建议你完整地看一下DS18B20的资料,否则人家给你程序,你不知道如何修改(没有改很难直接用在你的应用中,应为至少你的引脚连接不会是相同的)。
这个芯片用的是独特的一线通信方式,你肯定要搞清楚这是怎么回事。建议你看一下北航的《PIC16系列单片机C程序设计与PROTEUS仿真》一书,书中有一节完整地介绍了这个芯片,包括一线通信,有完整的线路图(好象有十几个一线式芯片串接)和程序。虽然它是针对PIC单片机,但是是用C写的,程序也可以借鉴。
给你试试看
#include
#include
#define uint unsigned int
#define uchar unsigned char
#define delayNOP() {_nop_();_nop_();_nop_();_nop_();}
sbit DQ = P3^3;
sbit LCD_RS = P2^0;
sbit LCD_RW = P2^1;
sbit LCD_EN = P2^2;
uchar code Temp_Disp_Title[]={"Current Temp : "};
uchar Current_Temp_Display_Buffer[]={" TEMP: "};
uchar code Temperature_Char[8] =
{
0x0c,0x12,0x12,0x0c,0x00,0x00,0x00,0x00
};
uchar code df_Table[]=
{
0,1,1,2,3,3,4,4,5,6,6,7,8,8,9,9
};
uchar CurrentT = 0;
uchar Temp_Value[]={0x00,0x00};
uchar Display_Digit[]={0,0,0,0};
bit DS18B20_IS_OK = 1;
void DelayXus(uint x)
{
uchar i;
while(x--)
{
for(i=0;i<200;i++);
}
}
bit LCD_Busy_Check()
{
bit result;
LCD_RS = 0;
LCD_RW = 1;
LCD_EN = 1;
delayNOP();
result = (bit)(P0&0x80);
LCD_EN=0;
return result;
}
void Write_LCD_Command(uchar cmd)
{
while(LCD_Busy_Check());
LCD_RS = 0;
LCD_RW = 0;
LCD_EN = 0;
_nop_();
_nop_();
P0 = cmd;
delayNOP();
LCD_EN = 1;
delayNOP();
LCD_EN = 0;
}
void Write_LCD_Data(uchar dat)
{
while(LCD_Busy_Check());
LCD_RS = 1;
LCD_RW = 0;
LCD_EN = 0;
P0 = dat;
delayNOP();
LCD_EN = 1;
delayNOP();
LCD_EN = 0;
}
void LCD_Initialise()
{
Write_LCD_Command(0x01);
DelayXus(5);
Write_LCD_Command(0x38);
DelayXus(5);
Write_LCD_Command(0x0c);
DelayXus(5);
Write_LCD_Command(0x06);
DelayXus(5);
}
void Set_LCD_POS(uchar pos)
{
Write_LCD_Command(pos|0x80);
}
void Delay(uint x)
{
while(--x);
}
uchar Init_DS18B20()
{
uchar status;
DQ = 1;
Delay(8);
DQ = 0;
Delay(90);
DQ = 1;
Delay(8);
DQ = 1;
return status;
}
uchar ReadOneByte()
{
uchar i,dat=0;
DQ = 1;
_nop_();
for(i=0;i<8;i++)
{
DQ = 0;
dat >>= 1;
DQ = 1;
_nop_();
_nop_();
if(DQ)
dat |= 0X80;
Delay(30);
DQ = 1;
}
return dat;
}
void WriteOneByte(uchar dat)
{
uchar i;
for(i=0;i<8;i++)
{
DQ = 0;
DQ = dat& 0x01;
Delay(5);
DQ = 1;
dat >>= 1;
}
}
void Read_Temperature()
{
if(Init_DS18B20()==1)
DS18B20_IS_OK=0;
else
{
WriteOneByte(0xcc);
WriteOneByte(0x44);
Init_DS18B20();
WriteOneByte(0xcc);
WriteOneByte(0xbe);
Temp_Value[0] = ReadOneByte();
Temp_Value[1] = ReadOneByte();
DS18B20_IS_OK=1;
}
}
void Display_Temperature()
{
uchar i;
uchar t = 150, 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_Table[Temp_Value[0]&0x0f];
CurrentT = ((Temp_Value[0]&0xf0)>>4) | ((Temp_Value[1]&0x07)<<4);
Display_Digit[3] = CurrentT/100;
Display_Digit[2] = CurrentT%100/10;
Display_Digit[1] = CurrentT%10;
Current_Temp_Display_Buffer[11] = Display_Digit[0] + '0';
Current_Temp_Display_Buffer[10] = '.';
Current_Temp_Display_Buffer[9] = Display_Digit[1] + '0';
Current_Temp_Display_Buffer[8] = Display_Digit[2] + '0';
Current_Temp_Display_Buffer[7] = Display_Digit[3] + '0';
if(Display_Digit[3] == 0)
Current_Temp_Display_Buffer[7] = ' ';
if(Display_Digit[2] == 0&&Display_Digit[3]==0)
Current_Temp_Display_Buffer[8] = ' ';
if(ng)
{
if(Current_Temp_Display_Buffer[8] == ' ')
Current_Temp_Display_Buffer[8] = '-';
else if(Current_Temp_Display_Buffer[7] == ' ')
Current_Temp_Display_Buffer[7] = '-';
else
Current_Temp_Display_Buffer[6] = '-';
}
Set_LCD_POS(0x00);
for(i=0;i<16;i++)
{
Write_LCD_Data(Temp_Disp_Title[i]);
}
Set_LCD_POS(0x40);
for(i=0;i<16;i++)
{
Write_LCD_Data(Current_Temp_Display_Buffer[i]);
}
Set_LCD_POS(0x4d);
Write_LCD_Data(0x00);
Set_LCD_POS(0x4e);
Write_LCD_Data('C');
}
void main()
{
LCD_Initialise();
Read_Temperature();
Delay(50000);
Delay(50000);
while(1)
{
Read_Temperature();
if(DS18B20_IS_OK)
Display_Temperature();
DelayXus(100);
}
}
给我你的邮箱,我有完整可用的18B20单片机及其上位机程序