How to best sort a portion of a circular buffer?

#define _PRINT_PROGRESS
#define N 10
BYTE buff[N]={4,5,2,1,3,5,8,6,4,3};
BYTE *a = buff;
BYTE *b = buff;
BYTE changed = 0;
int main(void)
{
    BYTE n=0;
    do
    {
    	b++;
    	changed = 0;
    	for(n=0;n<(N-1);n++)
    	{
    		if(*a > *b)
    		{
    			*a ^= *b;
    			*b ^= *a;
    			*a ^= *b;
    			changed = 1;
    		}
    		a++;
    		b++;
    	}
    	a = buff;
    	b = buff;
#ifdef _PRINT_PROGRESS
    	for(n=0;n<N;n++)
    		printf("%d",buff[n]);
    	printf("n");
    }
#endif
    while(changed);
    system( "pause" );
}