@ralphd I believe you and John1993 are saying the same thing...
I'll be posting my finished designs, once I am there.
Potentially considering using a tiny instead of a mega.
Thanks for the pointer about the LiPo. I am aware of this, but didn't think it completely through. I guess I need to use the internal reference voltage for the ADC then (in order to measure the battery voltage and automatically shut off after a threshold).
As the reference of 1.1v is really low, do I use a voltage divider...
Will the 1.1v stay stable over a varying voltage?
@CrossRoads - I'll have to look into that in more detail. I was actually planning to use much slower speeds for my serial link. Thanks for the page number though - I'll check it out when I am at that point.
Yep, I get what you're saying about DTR. They *are* connected to the same pin though, correct?
A risk with LiPo batteries is draining them too death. You will need a cutoff. Depending on what else is in the circuit you may be able to put the processor into Power Down sleep mode (after turning everything off) when the battery voltage reaches the floor.This article has details about draining (and charging)...http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries