功能介绍：
0.本系统采用STC89C52作为单片机
1.LCD1602液晶实时显示当前车位状态
2.当超声波探头检测到距离小于500mm时，判断为当前车位有车，否则无车
3.超声波传感器型号采用HC-SR04
4.预留4个功能按键和蓝牙通信模块可自行开发新的功能
5.电源接口采用DC002直接输入5V供电
原理图：
PCB：
主程序：
#include <reg52.h>#include <intrins.h>#include <stdio.h>#include "delay.h"#include "lcd1602.h"#define OFF 1#define ON 0sbit TRIG_1 = P1^0; //接口定义sbit ECHO_1 = P1^1; //接口定义sbit LED_VOID_1 = P1^2;sbit LED_PARKING_1 = P1^3;sbit TRIG_2 = P2^0; //接口定义sbit ECHO_2 = P2^1; //接口定义sbit LED_VOID_2 = P1^4;sbit LED_PARKING_2 = P1^5;sbit TRIG_3 = P2^4; //接口定义sbit ECHO_3 = P2^5; //接口定义sbit LED_VOID_3 = P2^3;sbit LED_PARKING_3 = P2^2;xdata unsigned char dis0[16]; //定义显示区域临时存储数组xdata unsigned char dis1[16];bit disFlag = 0; //显示标志bit refreshFlag = 0; //显示标志unsigned char i;unsigned char occupiedFlag1 = 0; //位置标志unsigned char occupiedFlag2 = 0; //位置标志unsigned char occupiedFlag3 = 0; //位置标志unsigned char occupiedNum = 0;//占用总数float f_distance1 = 0; //距离1float f_distance2 = 0; //距离2float f_distance3 = 0; //距离3void Timer1_Init(void); //函数声明void Measuring(void);//void UART_SendStr(unsigned char *s, unsigned char length);//void UART_Init(void);//void UART_SendByte(unsigned char dat);void main(void){TRIG_1 = 0;TRIG_2 = 0;TRIG_3 = 0;TMOD &= 0xF0;//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 = 0; //重新赋值 20msTL0 = 0;EA = 1; //总中断打开Timer1_Init(); //定时器0初始化LCD_Init(); //初始化液晶DelayMs(20); //延时有助于稳定LCD_Clear(); //清屏while (1){if (refreshFlag == 1){refreshFlag = 0;Measuring();}if (disFlag == 1) //定时显示{disFlag = 0; //标志位清零if (f_distance1 <= 500) //检测到车距0.5m{occupiedFlag1 = 1;} //标志else{occupiedFlag1 = 0;}if (f_distance2 <= 500) //检测到车距0.5m{occupiedFlag2 = 1;} //标志else{occupiedFlag2 = 0;}if (f_distance3 <= 500) //检测到车距0.5m{occupiedFlag3 = 1;} //标志else{occupiedFlag3 = 0;}if (occupiedFlag1 == 1){LCD_DispStr(0, 1, "P ");LED_VOID_1 = OFF;LED_PARKING_1 = ON;} //显示占用else{LCD_DispStr(0, 1, "N ");LED_VOID_1 = ON;LED_PARKING_1 = OFF;}if (occupiedFlag2 == 1){LCD_DispStr(2, 1, "P ");LED_VOID_2 = OFF;LED_PARKING_2 = ON;} //显示占用else{LCD_DispStr(2, 1, "N ");LED_VOID_2 = ON;LED_PARKING_2 = OFF;}if (occupiedFlag3 == 1){LCD_DispStr(4, 1, "P ");LED_VOID_3 = OFF;LED_PARKING_3 = ON;} //显示占用else{LCD_DispStr(4, 1, "N ");LED_VOID_3 = ON;LED_PARKING_3 = OFF;}occupiedNum = occupiedFlag1 + occupiedFlag2 + occupiedFlag3; //占用总数sprintf(dis0, "1 2 3 P:%d N:%d ", (int)occupiedNum, (int)(3 - occupiedNum)); //打印LCD_DispStr(0, 0, dis0); //显示 //显示}}}void Measuring(void){static long cnt = 0; //定时器计数TR1 = 0;TRIG_1 = 1; //启动一次模块//不可以使用其他终端 容易造成死循环DelayUs10x(1);TRIG_1 = 0;while (!ECHO_1); //当RX为零时等待TR0 = 1; //开启计数while (ECHO_1); //当RX为1计数并等待TR0 = 0;cnt = (long)(TH0 * 256 + TL0);TH0 = 0;TL0 = 0;f_distance1 = (float)cnt * 17 / 100.0 * 1.102; //算出来是mm (g_cnt * 340 / 2) / 1000.0 * 1.102;系数cnt = 0;TRIG_2 = 1; //启动一次模块//不可以使用其他终端 容易造成死循环DelayUs10x(1);TRIG_2 = 0;while (!ECHO_2); //当RX为零时等待TR0 = 1; //开启计数while (ECHO_2); //当RX为1计数并等待TR0 = 0;cnt = (long)(TH0 * 256 + TL0);TH0 = 0;TL0 = 0;f_distance2 = (float)cnt * 17 / 100.0 * 1.102; //算出来是mm (g_cnt * 340 / 2) / 1000.0 * 1.102;系数cnt = 0;TRIG_3 = 1; //启动一次模块//不可以使用其他终端 容易造成死循环DelayUs10x(1);TRIG_3 = 0;while (!ECHO_3); //当RX为零时等待TR0 = 1; //开启计数while (ECHO_3); //当RX为1计数并等待TR0 = 0;cnt = (long)(TH0 * 256 + TL0);TH0 = 0;TL0 = 0;f_distance3 = (float)cnt * 17 / 100.0 * 1.102; //算出来是mm (g_cnt * 340 / 2) / 1000.0 * 1.102;系数cnt = 0;TR1 = 1;}void Timer1_Init(void){TMOD |= 0x10;//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TMOD &= 0x0F;//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TH1 = (65536 - 18432) / 256; //重新赋值 20msTL1 = (65536 - 18432) % 256;EA = 1; //总中断打开ET1 = 1; //定时器中断打开TR1 = 1; //定时器开关打开}void Timer1_Interrupt(void) interrupt 3{static unsigned int time_20ms = 0;TH1 = (65536 - 18432) / 256; //重新赋值 20msTL1 = (65536 - 18432) % 256;time_20ms++;if (time_20ms >= 25){disFlag = 1;time_20ms = 0;}else{time_20ms++;}if (time_20ms % 5 == 0){refreshFlag = 1;}}
仿真演示视频：
/video/BV15B4y197mW/
实物演示视频：
/video/BV1vt4y1W7cM/
