Automatic school bell using PIC Microcontroller

 Hello and welcome back to Enghme. In this project we will create a fully configurable and automated bell that can be used in schools and colleges. It is made using a microcontroller and other commonly available components, an LCD screen and a keypad.

 

Components of the project: 

 

diagram of the project:

 project code:

#define MENU_KEY 'D'
#define SAVE_EXIT '*'
#define BELL_TIME 60

// LCD module connections
sbit LCD_RS at RB7_bit;
sbit LCD_EN at RB6_bit;
sbit LCD_D4 at RB5_bit;
sbit LCD_D5 at RB4_bit;
sbit LCD_D6 at RB3_bit;
sbit LCD_D7 at RB2_bit;

sbit LCD_RS_Direction at TRISB7_bit;
sbit LCD_EN_Direction at TRISB6_bit;
sbit LCD_D4_Direction at TRISB5_bit;
sbit LCD_D5_Direction at TRISB4_bit;
sbit LCD_D6_Direction at TRISB3_bit;
sbit LCD_D7_Direction at TRISB2_bit;
// End LCD module connections

// Keypad Connections
sbit KEY_R1 at LATD0_bit;
sbit KEY_R0 at LATD1_bit;
sbit KEY_R3 at LATD6_bit;
sbit KEY_R2 at LATD7_bit;
sbit KEY_C0 at RD3_bit;
sbit KEY_C1 at RD2_bit;
sbit KEY_C2 at RD4_bit;
sbit KEY_C3 at RD5_bit;

sbit KEY_R1_Direction at TRISD0_bit;
sbit KEY_R0_Direction at TRISD1_bit;
sbit KEY_R3_Direction at TRISD6_bit;
sbit KEY_R2_Direction at TRISD7_bit;
sbit KEY_C0_Direction at TRISD3_bit;
sbit KEY_C1_Direction at TRISD2_bit;
sbit KEY_C2_Direction at TRISD4_bit;
sbit KEY_C3_Direction at TRISD5_bit;
// End Keypad Connections

void keypadInit()
{
  KEY_C0_Direction = 1;
  KEY_C1_Direction = 1;
  KEY_C2_Direction = 1;
  KEY_C3_Direction = 1;

  KEY_R0_Direction = 0;
  KEY_R1_Direction = 0;
  KEY_R2_Direction = 0;
  KEY_R3_Direction = 0;

  KEY_R0 = 1;
  KEY_R1 = 1;
  KEY_R2 = 1;
  KEY_R3 = 1;
}

unsigned readKeypad()
{
  KEY_R0 = 0;
  Delay_ms(1);
  if(KEY_C0 == 0)
  {
    while(KEY_C0 == 0);
    return 1;
  }
  else if(KEY_C1 == 0)
  {
    while(KEY_C1 == 0);
    return 2;
  }
  else if(KEY_C2 == 0)
  {
    while(KEY_C2 == 0);
    return 3;
  }
  else if(KEY_C3 == 0)
  {
    while(KEY_C3 == 0);
    return 4;
  }
  KEY_R0 = 1;

  KEY_R1 = 0;
  Delay_ms(1);
  if(KEY_C0 == 0)
  {
    while(KEY_C0 == 0);
    return 5;
  }
  else if(KEY_C1 == 0)
  {
    while(KEY_C1 == 0);
    return 6;
  }
  else if(KEY_C2 == 0)
  {
    while(KEY_C2 == 0);
    return 7;
  }
  else if(KEY_C3 == 0)
  {
    while(KEY_C3 == 0);
    return 8;
  }

  KEY_R1 = 1;

  KEY_R2 = 0;
  Delay_ms(1);
  if(KEY_C0 == 0)
  {
    while(KEY_C0 == 0);
    return 9;
  }
  else if(KEY_C1 == 0)
  {
    while(KEY_C1 == 0);
    return 10;
  }
  else if(KEY_C2 == 0)
  {
    while(KEY_C2 == 0);
    return 11;
  }
  else if(KEY_C3 == 0)
  {
    while(KEY_C3 == 0);
    return 12;
  }
  KEY_R2 = 1;

  KEY_R3 = 0;
  Delay_ms(1);
  if(KEY_C0 == 0)
  {
    while(KEY_C0 == 0);
    return 13;
  }
  else if(KEY_C1 == 0)
  {
    while(KEY_C1 == 0);
    return 14;
  }
  else if(KEY_C2 == 0)
  {
    while(KEY_C2 == 0);
    return 15;
  }
  else if(KEY_C3 == 0)
  {
    while(KEY_C3 == 0);
    return 16;
  }
  KEY_R3 = 1;
  return 0;
}

unsigned readDS3231(unsigned address)
{
  unsigned short r_data;
  I2C1_Start();
  I2C1_Wr(0xD0); //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0
  I2C1_Wr(address);
  I2C1_Repeated_Start();
  I2C1_Wr(0xD1); //0x68 followed by 1 --> 0xD1
  r_data=I2C1_Rd(0);
  I2C1_Stop();
  return(r_data);
}

void writeDS3231(unsigned address,unsigned w_data)
{
  I2C1_Start(); // issue I2C start signal
  //address 0x68 followed by direction bit (0 for write, 1 for read) 0x68 followed by 0 --> 0xD0
  I2C1_Wr(0xD0); // send byte via I2C (device address + W)
  I2C1_Wr(address); // send byte (address of DS1307 location)
  I2C1_Wr(w_data); // send data (data to be written)
  I2C1_Stop(); // issue I2C stop signal
}

char BCD2UpperCh(unsigned bcd)
{
  return ((char)((bcd >> 4) + '0'));
}

char BCD2LowerCh(unsigned bcd)
{
  return ((char)((bcd & 0x0F) + '0'));
}

unsigned Binary2BCD(unsigned a)
{
  int t1, t2;
  t1 = a%10;
  t1 = t1 & 0x0F;
  a = a/10;
  t2 = a%10;
  t2 = 0x0F & t2;
  t2 = t2 << 4;
  t2 = 0xF0 & t2;
  t1 = t1 | t2;
  return t1;
}

unsigned BCD2Binary(unsigned a)
{
  unsigned r,t;
  t = a & 0x0F;
  r = t;
  a = 0xF0 & a;
  t = a >> 4;
  t = 0x0F & t;
  r = t*10 + r;
  return r;
}

char* getDay(unsigned d)
{
  static char day[10];

  switch(d)
  {
    case 0 : strcpy(day, "Set Time ");
             break;
    case 1 : strcpy(day, "Sunday ");
             break;
    case 2 : strcpy(day, "Monday ");
             break;
    case 3 : strcpy(day, "Tuesday ");
             break;
    case 4 : strcpy(day, "Wednesday");
             break;
    case 5 : strcpy(day, "Thursday ");
             break;
    case 6 : strcpy(day, "Friday ");
             break;
    case 7 : strcpy(day, "Saturday ");
             break;
    default : strcpy(day, "INVALID ");
              break;
  }
  return day;
}

char decodeKeys(unsigned key)
{
  switch(key)
  {
    case 1 : return '6';
    case 2 : return '=';
    case 3 : return '3';
    case 4 : return '9'; //Not Available in 4x3 Keypad
    case 5 : return '*';
    case 6 : return '+';
    case 7 : return '-';
    case 8 : return '/'; //Not Available in 4x3 Keypad
    case 9 : return '5';
    case 10 : return '0';
    case 11 : return '2';
    case 12 : return '8'; //Not Available in 4x3 Keypad
    case 13 : return '4';
    case 14 : return 'N';
    case 15 : return '1';
    case 16 : return '7'; //Not Availabale in 4x3 Keypad
    default : return 0;
  }
}

void main()
{
  unsigned second, minute, hour, hr, day, dday, month, year, bellHour, bellMinute, hourB, minuteB, ls, bt, btLatch;
  unsigned menu = 0, mode = 0, mt, temp, temp2, normalBC, examBC, flag, ah = 0, am = 0, maxBell = 0, bs = 0, bc = 0, bellActive = 0, bellCnt = 0;
  char kp;
  char time[] = "00:00:00 ";
  char date[] = "00-00-00 ";

  ADCON1 = 0x0F;
  TRISA.F0 = 0;
  LATA.F0 = 0;
  I2C1_Init(90000); //DS1307 I2C is running at 50KHz

  keypadInit();

  Lcd_Init(); // Initialize LCD
  Lcd_Cmd(_LCD_CLEAR); // Clear display
  Lcd_Cmd(_LCD_CURSOR_OFF); // Cursor off

  Lcd_Cmd(_LCD_CLEAR); // Clear display
  Lcd_Cmd(_LCD_CURSOR_OFF); // Cursor off
  // Lcd_Cmd(_LCD_BLINK_CURSOR_ON);
  Lcd_out(1,1,"Time:");
  //Lcd_out(2,1,"Date:");

  if(EEPROM_Read(0) == 0xAA)
  {
    normalBC = EEPROM_Read(1);
    examBC = EEPROM_Read(128);
  }
  else
  {
    normalBC = 0;
    examBC = 0;
    EEPROM_Write(1, 0);
    EEPROM_Write(128, 0);
    EEPROM_Write(0, 0xAA);
  }

  bt = 0;

  while(1)
  {
    second = readDS3231(0);
    minute = readDS3231(1);
    hour = readDS3231(2);
    hr = hour & 0b00111111;
    dday = readDS3231(3);
    day = readDS3231(4);
    month = readDS3231(5);
    year = readDS3231(6);

    hourB = BCD2Binary(hour);
    minuteB = BCD2Binary(minute);

    time[0] = BCD2UpperCh(hr);
    time[1] = BCD2LowerCh(hr);
    time[3] = BCD2UpperCh(minute);
    time[4] = BCD2LowerCh(minute);
    time[6] = BCD2UpperCh(second);
    time[7] = BCD2LowerCh(second);

    date[0] = BCD2UpperCh(day);
    date[1] = BCD2LowerCh(day);
    date[3] = BCD2UpperCh(month);
    date[4] = BCD2LowerCh(month);
    date[6] = BCD2UpperCh(year);
    date[7] = BCD2LowerCh(year);

    if(bs == 0)
    {
      if(mode == 0) //Normal Mode
      {
        if(dday != 6) //If Not Friday
        {
          bt = EEPROM_Read(bc*3 + 2);
          if(bt == 0xAA)
            bt = 2;
          else
            bt = 1;

          bellHour = EEPROM_Read(bc*3 + 3);
          bellMinute = EEPROM_Read(bc*3 + 4);
        }
        else //If Friday
        {
          bt = EEPROM_Read(bc*3 + 65);
          if(bt == 0xAA)
            bt = 2;
          else
            bt = 1;
          bellHour = EEPROM_Read(bc*3 + 66);
          bellMinute = EEPROM_Read(bc*3 + 67);
        }
         maxBell = normalBC;
      }
      else if(mode == 1)
      {
        if(dday != 6) //If Not Friday
        {
          bt = EEPROM_Read(129 + bc*3);
          if(bt == 0xAA)
            bt = 2;
          else
            bt = 1;
          bellHour = EEPROM_Read(130 + bc*3);
          bellMinute = EEPROM_Read(131 + bc*3);
        }
        else //If Friday
        {
          bt = EEPROM_Read(191 + bc*3);
          if(bt == 0xAA)
            bt = 2;
          else
            bt = 1;
          bellHour = EEPROM_Read(192 + bc*3);
          bellMinute = EEPROM_Read(193 + bc*3);
        }
        maxBell = examBC;
      }
      if(bellHour < hourB)
        bc++;
      else if(bellMinute <= minuteB)
        bc++;
      else
      {
        bs = 1;
        bc++;
      }

      if(bc > maxBell)
        bc = 0;
      }
      else
      {
        if(hourB >= bellHour)
        {
          if(minuteB >= bellMinute)
          {
            bellActive = 1;
            btLatch = bt;
            bs = 0;
          }
        }
      }

      if(bellActive == 1)
      {
        LATA.F0 = 1;
        bellCnt++;
        Delay_ms(2);
        if(bellCnt > (BELL_TIME * btLatch))
        {
          bellActive = 0;
          bellCnt = 0;
        }
      }
      else
      {
        LATA.F0 = 0;
        bellCnt = 0;
      }

      kp = decodeKeys(readKeypad()); //Read Keypad

      if(kp == MENU_KEY) //Menu Selection via * button
      {
        menu++;
        mt = 0;
        if(menu > 5)
          menu = 0;
        }
        else if(isdigit(kp)) //If numberic value press
        {
          if(menu)
          {
            mt++;
            flag = 1;
          }
        }
        else if(kp == SAVE_EXIT) //Exit or Change Mode when # Pressed
        {
          if(menu)
            menu = 0; //Exit settings
          else
            mode = !mode; //Change Mode
          mt = 0;
        }

        if(menu == 0)
        {
          Lcd_out(1,1,"Time:");
          Lcd_out(1, 6, time);
          if(mode == 0)
            Lcd_out(2, 1, "NORMAL:");
          else
            Lcd_out(2, 1, "EXAM :");

          Lcd_out(2, 8, getDay(dday));
        }
        else if(menu == 1) //Set Time
        {
          Lcd_Out(1, 1, "Set Time ");
          Lcd_Out(2, 1, "Time: ");
          Lcd_Out(2, 7, time);
          if(mt && kp)
          {
            if(mt == 1 && kp < '3')
            {
              Lcd_Out(1,1,0);
              hour = 0x3F & BCD2Binary(hr);
              temp = hour % 10;
              hour = (kp - 48)*10 + temp;
              if(hour > 23)
                hour = 23;
              hour = Binary2BCD(hour);
                hour = hour & 0x3F;
              writeDS3231(2, hour);
            }
            else if(mt == 2)
            {
              hour = 0x3F & BCD2Binary(hr);
              hour = hour/10;
              hour = hour*10 + (kp - 48);
              hour = hour & 0x3F;
              if(hour < 24)
              {
                hour = Binary2BCD(hour);
                writeDS3231(2, hour);
              }
            }
            else if(mt == 3 && kp < '6')
            {
              minute = BCD2Binary(minute);
              temp = minute % 10;

              minute = (kp - 48)*10 + temp;
              minute = Binary2BCD(minute);
              writeDS3231(1, minute);
            }
            else if(mt == 4)
            {
              minute = BCD2Binary(minute);
              minute = minute/10;
              minute = minute*10 + (kp - 48);
              if(minute < 60)
              {
                minute = Binary2BCD(minute);
                writeDS3231(1, minute);
              }
            }
            else if(mt == 5)
            {
              second = 0;
              writeDS3231(0, second);
              menu = 0;
              mt = 0;
            }
          }
        }
        else if(menu == 2) // Set Date
        {
          Lcd_Out(1, 1, "Set Date ");
          Lcd_Out(2, 1, "Date: ");
          Lcd_Out(2, 7, date);

          if(mt && kp)
          {
            if(mt == 1 && kp < '4')
            {
              day = BCD2Binary(day);
              temp = day % 10;
              day = (kp - 48)*10 + temp;
              day = Binary2BCD(day);
              writeDS3231(4, day);
            }
            else if(mt == 2)
            {
              day = BCD2Binary(day);
              day = day/10;
              day = day*10 + (kp - 48);
              if(day < 32 && day > 0)
              {
                day = Binary2BCD(day);
                writeDS3231(4, day);
              }
            }
            else if(mt == 3 && kp < '2')
            {
              month = BCD2Binary(month);
              temp = month % 10;
              month = (kp - 48)*10 + temp;
              month = Binary2BCD(month);
              writeDS3231(5, month);
            }
            else if(mt == 4)
            {
              month = BCD2Binary(month);
              month = month/10;
              month = month*10 + (kp - 48);
              if(month < 13 && month > 0)
              {
                month = Binary2BCD(month);
                writeDS3231(5, month);
              }
            }
            else if(mt == 5)
            {
              year = BCD2Binary(year);
              temp = year % 10;
              year = (kp - 48)*10 + temp;
              year = Binary2BCD(year);
              writeDS3231(6, year);
            }
            else if(mt == 6)
            {
              year = BCD2Binary(year);
              year = year/10;
              year = year*10 + (kp - 48);
              year = Binary2BCD(year);
              writeDS3231(6, year);
              menu = 0;
              mt = 0;
            }
          }
        }
        else if(menu == 3) // Set Day
        {
          Lcd_Out(1, 1, "Set Day, SUN 1~7");
          Lcd_Out(2, 1, "Day : ");
          Lcd_out(2, 7, getDay(dday));

          if(mt <= 1)
          {
            if(flag == 1)
            {
              if(kp > '0' && kp < '8')
                writeDS3231(3, (unsigned short)((kp - 48)));
              bs = 0;
              bc = 0;
            }
          }
          else
          {
            mt = 0;
            menu = 0;
          }
        }
        else if(menu == 4) //Normal Bell
        {
          Lcd_Out(1, 1, "Set Normal Bell ");

          if(mt < 3)
          {
            Lcd_Out(2, 1, "Total Bells: ");
            Lcd_Chr(2, 15, (char)(normalBC%10) + 48);
            Lcd_Chr(2, 14, (char)((normalBC/10)%10) + 48);
            if(mt == 1)
            {
              if(flag && kp < '2')
              {
                normalBC = ((kp - 48)*10) + normalBC%10;
                EEPROM_Write(1, normalBC);
                flag = 0;
                bs = 0;
                bc = 0;
              }
            }
            else if(mt == 2)
            {
              if(flag)
              {
                temp = ((normalBC/10)*10) + (kp - 48);
                if(temp < 17)
                {
                  normalBC = temp;
                  EEPROM_Write(1, normalBC);
                  flag = 0;
                  bs = 0;
                  bc = 0;
                }
              }
            }
          }
          else if(mt <= (2 + normalBC*6)) //Normal Not Friday
          {
            temp = ((mt - 3)/6);
            temp2 = ((mt - 3)%6);
            if(temp <= normalBC)
            {
              if(temp2 == 0)
              {
                if(flag)
                {
                  ls = EEPROM_Read(temp*3 + 2);
                  ah = EEPROM_Read(temp*3 + 3);
                  am = EEPROM_Read(temp*3 + 4);
                  flag = 0;
                }
              }
              else if(temp2 == 1)
              {
                if(flag)
                {
                  if(kp == '1')
                    ls = 0xAA;
                  else
                    ls = 0x00;
                  EEPROM_Write((temp*3 + 2), ls);
                  flag = 0;
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 2)
              {
                if(flag)
                {
                  ah = ((kp - 48)*10) + ah%10;
                  flag = 0;
                  EEPROM_Write(((temp*3) + 3), ah);
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 3)
              {
                if(flag)
                {
                  ah = ((ah/10)*10) + (kp - 48);
                  flag = 0;
                  EEPROM_Write(((temp*3) + 3), ah);
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 4)
              {
                if(flag)
                {
                  am = ((kp - 48)*10) + am%10;
                  flag = 0;
                  EEPROM_Write(((temp*3) + 4), am);
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 5)
              {
                if(flag)
                {
                  am = ((am/10)*10) + (kp - 48);
                  flag = 0;
                  EEPROM_Write(((temp*3) + 4), am);
                  bs = 0;
                  bc = 0;
                }
              }
              Lcd_Out(2, 1, "NDbell : - ");
              Lcd_Chr(2, 8, (temp%10) + 48);
              Lcd_Chr(2, 7, (temp/10) + 48);
              if(ls == 0xAA)
                Lcd_Chr(2, 10, 'L');
              else
                Lcd_Chr(2, 10, 'S');

              Lcd_Chr(2, 12, (ah/10) + 48);
              Lcd_Chr(2, 13, (ah%10) + 48);

              Lcd_Chr(2, 15, (am/10) + 48);
              Lcd_Chr(2, 16, (am%10) + 48);
            }
            else
            {
              mt = 0;
              menu = 0;
            }
          }
          else if(mt <= (2 + 2*normalBC*6)) //Normal Friday
          {
            temp = ((mt - 3 - normalBC*6)/6);
            temp2 = ((mt - 3)%6);
            if(temp <= normalBC)
            {
              if(temp2 == 0)
              {
                if(flag)
                {
                  ls = EEPROM_Read(temp*3 + 65);
                  ah = EEPROM_Read(temp*3 + 66);
                  am = EEPROM_Read(temp*3 + 67);
                  flag = 0;
                }
              }
              else if(temp2 == 1)
              {
                if(flag)
                {
                  if(kp == '1')
                    ls = 0xAA;
                  else
                    ls = 0x00;
                  EEPROM_Write(temp*3 + 65, ls);
                  flag = 0;
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 2)
              {
                if(flag)
                {
                  ah = ((kp - 48)*10) + ah%10;
                  flag = 0;
                  EEPROM_Write(temp*3 + 66, ah);
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 3)
              {
                if(flag)
                {
                  ah = ((ah/10)*10) + (kp - 48);
                  flag = 0;
                  EEPROM_Write(temp*3 + 66, ah);
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 4)
              {
                if(flag)
                {
                  am = ((kp - 48)*10) + am%10;
                  flag = 0;
                  EEPROM_Write((temp*3 + 67), am);
                  bs = 0;
                  bc = 0;
                }
              }
              else if(temp2 == 5)
              {
                if(flag)
                {
                  am = ((am/10)*10) + (kp - 48);
                  flag = 0;
                  EEPROM_Write((temp*3 + 67), am);
                  bs = 0;
                  bc = 0;
                }
              }
              else
              {
                mt = 0;
                menu = 0;
              }
            }
            Lcd_Out(2, 1, "FDbell : - ");
            Lcd_Chr(2, 8, (temp%10) + 48);
            Lcd_Chr(2, 7, (temp/10) + 48);
            if(ls == 0xAA)
              Lcd_Chr(2, 10, 'L');
            else
              Lcd_Chr(2, 10, 'S');

            Lcd_Chr(2, 12, (ah/10) + 48);
            Lcd_Chr(2, 13, (ah%10) + 48);

            Lcd_Chr(2, 15, (am/10) + 48);
            Lcd_Chr(2, 16, (am%10) + 48);
          }
          else
          {
            mt = 0;
            menu = 0;
          }
        }
        else if(menu == 5) //Exam Bell
        {
          Lcd_Out(1, 1, "Set Exam Bell ");

          if(mt < 3)
          {
            Lcd_Out(2, 1, "Total Bells: ");
            Lcd_Chr(2, 15, (char)(examBC%10) + 48);
            Lcd_Chr(2, 14, (char)((examBC/10)%10) + 48);
            if(mt == 1)
            {
              if(flag && kp < '2')
              {
                examBC = ((kp - 48)*10) + examBC%10;
                EEPROM_Write(128, examBC);
                flag = 0;
                bs = 0;
                bc = 0;
              }
            }
            else if(mt == 2)
            {
              if(flag)
              {
                temp = ((examBC/10)*10) + (kp - 48);
                if(temp < 17)
                {
                  examBC = temp;
                  EEPROM_Write(128, examBC);
                  flag = 0;
                  bs = 0;
                  bc = 0;
                }
              }
            }
          }
          else if(mt <= (2 + examBC*6))
          {
            temp = ((mt - 3)/6);
            temp2 = ((mt - 3)%6);
            if(temp <= examBC)
            {
              if(temp2 == 0)
              {
                if(flag)
                {
                  ls = EEPROM_Read(129 + temp*3);
                  ah = EEPROM_Read(130 + temp*3);
                  am = EEPROM_Read(131 + temp*3);
                  flag = 0;
                }
              }
              else if(temp2 == 1)
              {
              if(flag)
              {
                if(kp == '1')
                ls = 0xAA;
              else
                ls = 0x00;
              EEPROM_Write(temp*3 + 129, ls);
              flag = 0;
              bs = 0;
              bc = 0;
            }
          }
          else if(temp2 == 2)
          {
            if(flag)
            {
              ah = ((kp - 48)*10) + ah%10;
              flag = 0;
              EEPROM_Write((130 + temp*3), ah);
              bs = 0;
              bc = 0;
            }
          }
          else if(temp2 == 3)
          {
            if(flag)
            {
              ah = ((ah/10)*10) + (kp - 48);
              flag = 0;
              EEPROM_Write((130 + temp*3), ah);
              bs = 0;
              bc = 0;
            }
          }
          else if(temp2 == 4)
          {
            if(flag)
            {
              am = ((kp - 48)*10) + am%10;
              flag = 0;
              EEPROM_Write((131 + temp*3), am);
              bs = 0;
              bc = 0;
            }
          }
          else if(temp2 == 5)
          {
            if(flag)
            {
              am = ((am/10)*10) + (kp - 48);
              flag = 0;
              EEPROM_Write((131 + temp*3), am);
              bs = 0;
              bc = 0;
            }
          }
          Lcd_Out(2, 1, "NDbell : - ");
          Lcd_Chr(2, 8, (temp%10) + 48);
          Lcd_Chr(2, 7, (temp/10) + 48);
          if(ls == 0xAA)
            Lcd_Chr(2, 10, 'L');
          else
            Lcd_Chr(2, 10, 'S');

            Lcd_Chr(2, 12, (ah/10) + 48);
            Lcd_Chr(2, 13, (ah%10) + 48);

            Lcd_Chr(2, 15, (am/10) + 48);
            Lcd_Chr(2, 16, (am%10) + 48);
          }
          else
          {
            mt = 0;
            menu = 0;
          }
        }
        else if(mt <= (2 + 2*examBC*6))
        {
          temp = ((mt - 3 - examBC*6)/6);
          temp2 = ((mt - 3)%6);
          if(temp <= examBC)
          {
            if(temp2 == 0)
            {
              if(flag)
              {
                ls = EEPROM_Read(191 + temp*3);
                ah = EEPROM_Read(192 + temp*3);
                am = EEPROM_Read(193 + temp*3);
                flag = 0;
              }
            }
            else if(temp2 == 1)
            {
              if(flag)
              {
                if(kp == '1')
                  ls = 0xAA;
                else
                  ls = 0x00;
                EEPROM_Write((191 + temp*3), ls);
                flag = 0;
                bs = 0;
                bc = 0;
              }
            }
            else if(temp2 == 2)
            {
              if(flag)
              {
                ah = ((kp - 48)*10) + ah%10;
                flag = 0;
                EEPROM_Write((192 + temp*3), ah);
                bs = 0;
                bc = 0;
              }
            }
            else if(temp2 == 3)
            {
              if(flag)
              {
                ah = ((ah/10)*10) + (kp - 48);
                flag = 0;
                EEPROM_Write((192 + temp*3), ah);
                bs = 0;
                bc = 0;
              }
            }
            else if(temp2 == 4)
            {
              if(flag)
              {
                am = ((kp - 48)*10) + am%10;
                flag = 0;
                EEPROM_Write((193 + temp*3), am);
                bs = 0;
                bc = 0;
              }
            }
            else if(temp2 == 5)
            {
              if(flag)
              {
                am = ((am/10)*10) + (kp - 48);
                flag = 0;
                EEPROM_Write((193 + temp*3), am);
                bs = 0;
                bc = 0;
              }
            }
            else
            {
              mt = 0;
              menu = 0;
            }
          }
          Lcd_Out(2, 1, "FDbell : - ");
          Lcd_Chr(2, 8, (temp%10) + 48);
          Lcd_Chr(2, 7, (temp/10) + 48);
          if(ls == 0xAA)
            Lcd_Chr(2, 10, 'L');
          else
            Lcd_Chr(2, 10, 'S');

          Lcd_Chr(2, 12, (ah/10) + 48);
          Lcd_Chr(2, 13, (ah%10) + 48);

          Lcd_Chr(2, 15, (am/10) + 48);
          Lcd_Chr(2, 16, (am%10) + 48);
        }
        else
        {
          mt = 0;
          menu = 0;
        }
      }
    Delay_ms(50);
  }
}
//WWW.enghme.com