AVR-Chat

On 30-Jan-11 20:38, Mike Payson wrote:
>
> Most ATMega chips are only rated for 16MHz+ speeds above 4.5V. If you run
> below that you are limited to a lower maximum speed. Unfortunately that
> tidbit is usually hidden fairly deep into the datasheet, so you really need
> to dig to find it. For example, on the ATMega64A, if you check page 344 of
> the datasheet you see that it is only rated to 10MHz at 3.3V:
> http://www.atmel.com/dyn/resources/prod_documents/doc8160.pdf. That is not
> to say that it would not work with a 16MHz crystal... It might work fine,
> but you may get intermittent bugs or other problems. It is usually better to
> play it safe and run at 5V and level shift to talk to the 3v3 components.



     What could happen if the clock prescaler is set to 1/2 when using 
the 16MHz crystal @ 3.3V?

     Mark Jordan