AVR-Chat

At 02:22 PM 5/04/2006, you wrote:
>If you want to first check your CKOPT fuse (the default is UNCHECKED,
>CHECK IT!!!!) that will fix a lot of problems.

The data sheet is VERY clear that the CKOPT fuse must be set ( i.e. 0)
for clock speeds higher than 8 MHz.

I must say that I have never had any problems so far with it unchecked
HOWEVER my crystal frequency has been 8MHz for all my boards up to now,
no need for speed here :-) I think 8MHz is far too fast, in fact I have
had one application (IDE Interface) where I had to introduce lots of nops
to slow it down because the CDROM could not keep up with the AVR :-D

So all you "speedy gonzales" out there remember to check the CKOPT fuse
if you MUST run above 8MHz....that reminds me to check it in my new
Mega64 board which has a 16MHz crystal just for the heck of it
(not in production yet) :-D

Regards

John Samperi

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Email: john@ampertronics.com.au
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