C语言里的INT to CHAR*
c语言中int转成char *的函数itoa，标准c里集成，CVAVR里好像没有
void reverse(char *s)
{
char *c;
int i;
c = s + strlen(s) - 1;
while(s < c) {
i = *s;
*s++ = *c;
*c– = i;
}
}
char *itoa(int n,char *s)
{
int sign;
char *ptr;
ptr = s;
if ((sign = n) < 0) n = -n;
do {
*ptr++ = n % 10 + ‘0′;
} while ((n = n / 10) > 0);
if (sign < 0) *ptr++ = ‘-’;
*ptr = ‘ ’;
reverse(s);
return s;
}