@NeverDie Yes, you are correct - it is based on ATMega1284P. So not relevant
My point is that I'd rather stick to the datasheet rather than overclock, but that's just me. And yes I realise that Moteino is overclocking, but the size, voltage and flash are really appealing to me.
@4994james or just use internal vcc measurement as described on the same page. That saves you the voltage divider.
I wrote a convenient library to measure vcc internally : https://github.com/Yveaux/Arduino_Vcc
In deep Sleep the cunsumption is below 19µA, but i have to send with PA_MAX. On some Windows the open/close frequency is verry high, so the battery is to fast emty.
The CR2032 is good, but i want more "lifetime"
@fets So far, I have only built the 5x5 board (but the others should be schematically identical). The only issue I have found so far is that I cannot get the ISP port to work. But I have checked and I have an identical setup on the 1.0 board and that worked, so I suspect the programmer is too weak to drive the net on this one. So it is not a board-issue per se, and might only be an issue on the 5x5 board as routing is the most complex on that one due to the size.