//Warteschleife
//-----------------------------------------------------------------------------
void delay(int usec)
{
    int s;
    for(s=0;s<usec;s++);
}

//Reset 1-Wire
//-----------------------------------------------------------------------------
unsigned char ow_reset(void)
{
    unsigned char presence;

    Port_DataDirBit(16,1);     //PortPin16 = Ausgang
    Port_WriteBit(16,0);       //PortPin16 auf "LOW" gesetzt
    delay(29);
    Port_WriteBit(16,1);       //PortPin16 auf "High" gesetzt
    Port_DataDirBit(16,0);     //PortPin16 = Eingang
    Port_WriteBit(16,1);       //Pull-Up Widerstand "ein"
    delay(3);
    presence=Port_ReadBit(16); //presence mit aktuellem Portstatus belegen
    delay(25);
    return(presence);
}

//Schreibt Bit auf 1-Wire-Bus
//-----------------------------------------------------------------------------
void write_bit(char bitval)
{
    Port_DataDirBit(16,1);                  //PortPin16 = Ausgang
    Port_WriteBit(16,0);                    //PortPin16 auf "LOW" gesetzt
    if(bitval==1)Port_WriteBit(16,1);       //PortPin16 auf "High" gesetzt
    delay(5);
    Port_WriteBit(16,1);
}

//Schreibt Byte auf 1-Wire-Bus
//-----------------------------------------------------------------------------
void write_byte(char val)
{
    unsigned char i;
    unsigned char temp;

    for(i=0;i<8;i++)
    {
        temp=val>>i;
        temp = temp & 0x01 ;
        write_bit(temp);
    }
    delay(5);
}

//Liest Bit von 1-Wire-Bus
//-----------------------------------------------------------------------------
unsigned char read_bit(void)
{
    unsigned char i;
    Port_DataDirBit(16,1);    //PortPin16 = Ausgang
    Port_WriteBit(16,0);      //PortPin16 auf "LOW" gesetzt
    Port_WriteBit(16,1);      //PortPin16 auf "High" gesetzt
    for(i=0;i<3;i++);
    Port_DataDirBit(16,0);    //PortPin16 = Eingang
    Port_WriteBit(16,1);      //PortPin16 Pull-Up Widerstand ein
    i=Port_ReadBit(16);
    return(i);
}

//Liest Byte von 1-Wire-Bus
//-----------------------------------------------------------------------------
unsigned char read_byte(void)
{
    unsigned char i;
    unsigned char value;
    value=0;
    for(i=0;i<8;i++)
    {
        if(read_bit())value=value|0x01<<i;
        delay(6);
    }
    return(value);

}

//Liest Temperatur von DS1820
//---------------------------------------------------------------------------
void Read_Temperature(void)
{
    char get[10];
    char temp_lsb,temp_msb;
    int k;
    char temp_f,temp_c;

    ow_reset();
    write_byte(0xCC);                              //Skip ROM
    write_byte(0x44);                              //Conver T

    delay(5);
    ow_reset();
    write_byte(0xCC);                              //Skip ROM
    write_byte(0xBE);                              //Read Scratchpad
    for(k=0;k<9;k++){get[k]=read_byte();}

    temp_msb=get[1];
    temp_lsb=get[0];
     if(temp_msb<=0x80){temp_lsb=(temp_lsb/2);}
    temp_msb=temp_msb&0x80;
     if(temp_msb>=0x80){temp_lsb=((~temp_lsb)+1);}
     if(temp_msb>=0x80){temp_lsb=(temp_lsb/2);}
     if(temp_msb>=0x80){temp_lsb=((-1)*temp_lsb);}
    Msg_WriteChar(temp_lsb);
    LCD_WriteText(get);
}

void main(void)
{
    Read_Temperature();
    LCD_Init();
    LCD_ClearLCD();

}