Temperature measurement DSB1820 lcd1602 liquid crystal display-EEWORLD

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The LCD1602display.h header file used in the program can be obtained from my other article: http://www.51hei.com/mcu/3292.html is the same file
#include
#include
#include "LCD1602display.h"
sbit DQ=P2^0; //ds18b20
uint wendu=0;
uchar num,num1;
uint temperature=0;
uchar code range[]="===TEMPERTURE===";
uchar code ASCII[]="0123456789.";
uchar code table0[]="ROME TEMP:00.0C ";
uchar code table1[]=" ERRO !!! ";
uchar temp[3]={0,0,0};
//********************Delay
void delay1ms(uint z)
{
uint x,y;
for(x=z;x>0;x--)
for(y=114;y>0;y--);
}
//*************************Initialize
bit init_DS18B20()
{
bit flag; //Store the flag of whether DS18B20 exists, flag=0 means it exists; flag=1 means it does not existDQ
=1;
_nop_(); //Pull up
DQ=0 first;
for(num=0;num<200;num++); //Require to maintain 480~960us
DQ=1; //Release data linefor
(num=0;num<10;num++); //Wait for DS18B20 to respondflag
=DQ; //Responsefor
(num=0;num<200;num++); //Delay long enough (this delay function is to prevent entering a dead end due to lack of signal)
DQ=1; //Release data linereturn
(flag); //Return detection success flag
}
//*******************************Write temperature
datavoid DS18B20_WR_CHAR(uchar byte) // Write low bit first
{
for(num1=0;num1<8;num1++)
{
DQ=1;
_nop_();
DQ=0; // Start writing sequence when the data line is pulled down from high to
lowfor(num=0;num<5;num++);//Wait for 15us
DQ=byte&0x01;
for(num=0;num<15;num++); // Delay about 45us, DS18B20 samples from the data line during about 15~45usbyte
>>=1;
for(num=0;num<1;num++);// Delay 3us, at least 1us recovery period is required between two write sequences
}
DQ=1;//Release data line
}
//**********************************Read temperature data
uchar DS18B20_RD_CHAR() // Read low bit first
{
uchar byte=0;
for(num1=0;num1<8;num1++)
{
DQ=1;
_nop_();
DQ=0; //Give a low pulse
_nop_();
DQ=1;
for(num=0;num<5;num++); //Delay about 15us, so that the host can sample within 15us
byte>>=1;
if(DQ==1)
byte|=0x80;
else
byte|=0x00;
for(num=0;num<1;num++);//Delay 3us, there must be a recovery period greater than 1us between the two read timings
} return ( byte )
;
}
//**** ...temperatureh=0; if(init_DS18B20()==0) { DS18B20_WR_CHAR(0xcc); DS18B20_WR_CHAR(0x44); delay1ms(1000); if(init_DS18B20()==0) { DS18B20_WR_CHAR(0xcc); DS18B20_WR_CHAR(0xBE); _nop_ (); temperaturel=DS18B20_RD_CHAR(); temperatureh=DS18B20_RD_CHAR();

temperature=(temperatureh*256+temperaturel)*0.625;
init_DS18B20();
}
//return (temperature);
}
}
//********************** ********Temperature display
void display_DS18B20()
{
temp[2]=temperature/100%10;
temp[1]=temperature%100/10;
temp[0]=temperature%10;

DisplayListChar(0, 1, table0);
DisplayOneChar(10, 1, ASCII[ temp[2] ] );
DisplayOneChar(11, 1, ASCII[ temp[1] ] );
DisplayOneChar(12, 1, ASCII[10] );
DisplayOneChar(13 , 1, ASCII[ temp[0] ] );
}
//************************************Main function
main( )
{
InitLCM();
DisplayListChar(0,0,range);
DisplayListChar(0,1,table0);
while(1)
{
if( init_DS18B20()==0)
{
DS18B20_WENDU();
display_DS18B20();
}
}
}

Keywords：DSB1820 lcd1602 Reference address：Temperature measurement DSB1820 lcd1602 liquid crystal display

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