Very low power LED firefly

I haven’t been able to get anything close to what I wanted for battery life, so I finally sat down and ran the numbers to see what is realistic. Turns out two weeks is about it, given the current state of the project. The ATtiny13A consumes 1.5 mA in active mode at 4.8 MHz clock (which is what my test firmware used) and .004 mA in power-down mode with the WDT enabled; these are the two modes used in my design.”

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