51单片机DHT11和LCD1602的温湿度显示设计

51单片机DHT11和LCD1602的温湿度显示设计可以通过以下步骤实现：

1. 连接DHT11传感器和LCD1602显示屏到51单片机。

2. 编写51单片机程序，包括读取DHT11传感器的温湿度数据、将数据转换为字符串、显示温湿度数据在LCD1602显示屏上。

3. 调试程序，确保程序能够正常运行。

4. 实施电路和程序，并测试。

以下是一个简单的代码示例：

#include <reg52.h>
#include <stdio.h>

/* LCD1602 */
#define LCD_RS P2_6
#define LCD_RW P2_5
#define LCD_EN P2_7
#define LCD_DATA P0

/* DHT11 */
#define DHT11_DATA P1_0

/* 延时 */
void delay(unsigned int t)
{
while (t--);
}

/* 向LCD写入命令 */
void lcd_write_command(unsigned char command)
{
LCD_RS = 0;
LCD_RW = 0;
LCD_DATA = command;
LCD_EN = 1;
delay(10);
LCD_EN = 0;
}

/* 向LCD写入数据 */
void lcd_write_data(unsigned char data)
{
LCD_RS = 1;
LCD_RW = 0;
LCD_DATA = data;
LCD_EN = 1;
delay(10);
LCD_EN = 0;
}

/* 初始化LCD */
void lcd_init()
{
lcd_write_command(0x38);
lcd_write_command(0x0c);
lcd_write_command(0x06);
lcd_write_command(0x01);
}

/* 显示字符串 */
void lcd_write_string(unsigned char *s)
{
while (*s)
{
lcd_write_data(*s);
s++;
}
}

/* 读取DHT11数据 */
void dht11_read_data(unsigned char *humidity, unsigned char *temperature)
{
unsigned char data[5] = {0};
unsigned char i;

/* 主机发送起始信号 */
DHT11_DATA = 0;
delay(18000);
DHT11_DATA = 1;
delay(40);

/* 等待DHT11响应 */
if (DHT11_DATA == 0)
{
while (!DHT11_DATA);
while (DHT11_DATA);
/* 接收数据 */
for (i = 0; i < 5; i++)
{
unsigned char j;
for (j = 0; j < 8; j++)
{
while (!DHT11_DATA);
delay(30);
data[i] <<= 1;
if (DHT11_DATA == 1)
{
data[i] |= 0x01;
}
while (DHT11_DATA);
}
}
/* 验证数据 */
if ((data[0] + data[1] + data[2] + data[3]) == data[4])
{
*humidity = data[0];
*temperature = data[2];
}
}
}

/* 将数值转换为字符串 */
void itoa(unsigned char *str, unsigned char num)
{
sprintf(str, "%d", num);
}

/* 主函数 */
void main()
{
unsigned char humidity, temperature;
unsigned char str1[4], str2[4];

/* 初始化LCD */
lcd_init();

while (1)
{
/* 读取温湿度数据 */
dht11_read_data(&humidity, &temperature);

/* 显示温湿度数据 */
lcd_write_command(0x80);
lcd_write_string("Humidity:");
itoa(str1, humidity);
lcd_write_string(str1);
lcd_write_string("%");

lcd_write_command(0xc0);
lcd_write_string("Temperature:");
itoa(str2, temperature);
lcd_write_string(str2);
lcd_write_string("C");

/* 延时1秒 */
delay(50000);
delay(50000);
}
}