I am trying to run an ATMega328 at 1 MHz to conserve battery power.
For the program I'm running on it, 8 MHz is a waste of power. 1 MHz should be enough.
But the internal oscillator for ATMega328 has only one frequency to be set: 8 MHz. (While working with ATMega16, I've seen a host of clock speed options: 1 MHz, 2 MHz, 4 MHz and 8 MHz.)
There is another option for the 328: Divide the clock by 8.
I was wondering, would this option get the MCU running at 1 MHz and most importantly, reduced power consumption like running ATMega16 at 1 MHz (without Clock Divide Fuse)?
Or does this option simply runs the MCU oscillator at 8 MHz, consumes as much power as at 8 MHz, but executes instructions at 1 MHz speed?