liebman
Support for silent clocks
In your blog post you mentioned future work could include support for silent clocks. I went to IKEA and bought a clock and they all seem to be of the silent type. I hooked it up to an oscilloscope to see what it was outputting.
Could you provide any guidance on how to emulate this using the ATtiny85's PWM output and whether this will deplete the battery faster to wake up to do 8Hz ticks?
I played with this and dropped it due to the excess battery drain. It should work. Maybe using C or D cells can give long enough battery life. You will have to play with it and see. Rough calculation says it will use 8x the power.
The other issue is setting the initial time. With 1 hz its easy but with 8 power could drop out 4 "ticks" into a second..... so you will have to keep time in 8ths of a second, which may need changes in the protocol between the esp and the t85.