NOTE:
After installing AtmelStudio and WinAVR,
before trying to compile a C program do the following:

Click on Menu “Project”, select item “Configuration Options”,
then go to “Custom Options".

Uncheck the box “Use AVR Toolchain”,
then in the avr-gcc field enter this path (or wherever Winavr is on your PC):
  C:\WinAVR-20100110\bin\avr-gcc.exe
In the “make” field enter:
  C:\WinAVR-20100110\utils\bin\make.exe
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