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Divide by 8? Answered

What is the purpose of using divide by 8 in avr programming?
Without knowing more about this is seems like the long way around.



Best Answer 5 years ago

Because often the resonator/crystal is soldered to the board and cannot be changed, but the crystal uses miniscule amounts of power. By having the chip clock down to 1/8th the speed, it uses considerably less power. Ideal when you want long battery life and don't need many of the high speed features of the chip. (iirc 8mhz is needed if you want to run the UART). If you're doing a simple timer or blink led or automation, 1mhz is way more than enough.

Would it be the same thing if we unchecking the divide by 8 and just run at the 1mhz clock?

Thanks for the answer.

Question is a bit vague. Can you give an example?

As can be seen in the screen shot the  box is checked for divide by 8. If i get this correct, if you set your make file at 8000000 and the divide by eight is also chosen then actual speed is 1000000. What is the reason we do this divide by instead of direct clock speed?