3.2.2 Starting a New GCC Project for AVR® Device

Create a new project by selecting New Project from the Project menu and opening the Project Wizard.
Select C/C++→GCC C Executable Project as a template, specify a project name, select a location, and write a solution name for the project. A file with the same name as the project will, by default, be created and added to the project. It will contain an empty main() function. If you want to change the name of the initial file, edit the main filename afterward. Press OK when you are satisfied with the settings.
Select C/C++→GCC C Static Library Project as a template. Then, specify a project name, select a location, and write a solution name for the project, which creates a Static Library (LIB) project, which is a great way to reuse code.
Tip:
See section Starting a New GCC Static Library Project to learn more about Static Library projects.
A device selection table will appear. Choose the appropriate target platform for your project. To start, you can select the ATxmega128A1 device.
Figure 3-5. Device Selection
The project tree will be set up. Notice that the initial file created in step 2 has been added to the project node. Also, the initial file will be opened in the editor.
To facilitate applications development and verification, you can also use the Driver Selection Wizard, invoked from Project → ASF Wizard...
In the ASF Wizard, you can select which Drivers, Components, and Services you would like to use in the project for the current build architecture and board.

Now, write the following code into the open editor window.

#define MAXINT 200000

int main(void) 
{
    unsigned int t=1000, k=0, l=5, pn=2; 
    unsigned int primes[t];
    primes[0]=2;
    primes[1]=3;

    while (pn < t || primes[pn] < MAXINT)
    {
        for ( k = 0; k <= pn; k++)
        {
            if (l % primes[k] == 0)
			{
                goto otog;
			}
            else 
            {
                if (k == pn)
                    primes[pn++]=l;
            } 
        }
otog:
        l += 2;
    }
    return 0;
}