User manual

AREXX Engineering & JM3 Engineering
Version: 1.05 Nov. 9
th
, 2014 page: 5
Introduction
General purpose Real Time Clock (RTC) module - it can be directly plugged into the ASURO
expansion port on the ASURO xTend - it can be stacked up with other ASURO extension
modules like Compass/Gyro Module.
The module is using the Maxim DS1339 RTC with I2C bus interface. It is a low-power clock/date
device with two programmable time-of-day alarms and a programmable square-wave output. The
device provides the following clock/date information - minutes, hours, day, date, month, and year.
The date at the end of the month is automatically adjusted for months with fewer than 31 days
and corrections for leap year. The clock can operate in 24-hour or 12-hour format with AM/PM
indicator. The built-in power-sense circuit detects power failures and automatically switches to the
backup supply, maintaining time, date, and alarm operation. Internal low drop voltage regulator
and rechargeable backup-battery make the design complete and easy to use. A Trickle-Charger
capability of the DS1339 charges the back-up battery automatically during operation.