a Real time Clock, a computer clock.

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Where exactly are these GPIO pins located on Raspberry PI 2 Model B?

I am having hard time understanding the Raspberry PI 2 Model B's PINOUT. I have RTC Module I want to use with my PI, but no matter what I do there seems to be NO response at all from RTC. I even ...
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1answer
35 views

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 ...
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1answer
140 views

Cannot perform echo command to load driver for rtc module

I've come across a few tutorials for adding an rtc module to a pi. They all include a step in which you do echo ds1307 0x68 > /sys/class/i2c-adapter/i2c-1/new_device. When I try this, I get a bash: ...
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2answers
554 views

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 ...
3
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1answer
358 views

What is needed to get I²C working with Debian Jessie?

I have a custom system running on a Raspberry Pi B+ V1.2, based on Debian Jessie (buildroot, systemd, udev) - not Raspbian - and a custom built 3.19.3 Kernel chainloaded by U-Boot and a custom init ...
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3answers
185 views

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 ...
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3answers
2k views

How to install Real TIme Clock (RTC) on Raspian

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 ...
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3answers
305 views

Real Time Clock Module Will it fry my pi?

I bought this RTC module on ebay for pennies. I initially bought it for the arduino but now I would like to use it with the pi. However, I know that in some cases you need logic level converters to ...
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1answer
91 views

Is there a way to connect an I2C RTC using pins 17,19,21,23,25?

I've been looking at I2C RTC modules like this one, but they all appear to be normally connected to pins 1,3,5,7,9. However, I'd also like to try to use a RaZberry Z-wave module on the same Rasberry ...
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2answers
279 views

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 ...
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2answers
421 views

Rasclock does not store the time

I just received my Rasclock V4, and set it up according to Afterthought's instructions. Seeing as I'm doing this on a RPi B+, with the latest raspbian image downloaded from raspberrypi.org just ...
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1answer
71 views

Stackable real time clock?

I'm using Pibrella on my Pi (Model B+) and now I need RTC functionality. Are there stackable RTC modules that you know of? Any help is greatly appreciated. Regards, Kevin
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1answer
156 views

Raspberry Pi with gertduino to use the rtc

I just setup my raspberry pi with the gertduino and I tried the given blink example. It works fine and now I wanted to use the rtc from the gertduino to set the time from the raspberry. How ever I ...
2
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0answers
455 views

Why is my RTC DS1307 not being recognized?

I'm trying to wire up a DS1307 RTC to my Model B Pi. I'm following the diagram as shown in this crude image and I've also tried it like this but it isn't recognized by the Pi. When I run i2cdetect -...
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0answers
204 views

Should I remove fake-hwclock because my i2c RTC isn't always plugged in?

I have a i2c RTC (rtc-pcf8563) that runs great, but I don't always have it plugged in; is there a way to test to see if the RTC is plugged in and, if not, start fake-hwclock or will I have to dpkg ...
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3answers
339 views

Connecting RTC DS1037, Pin 5 already occupied

I think of adding a RTC Module to my Raspberry Pi. I found the following tutorial. http://www.forum-raspberrypi.de/Thread-tutorial-realtime-clock-rtc-ds1307-am-raspberry-pi-betreiben In general it's ...
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2answers
3k views

How to connect DS1307 5V Real time clock (RTC) to 3.3V?

I have DS1307 small SMD parts so I can't simply leave out the resistors easily to make it work with 3.3V by default as with adafruit kit tutorial. How could I connect this device to my Raspberry Pi ...
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1answer
1k views

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?
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1answer
294 views

Raspbian Kernel panic after RTC module .ko - How to unload modules at boot time?

I am playing with the RasClock RTC module. After baking my own rtc-pcf2127a.ko, and following the tutorial from the website, I got a kernel panic when booting (Null pointer etc.) Could not find any ...
0
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1answer
274 views

LCD with RTC and GPS

I have purchased a LCD board, a real time clock board, and a GPS board. I have soldered the LCD onto the breakout board as instructed and put the realtime clock together following the tutorials. At ...
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4answers
8k views

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 up: http://learn....
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1answer
3k views

What does UU mean for RasClock

I acquired a RasClock made by After Thought Software (http://afterthoughtsoftware.com/products/rasclock) . This is a real time clock using i2c. I wanted to play with its other features via i2c but ...
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3answers
3k views

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 ...
0
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1answer
213 views

Determining if network time has been set [duplicate]

I want to add a h/w rtc to my RPi. If network time is available, I want to determine this, and use it to set the system time and also update my own rtc. How can I find if network time is ( or becomes )...
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2answers
2k views

Configuring to read RTC at boot time

I have added an RTC to the I2C bus of the Raspberry Pi. If I follow the steps mentioned here (I am using the DS1307 RTC IC), I can run hwclock and read the time. root@raspberrypi:~# modprobe rtc-...