Raspberry Pi Stack Exchange
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Questions tagged [rtc]

a Real time Clock, a computer clock.

A real-time clock (RTC) is a computer clock (most often in the form of an integrated circuit) that keeps track of the current time. Although the term often refers to the devices in personal computers, servers and embedded systems, RTCs are present in almost any electronic device which needs to keep accurate time.

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How to install Real Time Clock (RTC) on Raspbian?

I have: Raspberry Pi with 2015-05-05-raspbian-wheezy ds1307 attached (it's an Adafruit board, pullup resistors not installed). How do I: configure drivers make sure the Pi actually uses the RTC time on startup? I've actually done the first…
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How does Pi keep track of time interval?

As I understand RTC is needed to keep track of time. However, Raspberry Pi does not have that and use NTP servers to synchronize its time. All that is fine, but how does Pi know that one millisecond or one second has elapsed. How is Pi aware of the…
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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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How to setup a MCP79410 real time clock?

I was trying to set up a MCP79410 real time clock (RTC) and had to search quite a bit until I found a way to integrate the RTC's time signal into my Raspbian Jessie: Apparently, even there, some things changed over the last updates of Raspbian and…
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Would it be possible to use the DS1302 made for Arduino?

I got some spare DS1302 chips that I'd like to connect to my Raspberry Pi to use as a RTC, but I'm not so sure how to. How would I go about it?
Ivan
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How can I automatically update the hwclock with NTP when I have internet connection

I'm using an RPi with Raspbian which runs the NTP-daemon by default. I have connected an rtc-ds1307 external i2c hardware clock. I was following the instructions given here to set it…
Thomas
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Why many RaspberryPi add on has pull up resistors?

I was looking at the I2C in RaspberryPi and I saw that they are pulled by 1.8K resistors(I am not talking about the ID pins). On the other hand, I got one of those RTC and they got two 222Ohm pull up resistor on board. My questions are: First, why…
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Raspberry Pi stable date time

I'm working on a Raspberry Pi project, in which date and time are the most important factors. So, I want them to be very accurate. I know there are two methods to configure the Raspberry Pi's date and time, which are using an RTC module or auto…
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How to display real time on a Pi

How do I give my Pi system a Real Time Clock (RTC)? Is this possible? As each time when I power off my Pi, and the next time when it boots, it displays the previous power off time. Can someone explain me how to initalise or setup a RTC in my Pi?
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Using RTC on Raspberry Pi Zero while SDA/SCL pins are occupied

I have a portable project on my Raspberry Pi Zero and I am using a i2c 0.96" OLED on the SDA/SCL pins on my Raspberry Pi. I would like to add a RTC Module to my project, but all of the tutorials I have seen involve using the SDA/SCL pins for…
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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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DS3231 RTC not keeping time after shutdown on Raspberry Pi?

I'm assembling a Smart Mirror for an applied project for college. This mirror has a Raspberry Pi 3 on the back. How this all started is that the campus' network blocks NTP, so we had to buy an RTC chip for the Pi to be able to keep track of time…
flemingmirror
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real time clock puzzle with new rasbian jessie

I have been trying to install a RTC on my raspberry pi 2 (running Raspbian Jessie lite 2015-11-21) and I run into the following problem that puzzles me: I set the correct time on the hardware clock and shut down the pi. I unplug the ethernet…
Clémentine
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Using I2C in C++ on Raspberry Pi

I have a Raspberry Pi model B with Raspbian and a Busware SD0 cape. The SD0 has an RTC that can be read via the I2C bus. I want set the time and date of the Raspberry Pi because it is not always connected to the internet so the time can't be set via…
Doan
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i2c Real Time Clock IC on Raspberry

I am using an industrial device based on a Compute Module Raspberry Pi 3 called Kunbus RevPi Core 3+. The device is shipped with Raspbian and a pre compiled Image but I would like to install an Ubuntu Server 22.04 distro (much better for my…
Stefano Bossi
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