Datasheet

That's all there is to using the DS3231 with CircuitPython! Simply import the DS3231 module, create an instance of the

class, and interact with its datetime property to set and get the time!

Here's a complete example program you can save as main.py on your board and see the time and date printed every

second to the REPL:

# Simple demo of reading and writing the time for the DS3231 real-time clock.

# Change the if False to if True below to set the time, otherwise it will just

# print the current date and time every second. Notice also comments to adjust

# for working with hardware vs. software I2C.

import time

import board

# For hardware I2C (M0 boards) use this line:

import busio as io

# Or for software I2C (ESP8266) use this line instead:

#import bitbangio as io

import adafruit_ds3231

i2c = io.I2C(board.SCL, board.SDA) # Change to the appropriate I2C clock & data

# pins here!

# Create the RTC instance:

rtc = adafruit_ds3231.DS3231(i2c)

# Lookup table for names of days (nicer printing).

days = ("Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday")

#pylint: disable-msg=bad-whitespace

#pylint: disable-msg=using-constant-test

if False: # change to True if you want to set the time!

# year, mon, date, hour, min, sec, wday, yday, isdst

t = time.struct_time((2017, 10, 29, 15, 14, 15, 0, -1, -1))

# you must set year, mon, date, hour, min, sec and weekday

# yearday is not supported, isdst can be set but we don't do anything with it at this time

print("Setting time to:", t) # uncomment for debugging

rtc.datetime = t

print()

#pylint: enable-msg=using-constant-test

#pylint: enable-msg=bad-whitespace

# Main loop:

while True:

t = rtc.datetime

#print(t) # uncomment for debugging

print("The date is {} {}/{}/{}".format(days[int(t.tm_wday)], t.tm_mday, t.tm_mon, t.tm_year))

print("The time is {}:{:02}:{:02}".format(t.tm_hour, t.tm_min, t.tm_sec))

time.sleep(1) # wait a second