#include <AT89X52.h>

unsigned char code SEGtable[]=
{
        0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e,0x00
};

sbit sw7 = P0 ^ 7;
sbit sw6 = P0 ^ 6;
sbit sw5 = P0 ^ 5;
sbit sw4 = P0 ^ 4;
sbit sw3 = P0 ^ 3;
sbit sw2 = P0 ^ 2;
sbit sw1 = P0 ^ 1;
sbit sw0 = P0 ^ 0;

sbit FMQ = P1 ^ 7;
bit alarmflg = 0;
unsigned RxByte = 0x00;
unsigned char counter = 0;
unsigned char Scounter,Lcounter;  //·Ö±ð´æ·Å×Ô¼ºµÄˮλ״̬ºÍÔ¶·½µÄˮλ״̬
unsigned char FMcounter = 0x02;   //±¨¾¯×´Ì¬²ÎÊý

void DelayFM(unsigned int x)  
{
         unsigned char t;
        while(x--)
        {
                 for(t=0;t<120;t++);
        }
}
//·äÃùÆ÷Çý¶¯º¯Êý£¬²ÎÊýΪ·¢ÉùÉùµ÷
void FM(unsigned char x)
{
         unsigned char i;
        for(i=0;i<100;i++)
        {
                 FMQ = ~FMQ;
                DelayFM(x);
        }
        FMQ = 0;
}

void Delayms(unsigned int MS)   
{
        unsigned int i,j;
        for( i=0;i<MS;i++)
                for(j=0;j<1141;j++);                                
}
void InitUART(void)
{
    TMOD = 0x20;     //9600bps
    SCON = 0x50;
    TH1 = 0xFD;
    TL1 = TH1;
    PCON = 0x00;
    EA = 1;
    ES = 1;
    TR1 = 1;
}
void Send(unsigned char x)
{
  SBUF = x;
  while(TI == 0);
  TI = 0;
}
void Serial(void) interrupt 4 using 1
{
        unsigned char RxByte;
        if(RI == 1)
        {
                RxByte = SBUF;
                RI = 0;
    P2 = RxByte;
    switch(RxByte)
    {
      case 0x00: Lcounter = 0;break;
      case 0xf9: Lcounter = 1;break;
      case 0xa4: Lcounter = 2;break;
      case 0xb0: Lcounter = 3;break;
      case 0x99: Lcounter = 4;break;
      case 0x92: Lcounter = 5;break;
      case 0x82: Lcounter = 6;break;
      case 0xF8: Lcounter = 7;break;
      case 0x80: Lcounter = 8;break;
      default:{};
    }
    if(Scounter > Lcounter)
    {
      if((Scounter - Lcounter) > 2)
      {
        FMcounter = Scounter - Lcounter;
        alarmflg = 1;   
      }
      else
      {
        alarmflg = 0;
      }
    }
    else
    {
      alarmflg = 0;  
    }
        }        
}
int main(void)
{
   InitUART();
   while(1)
   {
     Delayms(100);  
     P0 = 0xFF;
     counter = 0;
     counter = counter + (unsigned char)sw7;
     counter = counter + (unsigned char)sw6;
     counter = counter + (unsigned char)sw5;
     counter = counter + (unsigned char)sw4;
     counter = counter + (unsigned char)sw3;
     counter = counter + (unsigned char)sw2;
     counter = counter + (unsigned char)sw1;
     counter = counter + (unsigned char)sw0;
     Scounter = counter;
     Send(SEGtable[counter]);
     if(alarmflg == 1)
     {
      FM(FMcounter);
     }
   }
}