Accessory Shield User Manual
Waveshare
12
V1.1.6, March 10
th
2015
2.2.7 Extremely accurate real-time clock: DS3231
The DS3231 is a low-cost, extremely accurate I
2
C real-time clock (RTC) with an
integrated temperature compensated crystal oscillator (TCXO) and crystal. The
device incorporates a battery input, and maintains accurate timekeeping when main
power to the device is interrupted. The integration of the crystal resonator enhances
the long-term accuracy of the device.
The RTC maintains seconds, minutes, hours, day, date, month, and year
information. The date at the end of the month is automatically adjusted for months
with fewer than 31 days, including corrections for leap year.
It has the following features:
Operating voltage range: 2.3V to 5.5V;
Operating temperature range:
Commercial: 0
℃
to +70
℃
;
Industrial: -40
℃
to +85
℃
;
Accuracy ±2ppm from 0°C to +40°C;
Accuracy ±3.5ppm from -40
℃
to +85
℃
.
Operation and phenomena:
Perform program compiling and uploading, and then click the button
to start
the serial port monitor of Arduino IDE. This Demo performs two functions: outputting
current time information and setting new time via the serial port.
As the figure shows below:
Arrow 1 points to the position for inputting new time setting. The new time should be
set in a specified format with 15 characters length, such as 020150207143000, in
which the first character is 0, then the followings are the settings of year(2015),
month(02), date(07), hours(14), minutes(30) and seconds(00). When finished the
new time setting, click the button
Send
pointed by Arrow 2. You will see that the
