#include <REG52.H>   
#include <INTRINS.H>   
sbit Beep =  P1^5 ;
unsigned char S_TH[]={
0xFC,0xFC,0xFD,0xFD,0xFD,0XFD,0xFE,0xFE};
unsigned char S_TL[]={
0x44,0xAC,0x09,0x34,0x82,0xC8,0x06,0x22};
unsigned char Tone=0;
/*延时子程序*/
void Delay(int n)  
{
int i,j;
for(i=0;i<n;i++)
{
    for(j=0;j<10;j++)
{
}
}

}
/*定时器0中断服务程序*/
void INT_TO(void) interrupt 1
{
Beep=!Beep;
TH0=S_TH[Tone];
TL0=S_TL[Tone];
}
main()
{
TMOD=0x01;
TH0=S_TH[Tone];
TL0=S_TL[Tone];
Beep=0;
EA=1;
ET0=1;
TR0=1;
Delay(5000);
while(1)
{
  Tone++;
  if(Tone==8)
     Tone=0;
Delay(5000);
}
}

确实看不懂这个程序，求大神解释啊