Computing stuff tied to the physical world

Clock Plug design

In Hardware on Aug 29, 2009 at 00:01

The obvious plug, given that I2C is so easy to do now, is a real time clock based on the DS1307:

Picture 2.png

I’m using a small battery since a CR2032 coin cell is so… large. This board has a 12mm holder – with a 48 mAH BR1225 battery the RTC will run for some 10 years according to Maxim.

As with several of these plugs, boards like the above come a dime a dozen. It isn’t very hard to do – but once you’ve got a convention for pinouts and a physical layout that works, having such boards becomes a great time-saver. Particularly when daisy-chaining I2C plugs.