debugWIRE is a fantastic bit of technology in many recent AVR chips, allowing you to set breakpoints, step through your code, and a bunch of other useful features. All you need is a programmer that supports it – the AVR Dragon for instance.

In the Atmel Studio project, simply set the Debugger/Programmer Interface to debugWIRE.

The only fly in the ointment is that for extremely low-power applications, having the DWEN fuse and thus debugWIRE enabled will prevent the chip from fully sleeping, meaning your device is much more thirsty than expected.

So you set the Debugger/Programmer Interface back to ISP, and try to program your device again; Failure! In fact; CRYPTIC ERROR MESSAGE!

TO CLEAR debugWIRE FROM A CHIP WITHIN Atmel Studio 6:
Start a debug session on the chip, then
Go to the “Debug” menu and select “Disable debugWIRE and close”.

Now you can access the chip using ordinary ISP, and low-power devices will be more frugal.

This may seem an obvious thing, but there are a number of “solutions” floating around, including people advocating hooking HVPP programmers into devices simply to clear DWEN!