I am using the code for sleep mode found on: Arduino, Zigbee and Embedded Development: Sleeping Arduino - Part 4 Wake Up Via Internal Timer. My device is a ATmega328.
The timer and interrupt work, but I do not believe that my device is actually going to sleep. How I understand it, the command sleep_mode() should take the duration that the device is sleeping for, however mine only takes a millisecond or so.
Does anyone else have any experience with this? Any help would be appreciated.