功能介绍：
0.本系统采用STC89C52作为单片机
1.LCD1602液晶实时显示当前温度和设定温度
2.当温度到达100℃时，蜂鸣器报警提醒水烧开了
3.按键可更改预设温度值，当温度低于设定温度5℃时，
启动加热，直至加热到设定值，停止加热，启动保温的作用
原理图：
PCB：
主程序：
#include <reg52.h> //包含头文件，一般情况不需要改动，头文件包含特殊功能寄存器的定义#include <stdio.h>#include "18b20.h"#include "lcd1602.h"#include "delay.h"sbit KEY_SET = P3^3; //引脚定义sbit KEY_SUB = P3^6;sbit KEY_ADD = P3^4;sbit KEY_SWITCH = P3^5;sbit RELAY_WATER = P2^0;sbit RELAY_HEAT = P2^1;sbit BUZZER = P2^2;sbit WATER_CHECK = P1^1;#define ON 0#define OFF 1int waterTime = 0; //加水时间int tempBuf = 0; //读取温度值float temperature; //实际温度值float setTemp = 100.0; //预设温度bit refreshFlag = 0; //定义读温度标志bit heatSwitch = OFF; //加热开关char dis0[16]; //定义显示区域临时存储数组void CheckKey(void);void Timer0_Init(void); //定时器初始化void main(void){bit ack = 0;Timer0_Init();LCD_Init(); //初始化液晶DelayMs(200); //延时有助于稳定LCD_Clear(); //清屏while (1) //主循环{if (refreshFlag == 1) //1s刷新一次数据{refreshFlag = 0;//TR0 = 0;if (WATER_CHECK == 0) //检测到没有水{DelayMs(20); //防抖if (WATER_CHECK == 0) //确定没有水了{waterTime = 60; //加水60sheatSwitch = OFF; //关闭加热开关}}if (waterTime != 0){waterTime--;RELAY_WATER = ON; //加水}else{RELAY_WATER = OFF;}DS18B20_Start();ack = DS18B20_GetTemp(&tempBuf); //检测温度if (ack == 1){temperature = (float)tempBuf * 0.0625; //温度值转换}else {temperature = 0;}if (heatSwitch == ON) //加热开关打开{if (temperature < setTemp - 5) //低于设定温度5℃，启动加热{RELAY_HEAT = ON;}else if (temperature >= setTemp) //直接大于等于设定温度，停止加热{RELAY_HEAT = OFF;}if (temperature >= 100) //温度达到100℃，蜂鸣器报警{BUZZER = ON;}else{BUZZER = OFF;}}else //加热开关关闭{RELAY_HEAT = OFF;BUZZER = OFF;}sprintf(dis0, "Set Temp:%5.1f", setTemp); //打印温度值LCD_DispStr(0, 0, dis0); //显示LCD_DispOneChar(14, 0, 0xdf); //写入温度右上角点LCD_DispOneChar(15, 0, 'C'); //写入温度Csprintf(dis0, "Temp:%5.1f", temperature); //打印温度值LCD_DispStr(0, 1, dis0); //显示LCD_DispOneChar(10, 1, 0xdf); //写入温度右上角点LCD_DispOneChar(11, 1, 'C'); //写入温度Cif (heatSwitch == ON) //显示加热开关{sprintf(dis0, " ON", temperature); //打印温度值LCD_DispStr(12, 1, dis0); //显示}else{sprintf(dis0, " OFF", temperature); //打印温度值LCD_DispStr(12, 1, dis0); //显示}//TR0 = 1;}CheckKey(); //检测按键}}void CheckKey(void){if (KEY_SWITCH == 0) //检测到按键按下{DelayMs(10); //小抖动if (KEY_SWITCH == 0) //开关按键{heatSwitch = ~heatSwitch; //加热开关控制}while (KEY_SWITCH == 0);}if (KEY_SUB == 0) //减值键{DelayMs(200); if (KEY_SUB == 0) //减值键{setTemp--;if (setTemp < 20){setTemp = 100;}sprintf(dis0, "Set Temp:%5.1f", setTemp); //打印温度值LCD_DispStr(0, 0, dis0); //显示}}if (KEY_ADD == 0) //加值键{DelayMs(200); if (KEY_ADD == 0) //减值键{setTemp++;if (setTemp > 100){setTemp = 20;}sprintf(dis0, "Set Temp:%5.1f", setTemp); //打印温度值LCD_DispStr(0, 0, dis0); //显示}}}/*------------------------------------------------定时器初始化子程序------------------------------------------------*/void Timer0_Init(void){TMOD |= 0x01; //使用模式1，16位定时器，使用"|"符号可以在使用多个定时器时不受影响TH0 = (65536 - 18432) / 256; //重新赋值 20msTL0 = (65536 - 18432) % 256;EA = 1; //总中断打开ET0 = 1; //定时器中断打开TR0 = 1; //定时器开关打开}/*------------------------------------------------定时器中断子程序------------------------------------------------*/void Timer0_Interrupt(void) interrupt 1{static unsigned char time20ms = 0;TH0 = (65536 - 18432) / 256; //重新赋值 20msTL0 = (65536 - 18432) % 256;time20ms++;if (time20ms > 50){time20ms = 0;refreshFlag = 1; //读标志位置1}}
仿真演示视频：
/video/BV1Yr4y147N8/
实物演示视频：
/video/BV1Kr4y147cm/
