51 MCU OLED+dht11 source program to display temperature

I have been learning 51 MCU for more than a month, and stayed up all night to write the OLED+DHT11 program for a competition.

The microcontroller source program is as follows:

#include "REG51.h"

#include "oled.h"

#include

typedef unsigned char BYTE;

typedef unsigned int WORD;

#define uint unsigned int

#define uchar unsigned char

sbit io=P1^2; //dht11data is connected to the P1^0 port of the microcontroller //

sbit IN1 = P1^0;                        

sbit IN2 = P1^1; //Input motor interface

sbit K1 = P3^0;

sbit K2 = P3^1; //button interface

uchar data_byte;

uchar RH,RL,TH,TL;

int count1,a;

void DelayUs2x(unsigned char t)

{

        while(--t);

}

void DelayMs(unsigned char t)

{

        while(t--)

        {

//About 1mS delay

        DelayUs2x(245);

        DelayUs2x(245);

        }

}

void delay(uchar ms) //delay module//

{

  uchar i;

  while(ms--)                 

for(i=0;i<100;i++);

}

void delay1() //A for loop takes about 8 machine cycles. One machine cycle is 1us, and the crystal oscillator is 12MHz. This means that this function delays more than 8us. This delay function must be a little more precise.

{

  uchar i;

  for(i=0;i<1;i++);

}

//Motor program

void ZHUAN(){

          IN2=0;

   }

void speed(int cnt,int sd)

{  

if(cnt        {

        IN1=1;

        }

else  

        {

        IN1=0;

        }

}  

void turn(int cnt,int sd)                                   

{  

    ZHUAN();          

        speed(cnt,sd);

}  

void start()//start signal

{

  io=1;

  delay1();

  io=0;

  delay(25); // The host must pull the bus low for more than 18ms to ensure that DHT11 can detect the start signal

  io=1; //After sending the start signal, pull the level high and delay for 20-40us

  delay1(); //The following three delay functions are about 24us, which meets the requirements

  delay1();

  delay1();

}

uchar receive_byte() //Receive a byte //

{

  uchar i,temp;

  for(i=0;i<8;i++) //Receive 8-bit data

  {

        while(!io); //Wait for 50us low level start signal to end

        delay1(); //After the start signal ends, delay 26us-28us, the following three delay functions

         delay1();

        delay1();

        temp=0; //The time is 26us-28us, indicating that the received data is '0'

        if(io==1)

         temp=1; //If it is still high level after 26us-28us, it means the received data is '1'

    while(io); //Wait for data signal high level (26us-28us for '0' and 70us for '1')

        data_byte<<=1; //The received data has the high bit first and is shifted right

         data_byte|=temp;

  }

  return data_byte;

}

void receive()//Receive data//

{

  uchar T_H,T_L,R_H,R_L,check,num_check,i;

  start(); //Start signal//

  io=1; // Host is set as input to judge the response signal of slave DHT11

  if(!io)//Judge whether the slave has a low level response signal//

  {  

        while(!io); //Judge whether the slave has finished sending out the 80us low-level response signal //

        while(io); //Judge whether the slave has finished sending out a high level of 80us. If so, the host enters the data receiving state.

        R_H=receive_byte(); //High humidity

        R_L=receive_byte(); // Humidity low bit

        T_H=receive_byte(); // high temperature

        T_L=receive_byte(); // low temperature

        check=receive_byte(); //check bit

        io=0; //After the last bit of data is received, the slave device pulls the level down for 50us//

        for(i=0;i<7;i++)//About 50us delay

        delay1();

        io=1; //The bus is pulled high by the pull-up resistor and enters the idle state

        num_check=R_H+R_L+T_H+T_L;

        if(num_check==check)//Judge whether the sum of the four data read is the same as the check bit

        {

   RH=R_H;

   RL=R_L;

   TH=T_H;

   TL=T_L;

   check=num_check;

        }

  }

}

int main(void)

{       

        TMOD=0x01;

        EA=1;  

        TH0=(65536-1000)/256;

        TL0=(65536-1000)%256;

        ET0=1;

        TR0=1;

        a = 100;

                OLED_Init(); //Initialize OLED  

                OLED_Clear();

                OLED_ShowCHinese(36,0,0);

                OLED_ShowCHinese(54,0,1);

                OLED_ShowCHinese(72,0,2);

                OLED_ShowCHinese(0,2,3);

                OLED_ShowCHinese(18,2,5);

                OLED_ShowCHinese(0,4,4);

                OLED_ShowCHinese(18,4,5);

                OLED_ShowString(37,4,":",16);

                  OLED_ShowString(37,2,":",16);

        while(1)

        {

            turn(count1,a);

                if(K1==0)

                {

                        DelayMs(100);

                        if(K1==0)// debounce

                        {

                           if(a>=0)

                           a=a-10;

                        }

                        }

                if(K2==0)

……………………