int r;
int r = 15;
static void debuggerEditRegister(int n, char **args){  if(n == 3) {    int r;    u32 val;    sscanf(args[1], "%d", &r);    if(r > 16 || r == 15) {      // don't allow PC to change      printf("Error: Register must be valid (0-14,16)\n");      return;    }    sscanf(args[2], "%x", &val);    reg[r].I=val;    printf("Register changed.\n");  } else    debuggerUsage("er");    }