While it’s certainly possible to roll your own microcontroller clock with the addition of little more than a clock crystal and some assembly language, in this golden age of
inexpensive electronics for DIY, it makes more sense to go
with a dedicated add-on device. This article introduces
you to the world of timekeeping with just such a module:
the popular and inexpensive TinyRTC.
The TinyRTC unit is a complete clock/calendar set to
shoulder all of the timekeeping duties within your circuits.
It’s readily available from a wide range of suppliers for
around six bucks.
You’re going to love the TinyRTC’s features:
• 4096 bytes of EEPROM
• 56 bytes of user RAM
• Rechargeable backup battery
• Communicates effortlessly along the I2C bus
• Dedicated pulse output for interrupt applications
Real time clocks have all sorts of neat uses in microcontroller projects. Most
obvious would be in applications such as alarm clocks, desk calendars,
telescope controllers, smart thermostats, automatic lawn sprinklers, and so
forth. They are also useful for creating timestamps in recordings, logged data
from weather stations, hourly energy usage reports, and much more.
48 April 2015
Add a Real Time
Clock to Your
PIC Projects By Thomas Henry