Possible to "brick" an ATMEGA328 ? ... correct fuse settings question

Hi, is it possible to "brick" an ATMEGA328 with a wrong fuse setting? I have one chip and now my AVRFuse program can't talk to it anymore, can't read the current state of switches, etc. Is there a way to "revive" this?

So I popped out this problem chip, and inserted a new one... was also able to program this chip directly via ICSP successfully.

And the fuse settings I used are:

Low: 0xff High: 0xde Ext: 0x05

Are these values the recommended ones? Thanks.

Yes, especially if the wrong fuse for the cpu clock option is selected. See the ATmega328 data sheet for the fuse definitions.

I program all my 328Ps as an Uno. The fuse settings are found in the boards.txt file:

uno.bootloader.low_fuses=0xff uno.bootloader.high_fuses=0xde uno.bootloader.extended_fuses=0x05

So you seem to have those correct.

Any chance you messed with the lock bits? This is the totally unlocked state: uno.bootloader.unlock_bits=0x3F uno.bootloader.lock_bits=0x0F

The chip is never really totally bricked - you may just need a High Voltage programmer to unlock it (12V, so not all that high, but not something many people have - including me).

There are three easy ways to "brick" the ATmega328p with my ncorrect fuses: You can disable the Serial Programming feature. You can turn off the Reset Pin feature. You can select a system clock that is not implemented.

The clock can be fixed by using the version of ArduinoISP that generates an 8 MHz clock to be connected to the XTL1 pin of the target processor.

The other two require something like the High Voltage Rescue Shield 2 which plugs not an UNO and can use Parallel Programming to erase the chip and reset the fuses.

You can disable the Serial Programming feature.

This fuse can not be changed by serial programming.