Temperature and humidity monitoring + timing alarm system based on 51 single chip microcomputer (C51 source code)

Functional specifications ：
1.DS1302 Module real-time display time （ The display time can be initialized through the program ）
2.DHT11 Temperature and humidity measurement
3. Press the key to set the timing alarm time , And store the set value in 24C02 in （ After power failure, the previous setting data can be restored ）
4.LCD1602 Display relevant information

matters needing attention ：

processor ：STC89C51/STC89C52

display ：LCD1602

ROM Storage ：24C02

Time to show ：DS1302

Temperature and humidity measurement ：DHT11

Press the key to adjust the alarm time

Chinese notes of relevant pin connection

//--- Definition lcd1602 The use of IO mouth ---//
#define LCD_DATA P0
sbit RS=P2^7;
sbit RW=P2^6;
sbit EN=P2^5;
//--- Definition   Key   The use of IO mouth ---//
sbit key1=P1^5; 
sbit key2=P1^6; 
sbit key3=P1^7;
//--- Definition ds1302 The use of IO mouth ---//
sbit SCLK=P1^2;
sbit DSIO=P1^3;
sbit RST=P1^4;
//---DS1302 Address commands for writing and reading hours, minutes and seconds ---//
//--- Second minute hour Sun Moon anniversary   Lowest read / write bit ;-------//
uchar code READ_RTC_ADDR[7] = {
    0x81, 0x83, 0x85, 0x87, 0x89, 0x8b, 0x8d}; 
uchar code WRITE_RTC_ADDR[7] = {
    0x80, 0x82, 0x84, 0x86, 0x88, 0x8a, 0x8c};
//--- DS1302 Clock initialization 2021 year 3 month 8 Japan 16 spot 46 branch 00 second  ---//
//---  second   branch   when   Japan   month   Zhou   year  ---//
uchar TIME[7] = {
    0, 0x46, 0x16, 0x08, 0x03, 0x01, 0x21};
uchar warn_hour,real_hour;// Alarm time , By reading the flash obtain 
//--- Definition  dh11  The use of IO mouth ---//
sbit dat=P2^2;
uchar DHT11[5],RTflag=0;
uchar FLAG; 
//--- Definition  2402  The use of IO mouth ---//
sbit SDA=P1^1;
sbit SCL=P1^0;
//--- Definition  beep  The use of IO mouth ---//
sbit beep=P2^0;
uchar beep_state=1;
//--- Definition  led  The use of IO mouth ---//
sbit led=P2^1;

Main function code

void 
main()
{
    
    lcd_init(); 										//1602 initialization 
	init_2402();										//2402 initialization 
	warn_hour =read_data(0);							// read out 24c02 The saved value is assigned to the alarm time 
// Ds1302Init(); // Turn on when time needs to be set , By default, there is no need to set the time 
    while(1)											// Cyclic reading   And update the data display 
    {
    
		Ds1302ReadTime();	   							// Read time 
		LcdDisplay();									// Display time 
  		key_scan();	  									// Scan button 
        DHT11_5(); 										// Reading data 
		dis_str(12,0,"H:");dis_shu(14,0,warn_hour);		// Display alarm time 
	    dis_str(9,1,"S");dis_shu(10,1,DHT11[0]);		// humidity 
	    dis_str(13,1,"T");dis_shu(14,1,DHT11[2]);		// temperature 
		warn();											// Call the police 
    }
}

See the comments section for links to all the information , Please leave a message if you have any questions ~
author ：amusen
Time ：2022.4
I wish good ！