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Author Topic: Recommended fuses for Atmega2560?  (Read 613 times)
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A week or so ago someone suggested changing the fuse on the Atmega2560 to be different from the default because that caused problems with serial communications.

I am having that exact issue with a stand-alone processor, but can't find that post for the life of me.

I'm currently using:

Code:
LFuse = 0xF7
HFuse = 0xD8
EFuse = 0xFF

Does someone remember what the recommended setting was (particularly the low fuse: the clock selection)?
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Nick, the version of your programmer I have is using 0xFF as Low Fuse byte for the 2560.

The change we made to 1284 to fix the Serial timing problems was to change from 0xFF to 0xF7 for Full Swing Oscillator.

Could you have possibly already made that change as you said you're now using 0xF7?
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I manually changed the fuse in this case to what sounded, from memory, like what someone had said. Looks like I got it right. Hmm. Still not working though. Oh well, thanks for the confirmation.
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Is that only for the 1284 ?
The 2560 is not the full swing in boards.txt:
mega2560.bootloader.low_fuses=0xFF
mega2560.bootloader.high_fuses=0xD8
mega2560.bootloader.extended_fuses=0xFD

I checked the datasheet and used this, http://www.engbedded.com/fusecalc/

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I'm using that too.

0xFF is the "Ext Crystal Osc" not the "Full Swing Oscillator". I'm wondering about slowly rising power vs fast rising power. Which is which?
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