Microcontroller tutorial and learning LCD1602 display DS18B20 temperature experiment

#include
typedef  unsigned int uint;
typedef unsigned char  uchar;

sbit LCD_RS=P2^0;
sbit LCD_RW=P2^1;
sbit LCD_EN=P2^2;
sbit DQ=P3^4;
uchar Temp_Value[]={0x00,0x00};
uchar Temp=0;
uchar Display_Digit[]={0,0,0,0};
bit DS18B20_IS_OK=1;
uchar code df_tab[]={0,1,1,2,3,3,4,4,5,6,6,7,8,8,9,9};//decimal fraction
uchar code Display_LINE0[]={" Current Temp:"};
uchar Display_LINE1[]={" Temp:          "};

void _delay_ms(unsigned int x)
{
 unsigned char i;
 while(x--)
 {
  for(i=0;i<125;i++);
 }
}

void _delay_us(uint x)
{
 while(--x);
}

bit LCD_Busy(void)//busy detection
{
 bit LCD_Status;//return value variable
 LCD_RS=0;//read status
 LCD_RW=1;
 LCD_EN=1;
 _nop_();_nop_();_nop_();_nop_();
 LCD_Status=(bit)(P0&0x80);
 LCD_EN=0;
 return LCD_Status;
}

void LCD_Write_Command(uchar cmd)//写指令
{
 while(LCD_Busy());
 LCD_RS=0;//
 LCD_RW=0;
 LCD_EN=0;
 _nop_();_nop_();
 P0=cmd;
 _nop_();_nop_();_nop_();_nop_();
 LCD_EN=1;
 _nop_();_nop_();_nop_();_nop_();
 LCD_EN=0;
 
}

void LCD_Write_Data(uchar dat)//write data
{
 while(LCD_Busy());//Busy signal needs to be detected before each data writing operation
 LCD_RS=1;
 LCD_RW=0;
 LCD_EN=0;
 P0=dat;
 _nop_();_nop_();_nop_();_nop_();
 LCD_EN=1;
 _nop_();_nop_();_nop_();_nop_();
 LCD_EN=0;
 
}

void Init_LCD(void)//LCD initialization
{
 _delay_ms(15);//15MS delay
 LCD_Write_Command(0x38);
 _delay_ms(5); 
 LCD_Write_Command(0x38);
 _delay_ms(5); 
 LCD_Write_Command(0x38);//Busy signal needs to be detected before each write command operation
 while(LCD_Busy()); 
 _delay_ms(5);
 LCD_Write_Command(0x01);//Clear screen
 while(LCD_Busy());
 _delay_ms(5);
 LCD_Write_Command(0x38);//Set 16*2 display, 5*7 dot matrix, 8-bit data interface
 _delay_ms(5);
 while(LCD_Busy());
 LCD_Write_Command(0x0c);//Turn on display, no cursor
 _delay_ms(5);
 while(LCD_Busy());
 LCD_Write_Command(0x06); //After reading or writing a character, the address pointer increases by one, and the cursor increases by one
 }

void LCD_POS(uchar pos)//character display position
{
 LCD_Write_Command(0x80|pos);
}

void Show_String(uchar *str)//显示字符串
{
 while(*str!='')
 LCD_Write_Data(*str++);
}
uchar DS18B20_Init(void)
{
 uchar status;
 DQ=1;
 _delay_us(10);
 DQ=0;
 _delay_us(90);
 DQ=1;
 _delay_us(8);
 status=DQ;
 _delay_us(100);
 DQ=1;
 return status;
}
uchar Read_One_Byte(void)
{
 uchar i,dat=0;
 DQ=1;
 _nop_();
 for(i=8;i>0;i--)
 {
  DQ=0;
  dat>>=1;
  DQ=1;
  _nop_();_nop_();
  if(DQ)
   dat|=0x80;
  _delay_us(30);
  DQ=1;
 }
 return dat;
}
void Write_One_Byte(uchar dat)
{
 uchar i;
 for(i=8;i>0;i--)
 {
  DQ=0;
  DQ=dat&0x01;
  _delay_us(5);
  DQ=1;
  dat>>=1;
 }
}

void Read_Temp(void)
{
 if(DS18B20_Init()==1)
  DS18B20_IS_OK=0;
 else
 {
  Write_One_Byte(0xcc);
  Write_One_Byte(0x44);
  DS18B20_Init();
  Write_One_Byte(0xcc);
  Write_One_Byte(0xbe);
  Temp_Value[0]=Read_One_Byte();
  Temp_Value[1]=Read_One_Byte();
  DS18B20_IS_OK=1;
 }
}
void Display_Temperature(void)
{
 uchar ng=0;
 if((Temp_Value[1]&0xf8)==0xf8)
 {
  Temp_Value[1]=~Temp_Value[1];
  Temp_Value[0]=~Temp_Value[0]+1;
  if(Temp_Value[0]==0x00)
  Temp_Value[1]++;
  ng=1;
 }
 Display_Digit[0]=df_tab[Temp_Value[0]&0x0f];
 Temp=((Temp_Value[0]&0xf0)>>4)|((Temp_Value[1]&0x07)<<4);
 Display_Digit[3]=Temp/100;
 Display_Digit[2]=Temp0/10;
 Display_Digit[1]=Temp;
 Display_LINE1[13]=0x43;
 Display_LINE1[12]=0xdf;
 Display_LINE1[11]=Display_Digit[0]+'0';
 Display_LINE1[10]='.';
 Display_LINE1[9]=Display_Digit[1]+'0';
 Display_LINE1[8]=Display_Digit[2]+'0';
 Display_LINE1[7]=Display_Digit[3]+'0';
 if(Display_Digit[3]==0)
  Display_LINE1[7]=' ';
 if(Display_Digit[2]==0&&Display_Digit[3]==0)
  Display_LINE1[8]=' ';
 if(ng)
 {
  if(Display_LINE1[8]==' ')
   Display_LINE1[8]='-';
  else if(Display_LINE1[7]==' ')
   Display_LINE1[7]='-';
  else
   Display_LINE1[6]='-';
 }
 LCD_POS(0);
 Show_String(Display_LINE0);
 LCD_POS(0x40);
 Show_String(Display_LINE1);
}

void main(void)
{
 Init_LCD();
 Read_Temp();
 _delay_ms(1000);
 while(1)
 {
  Read_Temp();
  if(DS18B20_IS_OK)
   Display_Temperature();
  _delay_ms(200);
 }
}