As you may know, real time clocks have many great benefits. They can keep the current time for a few years if used properly. You can read many articles about how useful they are and why, but right now, I’ll just show you how I got my DS3231 to work with Raspbian Stretch.

So firstly we’ll need to edit the config file.

sudo nano /boot/config.txt

Alright. Now we’re going to add this line to the bottom of the file. This will tell the Raspberry Pi to enable it’s i2c interface and its DS3231 interface

dtoverlay=i2c-rtc,ds3231

Ok. So once we’ve done that, we’ll need to exit the text editor by pressing Control + X, then when prompted to, click Y, then enter.

Alright, so now we’ll need to disable the software RTC. This just keeps the network time. So what we’ll want to do is stop that. So type:

 sudo nano /lib/udev/hwclock-set

Ok. Now find the line:

if [-e /run/systemd/system ]; thenexit 0 
fi

And replace it with

#if [-e /run/systemd/system ]; then
#exit 0 
#fi

Alright. So reboot by typing

sudo reboot

And type

sudo hwclock -r

To see the time If it isn’t correct, type

sudo raspi-config

Go to option 4 (Localization), then go to option I2 and follow the steps. Then type

sudo hwclock -w

And you’re done!

Step 1: Quick Note About My Sponsor

That concludes this post, but the sponsor of this project is PCBWay who, at the time is celebrating their 5th anniversary. Check them out at: https://www.pcbway.com/ and don't forget their assembly service is now as low as $30.