thegoodhen:
Alright. You'll need a programmable attenuator and/or amplifier.This is pretty much all, really.
Actually, for reading the voltage, you don't even need that. Just use a simple resistive divider to get the voltage from 15 volts to 5. Something like 3x100k resistor would work well for this, I believe.
This gets you 1024 steps per the whole range, so 1024 steps for 15 volts. 1 step=0.0146 volts, yup, that's within your specs even with lowend resistors.
Why don't you just use a regular multimeter? logging capability, I guess?
Do you have a regular multimeter?
Is it acceptable to do the range switching manually?
I have regular multimeter ,I want to do this for a college project , also what attentuator and amplifier do you suggest.
I was thinking about resistive divider , but what if there will be voltage > 5V at analog pin to the GND , it could destroy the pin or even uC.
Range switching manually is acceptable.