I read the following under "known issuse" in the manual for JTAGICE mkII.
"debugWIRE communication is lost when part code forces the part into reset. BOD, WDT or other reset sources cause the part to lose debugWIRE communication. High voltage programming is required to get communication re-established."
Does this mean that is I use debugWire and get some of the above reset causes, my part is destryed? Or that is actually "high voltage programming" I think on it as parallell programming that must be done in a ZIF socked and not in the target using ordinary ISP.
I wanted to make an application with the ATmega168 that puts the device in power-down mode in idle time and letting the watch-dog wake it up. This will be much more power efficient than using idle mode. But if the above is correct I will not be able to debug my program. A possibility is to use idle mode during debugging but I must still be able to re-enable debugWire without desolder the device.