Hi Hape,

Yes there are lots of articles on the web for advanced users to enable atmel hardware debug

You will also need a cap on the reset line which means you must manually push reset to upload using usb

You can also use "file>open object file for debugging" to debug an existing compiled arduino program

You have some research to do and it's the reason that we have the simpler serial debug. Not always enough for some but ok for most 

Okay thanks for explaining.

The atmel debugger does not understand an .ino project but we hope there will be a release of visual micro over the next month or two that allows for a ".cpp only" arduino project.

When we compile for arduino we copy all of the .ino source code into a temporary [sketch].cpp source file. It is the .cpp that is compiled into a .elf file.

Switch on "tools>options>visual micro>compiler>show build folder" then press F7 or build your arduino project.

After the build the output window will show the name of the temporary build folder.

Atmel studio can debug the .elf file that will exist in the temporary build folder.

Use "File>Open object file for debugging", this is an Atmel Studio feature. It allows you to open the .elf in the build folder described above.

When you open a .elf for debugging a file mapping window will open. The window is more intelligent than it appears to be. Paste folder names to the right side of the mapping window and it will auto complete the file names for you.

After opening the elf for debugging, atmel studio will create a new read-only solution containing the code of the .elf. Save the solution so it can be re-used after making code changes and building your arduino project.

This solution is "clunky" I know. I hope that Visual Micro is able to provide a more seemless solution in the not to distant future