I run my 12V car battery trough a trimpot into my pro micro, micro controller. I am using (voltPinValue1 * 0.01465) to get the Volt out of analog in. I have trimmed the pots and getting the right V.
But now I want to calculate for how long I can run for, example the stereo and some LED:s, but don't know how.. Does anybody know how I can do this??
Sorry for my English