1602 display dht11 temperature and humidity

agajal

1602 display dht11 temperature and humidity [Copy link]

#include<reg52.h>
#include "intrins.h"
typedef unsigned char uint8;
typedef unsigned int uint16;
sbit rs=P2^6; //Data command selection
sbit rw=P2^5; //Read and write selection
sbit e=P2^7; //Enable

sbit k1=P3^3; //mode
sbit k2=P2^1; //add
sbit k3=P2^2; //subtract

sbit DHT11_DQ_OUT=P3^2;
sbit led1=P3^6;
sbit led2=P3^7;

sbit dq=P2^0;

uint8 mode=0,xian;
char temph=50,templ=20;
char humih=80,humil=20;
uint8 temp,humi;
uint8 flag; //Set alarm flag
uint8 a,c,tempvalue;
uint8 code num[10]="0123456789";

uint8 code str1[]="Temp:"; //Temperature
uint8 code str2[]="Humi:"; //Humidity
uint8 code str3[]="Error";
uint8 code str4[]="Success ";
uint8 code str5[]="%RH";
uint8 code str6[]="TempH:"; //Set the upper limit of temperature display
uint8 code str7[]="TempL:"; //Set the lower limit of temperature display
uint8 code str8[]="HumiH:"; //Set the upper limit of humidity display
uint8 code str9[]="HumiL:"; //Set the lower limit of humidity display

void delay(uint16 i)
{
while(i--);
}

void delay_ms(uint16 i)
{
while(i--)
delay(90);
}

void wrc(uint8 c) //write command
{
delay(1000);
rs=0;
rw=0;
e=0;
P0=c;
e=1;
delay(10);
e=0;
}
void wrd(uint8 dat) //write data
{
delay(1000);
rs=1;
rw=0;
e=0;
P0=dat;
e=1;
delay(10);
e=0;
rs=0;
}
void lcd_init() //LCD1602 initialization
{
delay(1000);
wrc(0x38);
wrc(0x38); //Function setting command, select 8-bit bus, double-line display 5*7 dot matrix characterswrc
(0x38);
wrc(0x06); //Cursor and display mode settings Cursor right move The whole screen does not movewrc
(0x0c); //Display switch control Turn on the display No cursor Cursor does not blink
wrc(0x01); //Clear instruction Fixed
}
//Reset DHT11
void DHT11_Rst()
{
DHT11_DQ_OUT=0; //Pull DQ low
delay_ms(20); //Pull low for at least 18ms
DHT11_DQ_OUT=1; //DQ=1
delay(3); //Host pulls high for 20~40us
}

//Wait for the response from DHT11
//Return 1: DHT11 is not detected
//Return 0: It exists
uint8 DHT11_Check()
{
uint8 retry=0;
while (DHT11_DQ_OUT&&retry<100)//DHT11 will pull down for 40~50us
{
retry++ ; _nop_()
;
};
if(retry>=100)return 1;
else retry=0;
while (!DHT11_DQ_OUT&&retry<100)//DHT11 will pull up again after being pulled down for 40~50us
{
retry++;
_nop_();
};
if(retry>=100)return 1;
return 0;
}

//DHT11 initialization
//Return 0: initialization successful, 1: failure
uint8 DHT11_Init()
{
DHT11_Rst();
return DHT11_Check();
}

//Read a bit from DHT11
//Return value: 1/0
uint8 DHT11_Read_Bit(void)
{
uint8 retry=0;
while(DHT11_DQ_OUT&&retry<100)//Wait for it to become low level for 12-14us start
{
retry++;
_nop_();
}
retry=0;
while((!DHT11_DQ_OUT)&&retry<100)//Wait for it to become high level 26-28us means 0, 116-118us means 1
{
retry++;
_nop_();
}
delay(1);//Wait for 40us
if(DHT11_DQ_OUT)return 1;
else return 0;
}

//Read a byte from DHT11
//Return value: the read data
uint8 DHT11_Read_Byte(void)
{
uint8 i,dat=0;
for (i=0;i<8;i++)
{
dat<<=1;
dat|=DHT11_Read_Bit();
}
return dat;
}

//Read data from DHT11 once
//temp: temperature value (range: 0~50°)
//humi: humidity value (range: 20%~90%)
//Return value: 0, normal; 1, reading failed
uint8 DHT11_Read_Data(uint8 *temp,uint8 *humi)
{
uint8 buf[5];
uint8 i;
DHT11_Rst();
if(DHT11_Check()==0)
{
for(i=0;i<5;i++)//Read 40 bits of data
{
buf=DHT11_Read_Byte();
}
if((buf[0]+buf[1]+buf[2]+buf[3])==buf[4])
{
*humi=buf[0];
*temp=buf[2];
}

}else return 1;
return 0;
}

void ds18b20init() //18b20 initialization
{
dq=1;
delay(1);
dq=0;
delay(80);
dq=1;
delay(5);
dq=0;
delay(20);
dq=1;
delay(35);
}
void ds18b20wr(uint8 dat) //18b20 write data
{
uint8 i;
for(i=0;i<8;i++)
{
dq=0;
dq=dat&0x01;
dat>>=1;
delay(8);//Only this block has the most accurate timing requirement, its time must be greater than 15us
dq=1;
delay(1);
}
}
uint8 ds18b20rd() //18b20 read data
{
uint8 value,i;
for(i=0;i<8;i++)
{
dq=0;
value>>=1;
dq=1;
if(dq==1)value|=0x80;
delay(8);//In this section, the time requirement is also very accurate, the whole program must be greater than 60us
}
return value;
}
uint8 readtemp() //Read the temperature that needs to be reset
{
uint8 b;
ds18b20init(); //Initialize
ds18b20wr(0xcc); //Send the ignore ROM command
ds18b20wr(0x44); //Send the temperature conversion command
delay(100);
ds18b20init(); //Initialize
ds18b20wr(0xcc); //Send the ignore ROM command
ds18b20wr(0xbe); //Send the read register command
a=ds18b20rd(); //The low eight bits of temperature
b=ds18b20rd(); //The high eight bits of temperature
b<<=4; //ssss s***; s is the flag s=0 means the temperature is positive, s=1 means the temperature is negative
c=b&0x80; //Confirm the positive and negative flag of temperature
b+=(a&0xf0)>>4;
a=a&0x0f; //Decimal part of temperature
return b;
}

void key_pros() //Key processing function
{
if(k1==0)
{
delay(1000);
if(k1==0)
{
mode++;
if(mode==5)mode=0;
wrc(0x01);
}
while(!k1);
}
if(mode==1) //Set the upper limit of temperature
{
if(k2==0) //Add
{
delay(1000);
if(k2==0)
{
temph++;
if(temph>=80)temph=80;
}
while(!k2);
}
if(k3==0) //Subtract
{
delay(1000);
if(k3==0)
{
temph--;
if(temph<=0)temph=0;
}
while(!k3);
}
}
if(mode==2) //Set the lower limit of temperature
{
if(k2==0) //Add
{
delay(1000);
if(k2==0)
{
templ++;
if(templ>=80)templ=80;
}
while(!k2);
}
if(k3==0) //Subtract
{
delay(1000);
if(k3==0)
{
templ--;
if(templ<=0)templ=0;
}
while(!k3);
}
}
if(mode==3) //Set the upper limit of humidity
{
if(k2==0) //Add
{
delay(1000);
if(k2==0)
{
humih++;
if(humih>=80)humih=80;
}
while(!k2);
}
if(k3==0) //Subtract
{
delay(1000);
if(k3==0)
{
humih--;
if(humih<=0)humih=0;
}
while(!k3);
}
}
if(mode==4) //Set the lower limit of humidity
{
if(k2==0) //Add
{
delay(1000);
if(k2==0)
{
humil++;
if(humil>=80)humil=80;
}
while(!k2);
}
if(k3==0) //减
{
delay(1000);
if(k3==0)
{
humil--;
if(humil<=0)humil=0;
}
while(!k3);
}
}
}

void lcd_init_display() //LCD initialization display
{
uint8 i;
for(i=0;i<5;i++)
{
wrc(0x80+i);
wrd(str1);
}

for(i=0;i<5;i++)
{
wrc(0xc0+i);
wrd(str2);
}
}

void data_pros() //data processing function
{
uint8 i;
uint8 temp_buf[2],humi_buf[2];
uint8 temphbuf[2],templbuf[2],humihbuf[2],humilbuf[2];
float dio;
uint16 k;

tempvalue=readtemp();
DHT11_Read_Data(&temp,&humi);
temp_buf[0]=temp/10+0x30;
temp_buf[1]=temp%10+0x30;

humi_buf[0]=humi/10+0x30;
humi_buf[1]=humi%10+0x30;

dio=a*0.0625;
k=dio*10000; // take the two significant digits after the decimal point

temphbuf[0]=temph/10+0x30;
tempbuf[1]=temph%10+0x30;
templbuf[0]=templ/10+0x30;
templbuf[1]=templ%10+0x30;

humihbuf[0]=humih/10+0x30;
humihbuf[1]=humih%10+0x30;
humblebuf[0]=humble/10+0x30;
humblebuf[1]=humble%10+0x30;

if(mode==0)
{
lcd_init_display();
wrc(0x85);
wrd(num[tempvalue%100/10]);
wrd(num[tempvalue%100%10]);
wrd('.');
wrd( num[k/1000]);
wrd(0xdf);
wrd('C');

for(i=0;i<2;i++)
{
wrc(0Xc5+i);
wrd(humi_buf);
}
for (i=0;i<3;i++)
{
wrc(0Xc7+i);
wrd(str5);
}
}
if(mode==1) //The upper limit of temperature display
{
wrc(0x80);
for(i =0;i<6;i++)
{
wrd(str6);
}
wrd(temphbuf[0]);
wrd(temphbuf[1]);
}
if(mode==2) //Temperature lower limit display
{
wrc(0x80);
for(i=0;i<6;i++)
{
wrd(str7);
}
wrd(templbuf[0]);
wrd(templbuf[1]);
}
if(mode==3) //Humidity upper limit display
{
wrc(0x80);
for(i=0;i<6;i++)
{
wrd(str8);
}
wrd(humihbuf[0]);
wrd( humihbuf[1]);
}
if(mode==4) //humidity lower limit display
{
wrc(0x80);
for(i=0;i<6;i++)
{
wrd(str9);
}
wrd(humilbuf [0]);
wrd(humilbuf[1]);
}
}

void baojinpros() //Alarm processing
{
if(tempvalue>=temph||humi>=humih) //The detected temperature or humidity is higher than the set upper limit, cooling and humidity
{
led1=1; //The cooling and humidity indicator
led2=0;
}
if(tempvalue<=templ||humi<=humil) //The detected temperature or humidity is lower than the set lower limit, heating and humidity
{
led1=0;
led2=1; //Increasing the temperature and humidity indicator
}
if((tempvalue>templ&&tempvalue<temph)&&(humi>humil&&humi<humih))
{
led1=0;
led2=0;
}
}

void main()
{
uint8 i=0;
led1=0;
led2=0;
lcd_init();
while(DHT11_Init()) //Check if DHT11 is pure in
{
for(i=0;i<5;i++)
{
wrc(0x80+i);
wrd(str3);
}
}
wrc(0x01);
lcd_init_display(); //LCD initialization displayi
=0;
while(1)
{
i++;
key_pros();
baojinpros(); //Alarm processingif
(i==15)
{
i=0;
data_pros(); //Reading DHT11 data once must be at least greater than 100ms
}
delay(1000);

}
}

annysky2012

Good, keep it up. It would be best if you could show it in person.