The DS3231 module sold for the Arduino is perfect for the Raspberry Pi because the IC operates from a range of +2.3 to 5.5 V. This permits the Pi user to power it from the Pi’s +3.3 V supply and wire it up to the I2C bus. The module sports a battery backup, allowing it to keep accurate time when the Pi is powered off. The DS3231 includes temperature measurement and adjustment to maintain timekeeping accuracy.
This chapter will exercise the DS3231 with a C program to set and read the date/time. Additionally, there is a 1 Hz output that can be sensed from a GPIO port should you have application ...
