Thiết kế bộ đo và điều khiển nhiệt độ dùng DS18B20 Lên LCD Sử dụng AT89C51

[thaiban]

CODE Chuẩn:
#include "REGX51.H"
#include "stdio.H"
sbit LCD_RS = P0^0;
sbit LCD_RW = P0^1;
sbit LCD_E = P0^2;
sbit DQ = P3^7;
sbit LCD_D4= P2^4;
sbit LCD_D5= P2^5;
sbit LCD_D6= P2^6;
sbit LCD_D7= P2^7;
#define LINE_1 0x80
#define LINE_2 0xC0
#define CLEAR_LCD 0x01
void delay_ms(unsigned int Time);
void delay_us(unsigned int Time);
// Ham khoi tao DS18b20
//-------------------------------------------------
bit DS18B20_Init()
{
bit presence;
DQ = 0 ;
delay_us(29);
DQ = 1 ;
delay_us(3) ;
presence = DQ ;
delay_us(25) ;
return(presence) ;
}
//=====================================
//========= read bit=================
bit ReadBit(void)
{
unsigned char i=0;
DQ = 0; // pull DQ low to start timeslot
DQ=1;
for (i=0; i<3; i++); // delay 17 us from start of timeslot
return(DQ); // return value of DQ line
}
//==============================================
void WriteBit(bit Dbit)
{
unsigned char i=0;
DQ=0;
DQ = Dbit ? 1:0;
delay_us(5); // delay about 39 uS
DQ = 1;
}
//-------------------------------------------------
// Ham doc 1 byte tu DS18b20 ra ngoai
//-------------------------------------------------
unsigned char ds18b20_readbyte(void)
{
unsigned char i = 0 ;
unsigned char Data = 0 ;
for (i = 0 ; i < 8 ; i++)
{
Data|=ReadBit()? 0x01<<iata;
delay_us(6);
}
return (Data) ;
}

//-------------------------------------------------
// Ham viet 1 byte vao DS18b20
//-------------------------------------------------
void ds18b20_writebyte(unsigned char Data)
{
unsigned char i = 0 ;
for (i = 0 ; i < 8 ; i++)
{
WriteBit((bit)(Data & 0x1));
Data = Data >> 1;
}
delay_us(5);
}

//-------------------------------------------------
// Ham chuyen doi va tra ve gia tri nhiet do do duoc
//-------------------------------------------------
float ds18b20_readtemp(void)
{
float temp;
unsigned char a,b;
DS18B20_Init(); // Khoi tao DS18b20
ds18b20_writebyte(0xCC) ; // Cho phep VDK truy cap thang den cac lenh bo nho cua DS18b20
ds18b20_writebyte(0x44) ; // Khoi dong qua trinh do va chuyen doi nhiet do ra so nhi phan
while (ds18b20_readbyte()==0xff);
DS18B20_Init() ;
ds18b20_writebyte(0xCC) ;
ds18b20_writebyte(0xBE) ; // Cho phep doc du lieu tu bo nho DS18b20 ra ngoai

a = ds18b20_readbyte();
tempfloat)(a&0x0f))/16; // Lay phan thuc cua gia tri nhiet do
b = ds18b20_readbyte();
//a = (int)(a&0xff)*0x100+(b&0xff);
a a&0xf0)>>4)|((b&0x0f)<<4) ; // Lay phan nguyen cua gia tri nhiet do
temp=(float)a;
return temp; // Tra ve gia tri nhiet do
}
// Ham tao xung ENABLE
void lcd1602_enable(void)
{
LCD_E=1;
delay_us(3);
LCD_E=0;
delay_us(5);
}

// --------------------------------------------------
// Ham Gui 4 Bit Du Lieu Ra LCD
void lcd1602_send_4bit_data ( unsigned char cX )
{
LCD_D4 = cX & 0x01;
LCD_D5 = (cX>>1)&1;
LCD_D6 = (cX>>2)&1;
LCD_D7 = (cX>>3)&1;
}

// --------------------------------------------------
// Ham Gui 1 Lenh Cho LCD
void lcd1602_send_command (unsigned char cX )
{
lcd1602_send_4bit_data ( cX >>4 ); // gui 4 bit cao
lcd1602_enable() ;
lcd1602_send_4bit_data ( cX ); // gui 4 bit thap
lcd1602_enable() ;
}

// --------------------------------------------------
// Ham Khoi Tao LCD
void lcd1602_init ( void )
{
lcd1602_send_4bit_data ( 0x00 );
delay_ms(200);

LCD_RS=0;
LCD_RW=0;
LCD_E=0; // che do gui lenh

lcd1602_send_4bit_data ( 0x03 ); // ket noi 8 bit
lcd1602_enable() ;
lcd1602_enable () ;
lcd1602_enable () ;
lcd1602_send_4bit_data ( 0x02 ); // ket noi 4 bit
lcd1602_enable() ;

lcd1602_send_command( 0x2C ); // giao thuc 4 bit, hien thi 2 hang, ki tu 5x8
lcd1602_send_command( 0x80);
lcd1602_send_command( 0x0C); // cho phep hien thi man hinh
lcd1602_send_command( 0x06 ); // tang ID, khong dich khung hinh
lcd1602_send_command( CLEAR_LCD ); // xoa toan bo khung hinh
}

// --------------------------------------------------
// Ham Thiet Lap Vi Tri Con Tro
void lcd1602_gotoxy(unsigned char x, unsigned char y)
{
unsigned char address;
if(!y)
address = (LINE_1+x);
else
address = (LINE_2+x);
delay_ms(3);
lcd1602_send_command(address);
delay_ms(1);
}

// --------------------------------------------------
// Ham Xoa Man Hinh LCD
void lcd1602_clear(void)
{
lcd1602_send_command( CLEAR_LCD );
//delay_us(300);
}

// --------------------------------------------------
// Ham Gui 1 Ky Tu Len LCD
void lcd1602_putchar ( unsigned int cX )
{
LCD_RS=1;
lcd1602_send_command( cX );
LCD_RS=0;
}

// --------------------------------------------------
// Ham Gui 1 Chuoi Ky Tu Len LCD
void lcd1602_puts(char *s)
{
while (*s)
{
lcd1602_putchar(*s);
s++;
}
}

void delay_ms(unsigned int count)
{
unsigned int i;
while(count) {
i = 115;
while(i>0) i--;
count--;
}
}


void delay_us(int us)
{
int i;
for (i=0; i<us; i++);
}

void main()
{
float Nhiet_Do = 30.00;
unsigned char Lcd_Buff[15];

lcd1602_init();
lcd1602_clear();
lcd1602_gotoxy(0,0);
lcd1602_puts(" WELLCOM TO..! ");
lcd1602_gotoxy(0,1);
lcd1602_puts(" HVKTQS ");
delay_ms(3000);
lcd1602_clear();
lcd1602_gotoxy(0,0);
lcd1602_puts("Temperature: ");

while(1)
{
Nhiet_Do = ds18b20_readtemp();
sprintf(Lcd_Buff," TEMP: %2.2f Celcius",Nhiet_Do);
lcd1602_gotoxy(0,1);
lcd1602_puts(Lcd_Buff);
delay_ms(300);
}

}

[JACSION]

hoan hô hay quá

[vnthao]

code bi loi ban oi