Rescuing my AVR with AVR Dragon

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Hi,

 

I might have bricked my ATmega168a and possible an ATTiny or 2. Lets call these lessons learned. From this post http://www.avrfreaks.net/forum/tutsoft-recovering-locked-out-avr, which is a bit over-my-head, there is a 90% chance I can rescue my AVRs. If I understand correctly, I can use my Dragon over HVSP to reset the fuses, which I think may be the issue. Now for the question; My 168 is on a breadboard; does the 168 require an external crystal with caps?

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"When all else fails, read the directions"

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For what its worth, I added the external crystal with caps, connected the HVSP wires and reprogrammed the fuses :) - wsmileysmileyt! love my dragon.

"When all else fails, read the directions"

Last Edited: Tue. Oct 28, 2014 - 11:58 PM
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Get your terminology right.    A mega168A requires HVPP which is lots of wires.

So does a Tiny2313/4313.

The smaller Tinys use HVSP which is only a few wires.

 

All the same,   none of these chips should ever need HVP of any description unless you set the RSTDISBL fuse.

 

Think of the RSTDISBL fuse as a last resort.    i.e. only use it in a debugged product that you are never going to repair.

 

David.

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Thank you David for the correct. As for why the device was bricked (e.g. why the RSTDISBL fuse was set); I set the LOW, Hi and Extended fuses with the wrong values. Actually I had the Ext and Low values switched...I learned that valuable lesson. 

"When all else fails, read the directions"