-
Notifications
You must be signed in to change notification settings - Fork 297
pi RTC with raspbian jessie
Pi with raspbian Jessie and install of RTC
Up until Jessie I have had no problems with an RTC install with Jessie my old methods did not work.
Checking forums found that this was indeed a problem, but after cobbling together information I have the following advice that is working for me.
All of my attempts to install were wound back and any symbolic links generated removed until basically at a fresh Jessie install.
Three main bits of information from Marcus 15, Gordon77, and the README file at the following file location Additional overlays and parameters are documented /boot/overlays/README, specifically at about line 290 for i2c-rtc information.
Jessie now supports out of the box RTC based on ds1307,ds3231,mcp7941x and three others, mine is based on the ds3231.
- After having booted to Jessie UI screen configure basic data as required including enabling i2c.
sudo nano /boot/config.txt
- At the bottom of this file you should now see dtparam=i2c=on
- For my ds3231 unit add the line
dtoverlay=i2c-rtc,ds3231
- Save and exit file
sudo nano /lib/udev/hwclock-set
- comment out the lines
if [ -e /run/system/system ]; then exit 0 fi
- There is no need to add i2c-bcm2708,i2c-dev and rtc-ds1307 to the /etc/modules as before.
- /etc/modprobe.d/raspi-blacklist.conf has nothing in it
- I then got rid of the fake hwclock
sudo apt-get remove --purge fake-hwclock
- Ensure NTP on
timedatectl set-ntp true
- Connected to web check date and time and write to RTC
sudo hwclock –w
- Reboot and check date and time with
timedatectl status
- I then shutdown and removed lan and left off for 2 hrs and checked operation using monitor not ssh in.
- As a final check, unplug the lan and then reboot the pi. This ensures the RTC starts up in the worst case scenario (no network available during initialization.)