#include <8051.h>#include <stdio.h>#include "hw.h"void main(void) {  unsigned long ms;  unsigned int seconds, oldseconds=ClockTicks()/1000;  printf ("Example using the core timer to generate seconds.\n");  while (1) {    ms=ClockTicks();    seconds=ms/1000;    if (oldseconds!=seconds) {      oldseconds=seconds;      printf ("%02d:%02d.%02d %ld\n", 	      (int)seconds/3600, (int)(seconds/60)%60, 	      (int)seconds%60, ms);    }    if (RI) {      putchar(getchar());      printf("%ld\n\r", ClockTicks());    }  }}