/*  RX & 3LED   BY M.K
    AT90S2313 4MHz
    2011/4/26-5/13 7-LED     Ver2 6/5 +Timer
    Last Mod 2011/6/6 SW_RX
    Used ROM (bytes): 552 (27%)
*/

sbit LED_0 at PORTD4_bit;
sbit LED_1 at PORTD5_bit;
sbit LED_2 at PORTD6_bit;
sbit dp    at PORTB7_bit;         //Decimal point
sbit Beep  at PORTD2_bit;         //Sound

sbit WDT   at DDD0_bit;
sbit WD    at PORTD0_bit;

unsigned char I_Cunt;
unsigned char Cps,Csec,Cmin,Chour;
unsigned char LED_0Data,LED_1Data;

char     SW_RX(char N_flag){      //1=again 0=single
char     i,R_data,Dummy;
    //
    WDT=0;                        // 0=input
    do{
      do{
         while(WD);               // check 1?
         Delay_us(19);
      }while(~WD);                // 1=over
         Delay_us(20);
    }while(WD);                   // 0=over
 //
    R_data=0;
    Delay_us(16);
    for(i=0;i<8;i++){
       if(WD==1)
          R_data++;
       else
          Dummy++;
       R_data<<1;
       Delay_us(16);
    }
    if(N_flag==1){
       WDT=1;                     // 1=output
       WD=0;
    }
    return(R_data);
}

void  To_7SegLED (char S_Data)
{
     switch(S_Data & 0x0f){
        case 0:
          PORTB=0x3f;
          break;
        case 1:
          PORTB=0x06;
          break;
        case 2:
          PORTB=0x5b;
          break;
        case 3:
          PORTB=0x4f;
          break;
        case 4:
          PORTB=0x66;
          break;
        case 5:
          PORTB=0x6d;
          break;
        case 6:
          PORTB=0x7d;
          break;
        case 7:
          PORTB=0x07;
          break;
        case 8:
          PORTB=0x7f;
          break;
        case 9:
          PORTB=0x6f;
          break;
        default:
          PORTB=0x08;
     }
}

void Timer0_Interrupt() iv IVT_ADDR_TIMER0_OVF0
 {
     I_Cunt++;
//
     if(I_Cunt==1){               // **1
       LED_2=1;                   //OFF
       To_7SegLED(LED_0Data);
       LED_0=0;                   //ON
// Timer
       Cps++;
       if(Cps==82){               //12.28*81=995mSec
          Cps=0;
          Csec++;
          if(Csec==60){           //1Min
             Csec=0;
             Cmin++;
             if((Cmin & 0x0f)==0x0A)
                 Cmin+=6;
             if(Cmin==0x60){
                Cmin=0;
                Chour++;
                if(Chour==9)      //Max
                   Chour=0;
             }
          }
       }
     }

    if(I_Cunt==2){                // *1*
       LED_0=1;                   //OFF
       To_7SegLED(LED_0Data >>4);
       LED_1=0;                   //ON
//
       if(Csec==0){               //data in
          LED_0Data=Cmin;
          LED_1Data=Chour;
       }
    }

    if(I_Cunt==3){                // 1**
       I_Cunt=0;
       LED_1=1;                   //OFF
       To_7SegLED(LED_1Data);
       if((Csec & 1)==1)
          dp=1;
       LED_2=0;                   //ON
    }
}

void main()
 {
    DDRB = 0xFF;                  // 1=out
    PORTB= 0;
    DDRD = 0b11111100;            // 1=out 0=input
    PORTD= 0b11111100;
//
    I_Cunt= 0;                    //I_Cunter Reset
    TCCR0 = 0x03;                 //1/64=16uec
    TCNT0 = 0;                    // 16*256=4mSec
    TOIE0_bit=1;                  // Interrupt on     TIMSK = 2;
    SREG_I_bit = 1;               //                  asm   sei;
//
    Cps=0;                        //clear register
    Csec=0;
    Cmin=0;
    Chour=0;
    LED_1Data=0;                  //Test
    LED_0Data=0;
    //
    while(1){
//    LED_0Data=SW_RX(0);    //5/17 Test
        if(((Cmin==0)|(Cmin==0X30))&&(Csec==0)){
           Beep=~Beep;
           Delay_us(150);          //3.3KHz
        }
    }
}