Utilizing the watchdog and sleep functions, they put the chip into a hibernation mode between cycles. An optimum configuration could take your battery life from 4 days to about 3 years.

This tutorial takes you through the setup of power saving modes for the Arduino. Utilizing the watchdog and sleep functions, they put the chip into a hibernation mode between cycles.

Arduino: add de-bounce and sleep to short-push-long-push There is an example of a programme that differentiates between long and short push-button pushes on the Arduino.cc website, but I was not taken ...