Real Time Clock Rpi
add a real time clock to the raspberry pi

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Raspberry Pi B and B+ with the RTC 3231

Product Link: http://www.jola.ro/home/729-mini-rtc-raspberry-pi.html from Seeduino

Links:

• http://rpi.fatdog.eu/?p=chronodot-rtc

• http://nicegear.co.nz/blog/using-an-i2c-real-time-clock-rtc-with-a-raspberry-pi/

Connect the module to the inner pins at 3.3 V

apt-get update && apt-get dist-upgrade

rpi-update

apt-get install i2c-tools libi2c-dev ntpdate

sudo i2cdetect -y 1 (1 for b and b+ 0 for a)

sudo vim /etc/modprobe.d/raspi-blacklist.conf

blacklist spi-bcm2708
#blacklist i2c-bcm2708

sudo vim /etc/modules

snd-bcm2835
i2c-bcm2708
i2c-dev
rtc-ds1307

modprobe rtc-ds1307

sudo vim /etc/rc.local

#for B and B+
echo ds3231 0x68 > /sys/class/i2c-adapter/i2c-1/new_device
/sbin/hwclock -s

optional remove fake HW clock:

• sudo update-rc.d -f fake-hwclock remove

• sudo update-rc.d -f ntp remove

sudo reboot

get time from a time server and write it to the real time clock

• sudo ntpdate pool.ntp.org

• sudo hwclock -w

check the time on the module with: sudo hwclock -r

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Posted on:

December 28, 2014
127 words