 1MHz timer and count the…
rumpel
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systemd-timesyncd always restarted once got Router Advertisement

On raspberry pi os, pi zeor 2 w, the systemd-timesyncd always restat once received Router Advertisement from router The messages are like following: Nov 28 12:22:46 raspberrypi dhcpcd[837]: wlan0: Router Advertisement from…
ygofoust
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set system clock to value received from GPS

I've got a USB GPS receiver permanently attached to my raspberry pi. At boot time, I would like raspbian to wait until the GPS has a signal, then set the OS's time to whatever the GPS says. I've already installed gpsd and gpspipe and I'm logging the…
Fidel
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Windows 10 IoT does not automatically use the Real Time Clock module to automatically update the system time

bought a brand new Raspberry Pi 3 DS3231 RTC Module and integrated to correct gpio pins as it should be. But somehow Windows 10 IOT seems not detect this module. than attempted to follow follow instructions. but what! all instructions are for linux.…
Fables Alive
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Set manually datetime raspberry

I have a project that uses Raspberry in offline mode. We know it doesn't have a clock when it powers off. The router, even in offline mode, have a clock when it power off. So, i have 2 questions: 1 - It's possible configure raspberry to get a hour…
FelipeFonsecabh
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