I am involve in a project that will measure different environmental parameters through different sensors once per hour. The other time it will be sleeping.
However, i would like to have a led blinking in order to know that it still have enough power and it is alive. I plan to use something like this:http://www.kpsec.freeuk.com/projects/dummy.htm
This explanation is to ask you if i could go over the input voltage from by batteries by connected the circuit of the example to the Vin pin or arduino when it is sleeping? and ground pin?