Will Atmega128L work on external 16Mhz crystal if Vcc=5V???

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I have seen the in the datasheet about the speed grade of atmega128 and 128L....clearly states the difference in speed....
But someone told me that if Vcc=5V to atmega128L then external crystal of 16Mhz will work.....

Is this true ?? :?

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The data sheet says it all. The 128L will work from 0 to 8MHZ period. VCC has nothing to do with it.

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The datasheet is usually correct on this issues.

As for overclocking. The IQ of overclockers is inverse proportional to the speed gain they claim to achieve.

Stealing Proteus doesn't make you an engineer.

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ya, but anyone has tried??

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why would you try to go that far off when you know your problems can become inmense.
it is not a bit overclocking, but a factor of 2. You might get irradical behaviour of your processor so you run a big risk of chasing ghosts because the processor can not handle the speed and misses clocks and or other things ( interrupts/stack retreival/program counter)

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msd wrote:
ya, but anyone has tried??

Yes.
I tried it.
It didn't work.
Also, it somehow managed to conjure up the devil.
The next day, my dog died and my wife left me and I developed a nasty cough.

I think next time I'll try increasing the supply voltage to 12V as well.
And I'll have some tissues at hand to mop up the ectoplasm.

I hope this helps,

John

Four legs good, two legs bad, three legs stable.

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Why not try it yourself?

I have a pretty good idea what the result will be.

If you intend to sell 10,000's of overclocked products, I would advise against it.

David.

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Could it be that anyone else has ever tried to clock an AVR? Let me see...

Search "overclock", category="AVR 8 forums"

Result: 128 hits

So the answer would appear to be "yes"