DHT11实验演示单总线理论

Tutorial: 电子电路 Category: 嵌入式 Published: 2026-08-29 08:09:36 Views: 0 Likes: 0 Comments: 0

072.10.1 DHT11实验演示单总线理论

/* ==================== Delay\delay.c ==================== */
#include "delay.h"
#include <intrins.h>

void Delay_xms(uint xms)	//@11.0592MHz
{
	uchar data i, j;
	while(xms)
	{
		_nop_();
		i = 2;
		j = 199;
		do
		{
			while (--j);
		} while (--i);
    xms--;		
	}
}

void Delay5us(void)	//@11.0592MHz
{
}

void Delay30us(void)	//@11.0592MHz
{
	unsigned char data i;

	i = 11;
	while (--i);
}


/* ==================== Delay\delay.h ==================== */
#ifndef _DELAY_H_
#define _DELAY_H_
#include "main.h"

void Delay_xms(uint xms);
void Delay5us(void);
void Delay30us(void);
#endif

/* ==================== DHT11\dht11.c ==================== */
#include "dht11.h"
#include "delay.h"
#include "main.h"
#include <intrins.h>

unsigned char DHT11_Start(void)
{
	unsigned char count = 0;
	DHT_IO = 1;
	Delay30us();
	DHT_IO = 0;
	Delay_xms(20); //拉低20ms,主机发送开始信号
	DHT_IO = 1;	
	Delay30us();
	while(!DHT_IO && count<80)
	{
		_nop_();
		count++;
	}
	if(count >= 80) //超时,返回值为1,代表通信失败
		return 1;
	count = 0;
	while(DHT_IO && count<80)
	{
		_nop_();
		count++;
	}
	if(count >= 80)
		return 1; //超时,返回值为1,代表通信失败
	return 0;
}

unsigned char DHT11_Read(unsigned char *humi, unsigned char *temp)
{
	unsigned char dht11_data[5] = {0};
	unsigned char x,y,data_bit,data_byte,count = 0;
	if(1 == DHT11_Start())
		return 1; //超时,返回值为1,代表通信失败
	for(x=0; x<5; x++)
	{
		for(y=0; y<8; y++)
		{
			while(!DHT_IO && count<80)
			{
				_nop_();
				count++;
			}
			if(count >= 80)
				return 1; //超时,返回值为1,代表通信失败
			count = 0;
			Delay30us();
			if(DHT_IO == 1)
			{
				data_bit = 1; 
				while(DHT_IO&& count<80)
				{
					_nop_();
					count++;
				}
				if(count >= 80)
				 return 1; //超时,返回值为1,代表通信失败
			}
			else
			{
				data_bit = 0;
			}
			data_byte = data_byte << 1; //移位,其实for的第一次不需要移位,不过没影响
			data_byte |= data_bit; //把数据给到data_byte的最低位,然后通过移位往前移动
		}
		dht11_data[x] = data_byte; //每个字节的数据给到数组
	}
	
	if(dht11_data[0] + dht11_data[1] + dht11_data[2] + dht11_data[3] == dht11_data[4])//校验和
	{
		*humi = dht11_data[0]; //指针地址解引用,赋值
		*temp = dht11_data[2];
	}
	else
	{
		return 1; //校验和不对,返回值为1,代表通信失败
	}
	return 0;
}

/* ==================== DHT11\dht11.h ==================== */
#ifndef _DHT11_H_
#define _DHT11_H_

unsigned char DHT11_Start(void);
unsigned char DHT11_Read(unsigned char *humi, unsigned char *temp);

#endif


/* ==================== IIC\iic.c ==================== */
#include "iic.h"
#include "main.h"
#include "delay.h"

void IIC_Start(void)
{
	IIC_SCL = 1;
	IIC_SDA = 1;
	Delay5us();
	IIC_SDA = 0;
	Delay5us();
	IIC_SCL = 0;
}

void IIC_Stop(void)
{
	IIC_SCL = 1;
	IIC_SDA = 0;
	Delay5us();
	IIC_SDA = 1;
}

void IIC_Send_Byte(unsigned char IIC_Byte)
{
	char i;
	for(i = 0; i<8; i++)
	{		
		IIC_SDA = IIC_Byte & (0x80 >> i);
		IIC_SCL = 1;
		Delay5us();
		IIC_SCL = 0;
		Delay5us();		
	}
}

unsigned char IIC_Recv_Ack(void)
{
	unsigned char ack;
	IIC_SDA = 1;
	IIC_SCL = 1;
	Delay5us();
	ack = IIC_SDA;
	IIC_SCL = 0;
	Delay5us();	
	
	return ack;
}

/* ==================== IIC\iic.h ==================== */
#ifndef _IIC_H_
#define _IIC_H_

void IIC_Start(void);
void IIC_Stop(void);
void IIC_Send_Byte(unsigned char IIC_Byte);
unsigned char IIC_Recv_Ack(void);

#endif



/* ==================== main.c ==================== */
#include "reg52.h"
#include <intrins.h>
#include "delay.h"
#include "main.h"
#include "uart.h"
#include "oled.h"
#include "dht11.h"
#include <stdio.h>

uchar humity,temperature;
uchar data_buf[10] = {0};
uint time_count = 0;
void main()
{
//	UART_Init();
	OLED_Init();			//初始化OLED  
	OLED_Clear();

	OLED_ShowCHinese(0,0,0); //温湿度检测系统
	OLED_ShowCHinese(18,0,1);
	OLED_ShowCHinese(36,0,2);
	OLED_ShowCHinese(54,0,3);
	OLED_ShowCHinese(72,0,4);
	OLED_ShowCHinese(90,0,5);
	OLED_ShowCHinese(108,0,6);	

	while(1)
  {
		if(time_count == 0)  //每隔1秒读取一次数据,手册要求
		{
			if(0 == DHT11_Read(&humity, &temperature))
			{
				sprintf(data_buf,"H:%u%% T:%uC ", (uint)humity, (uint)temperature);
				OLED_ShowString(0,4,data_buf,16);	//显示数据
			}
			else
			{
				sprintf(data_buf,"DHT11 Error");
				OLED_ShowString(0,4,data_buf,16);	//显示错误		
			}	
		}
		time_count++;
		time_count = time_count%1000;
		Delay_xms(1);	
  }
}


/* ==================== main.h ==================== */
#ifndef _MAIN_H_
#define _MAIN_H_

#include "reg52.h"

typedef unsigned char uchar;
typedef unsigned int uint;

extern uchar recv;

sbit LED1 = P1^0;
sbit LED2 = P1^1;
sbit LED3 = P1^2;
sbit LED4 = P1^3;
sbit BEEP = P1^6;
sbit JDQ1 = P2^0;

sbit IIC_SCL = P1^5;
sbit IIC_SDA = P1^4;

sbit DHT_IO = P1^2;

#endif



/* ==================== OLED\oled.c ==================== */
#include "oled.h"
#include "oledfont.h"  	 
#include "iic.h"

//OLED的显存
//存放格式如下.
//[0]0 1 2 3 ... 127	
//[1]0 1 2 3 ... 127	
//[2]0 1 2 3 ... 127	
//[3]0 1 2 3 ... 127	
//[4]0 1 2 3 ... 127	
//[5]0 1 2 3 ... 127	
//[6]0 1 2 3 ... 127	
//[7]0 1 2 3 ... 127 			   
void delay_ms(unsigned int ms)
{                         
	unsigned int a;
	while(ms)
	{
		a=1800;
		while(a--);
		ms--;
	}
	return;
}
/**********************************************
//IIC Start
**********************************************/
//void IIC_Start()
//{
//	OLED_SCLK_Set() ;
//	OLED_SDIN_Set();
//	OLED_SDIN_Clr();
//	OLED_SCLK_Clr();
//}

/**********************************************
//IIC Stop
**********************************************/
//void IIC_Stop()
//{
//  OLED_SCLK_Set() ;
//  //OLED_SCLK_Clr();
//	OLED_SDIN_Clr();
//	OLED_SDIN_Set();
//	
//}

//void IIC_Wait_Ack()
//{
//	OLED_SCLK_Set() ;
//	OLED_SCLK_Clr();
//}
/**********************************************
// IIC Write byte
**********************************************/

//void Write_IIC_Byte(unsigned char IIC_Byte)
//{
//	unsigned char i;
//	unsigned char m,da;
//	da=IIC_Byte;
//	OLED_SCLK_Clr();
//	for(i=0;i<8;i++)		
//	{
//		m=da;
//		//	OLED_SCLK_Clr();
//		m=m&0x80;
//		if(m==0x80)
//		{OLED_SDIN_Set();}
//		else OLED_SDIN_Clr();
//			da=da<<1;
//		OLED_SCLK_Set();
//		OLED_SCLK_Clr();
//	}
//}
/**********************************************
// IIC Write Command
**********************************************/
void Write_IIC_Command(unsigned char IIC_Command)
{
	IIC_Start();
	IIC_Send_Byte(0x78);      //Slave address,SA0=0
	IIC_Recv_Ack();	
	IIC_Send_Byte(0x00);			//write command
	IIC_Recv_Ack();	
	IIC_Send_Byte(IIC_Command); 
	IIC_Recv_Ack();	
	IIC_Stop();
}
/**********************************************
// IIC Write Data
**********************************************/
void Write_IIC_Data(unsigned char IIC_Data)
{
	IIC_Start();
	IIC_Send_Byte(0x78);			//D/C#=0; R/W#=0
	IIC_Recv_Ack();	
	IIC_Send_Byte(0x40);			//write data
	IIC_Recv_Ack();	
	IIC_Send_Byte(IIC_Data);
	IIC_Recv_Ack();	
	IIC_Stop();
}

void OLED_WR_Byte(unsigned dat,unsigned cmd)
{
	if(cmd)
	{
    Write_IIC_Data(dat);  
	}
	else
	{
    Write_IIC_Command(dat);		
	}
}

/********************************************
// fill_Picture
********************************************/
void fill_picture(unsigned char fill_Data)
{
	unsigned char m,n;
	for(m=0;m<8;m++)
	{
		OLED_WR_Byte(0xb0+m,0);		//page0-page1
		OLED_WR_Byte(0x00,0);		//low column start address
		OLED_WR_Byte(0x10,0);		//high column start address
		for(n=0;n<128;n++)
		{
			OLED_WR_Byte(fill_Data,1);
		}
	}
}


/***********************Delay****************************************/
void Delay_50ms(unsigned int Del_50ms)
{
	unsigned int m;
	for(;Del_50ms>0;Del_50ms--)
		for(m=6245;m>0;m--);
}

void Delay_1ms(unsigned int Del_1ms)
{
	unsigned char j;
	while(Del_1ms--)
	{	
		for(j=0;j<123;j++);
	}
}

//坐标设置
	void OLED_Set_Pos(unsigned char x, unsigned char y) 
{ 
	OLED_WR_Byte(0xb0+y,OLED_CMD);
	OLED_WR_Byte(((x&0xf0)>>4)|0x10,OLED_CMD);
	OLED_WR_Byte((x&0x0f),OLED_CMD); 
}   	  
//开启OLED显示    
void OLED_Display_On(void)
{
	OLED_WR_Byte(0X8D,OLED_CMD);  //SET DCDC命令
	OLED_WR_Byte(0X14,OLED_CMD);  //DCDC ON
	OLED_WR_Byte(0XAF,OLED_CMD);  //DISPLAY ON
}
//关闭OLED显示     
void OLED_Display_Off(void)
{
	OLED_WR_Byte(0X8D,OLED_CMD);  //SET DCDC命令
	OLED_WR_Byte(0X10,OLED_CMD);  //DCDC OFF
	OLED_WR_Byte(0XAE,OLED_CMD);  //DISPLAY OFF
}		   			 
//清屏函数,清完屏,整个屏幕是黑色的!和没点亮一样!!!	  
void OLED_Clear(void)  
{  
	u8 i,n;		    
	for(i=0;i<8;i++)  
	{  
		OLED_WR_Byte (0xb0+i,OLED_CMD);    //设置页地址(0~7)
		OLED_WR_Byte (0x00,OLED_CMD);      //设置显示位置—列低地址
		OLED_WR_Byte (0x10,OLED_CMD);      //设置显示位置—列高地址   
		for(n=0;n<128;n++)
		  OLED_WR_Byte(0,OLED_DATA); 
	} //更新显示
}
void OLED_On(void)  
{  
	u8 i,n;		    
	for(i=0;i<8;i++)  
	{  
		OLED_WR_Byte (0xb0+i,OLED_CMD);    //设置页地址(0~7)
		OLED_WR_Byte (0x00,OLED_CMD);      //设置显示位置—列低地址
		OLED_WR_Byte (0x10,OLED_CMD);      //设置显示位置—列高地址   
		for(n=0;n<128;n++)
		 OLED_WR_Byte(1,OLED_DATA); 
	} //更新显示
}
//在指定位置显示一个字符,包括部分字符
//x:0~127
//y:0~63
//mode:0,反白显示;1,正常显示				 
//size:选择字体 16/12 
void OLED_ShowChar(u8 x,u8 y,u8 chr,u8 Char_Size)
{      	
	unsigned char c=0,i=0;	
	c=chr-' ';//得到偏移后的值			
	if(x>Max_Column-1)
	{
		x=0;
		y=y+2;
	}
	if(Char_Size ==16)
	{
		OLED_Set_Pos(x,y);	
		for(i=0;i<8;i++)
		OLED_WR_Byte(F8X16[c*16+i],OLED_DATA);
		OLED_Set_Pos(x,y+1);
		for(i=0;i<8;i++)
		OLED_WR_Byte(F8X16[c*16+i+8],OLED_DATA);
	}
	else 
	{	
		OLED_Set_Pos(x,y);
		for(i=0;i<6;i++)
		OLED_WR_Byte(F6x8[c][i],OLED_DATA);			
	}
}
//m^n函数
u32 oled_pow(u8 m,u8 n)
{
	u32 result=1;	 
	while(n--)
	{
	  result*=m;
	}    
	return result;
}				  
//显示2个数字
//x,y :起点坐标	 
//len :数字的位数
//size:字体大小
//mode:模式	0,填充模式;1,叠加模式
//num:数值(0~4294967295);	 		  
void OLED_ShowNum(u8 x,u8 y,u32 num,u8 len,u8 size2)
{         	
	u8 t,temp;
	u8 enshow=0;						   
	for(t=0;t<len;t++)
	{
		temp=(num/oled_pow(10,len-t-1))%10;
		if(enshow==0&&t<(len-1))
		{
			if(temp==0)
			{
				OLED_ShowChar(x+(size2/2)*t,y,' ',size2);
				continue;
			}
			else 
				enshow=1; 		 	 
		}
	 	OLED_ShowChar(x+(size2/2)*t,y,temp+'0',size2); 
	}
} 
//显示一个字符号串
void OLED_ShowString(u8 x,u8 y,u8 *chr,u8 Char_Size)
{
	unsigned char j=0;
	while (chr[j]!='\0')
	{		
		OLED_ShowChar(x,y,chr[j],Char_Size);
		x+=8;
		if(x>120){x=0;y+=2;}
		 j++;
	}
}
//显示汉字
void OLED_ShowCHinese(u8 x,u8 y,u8 no)
{      			    
	u8 t,adder=0;
	OLED_Set_Pos(x,y);	
	for(t=0;t<16;t++)
	{
		OLED_WR_Byte(Hzk[2*no][t],OLED_DATA);
		adder+=1;
	}	
	OLED_Set_Pos(x,y+1);	
	for(t=0;t<16;t++)
	{	
		OLED_WR_Byte(Hzk[2*no+1][t],OLED_DATA);
		adder+=1;
	}					
}
/***********功能描述:显示显示BMP图片128×64起始点坐标(x,y),x的范围0~127,y为页的范围0~7*****************/
void OLED_DrawBMP(unsigned char x0, unsigned char y0,unsigned char x1, unsigned char y1,unsigned char BMP[])
{ 	
 unsigned int j=0;
 unsigned char x,y;
  
  if(y1%8==0)
		y=y1/8;      
  else 
		y=y1/8+1;
	for(y=y0;y<y1;y++)
	{
		OLED_Set_Pos(x0,y);
    for(x=x0;x<x1;x++)
	  {      
	    OLED_WR_Byte(BMP[j++],OLED_DATA);	    	
	  }
	}
} 

//初始化SSD1306					    
void OLED_Init(void)
{ 	
 
	OLED_WR_Byte(0xAE,OLED_CMD);//--display off
	OLED_WR_Byte(0x00,OLED_CMD);//---set low column address
	OLED_WR_Byte(0x10,OLED_CMD);//---set high column address
	OLED_WR_Byte(0x40,OLED_CMD);//--set start line address  
	OLED_WR_Byte(0xB0,OLED_CMD);//--set page address
	OLED_WR_Byte(0x81,OLED_CMD); // contract control
	OLED_WR_Byte(0xFF,OLED_CMD);//--128   
	OLED_WR_Byte(0xA1,OLED_CMD);//set segment remap 
	OLED_WR_Byte(0xA6,OLED_CMD);//--normal / reverse
	OLED_WR_Byte(0xA8,OLED_CMD);//--set multiplex ratio(1 to 64)
	OLED_WR_Byte(0x3F,OLED_CMD);//--1/32 duty
	OLED_WR_Byte(0xC8,OLED_CMD);//Com scan direction
	OLED_WR_Byte(0xD3,OLED_CMD);//-set display offset
	OLED_WR_Byte(0x00,OLED_CMD);//
	
	OLED_WR_Byte(0xD5,OLED_CMD);//set osc division
	OLED_WR_Byte(0x80,OLED_CMD);//
	
	OLED_WR_Byte(0xD8,OLED_CMD);//set area color mode off
	OLED_WR_Byte(0x05,OLED_CMD);//
	
	OLED_WR_Byte(0xD9,OLED_CMD);//Set Pre-Charge Period
	OLED_WR_Byte(0xF1,OLED_CMD);//
	
	OLED_WR_Byte(0xDA,OLED_CMD);//set com pin configuartion
	OLED_WR_Byte(0x12,OLED_CMD);//
	
	OLED_WR_Byte(0xDB,OLED_CMD);//set Vcomh
	OLED_WR_Byte(0x30,OLED_CMD);//
	
	OLED_WR_Byte(0x8D,OLED_CMD);//set charge pump enable
	OLED_WR_Byte(0x14,OLED_CMD);//
	
	OLED_WR_Byte(0xAF,OLED_CMD);//--turn on oled panel
}  































/* ==================== OLED\oled.h ==================== */
//#include "REG51.h"
#ifndef __OLED_H
#define __OLED_H			  	 
//#include "sys.h"
//#include "stdlib.h"	  
#define  u8 unsigned char 
#define  u32 unsigned int 
#define OLED_CMD  0	//写命令
#define OLED_DATA 1	//写数据
#define OLED_MODE 0

//sbit OLED_SCL=P1^5;//时钟 D0(SCLK?
//sbit OLED_SDIN=P1^4;//D1(MOSI) 数据

//#define OLED_SCLK_Clr() OLED_SCL=0
//#define OLED_SCLK_Set() OLED_SCL=1

//#define OLED_SDIN_Clr() OLED_SDIN=0
//#define OLED_SDIN_Set() OLED_SDIN=1





//OLED模式设置
//0:4线串行模式
//1:并行8080模式

#define SIZE 16
#define XLevelL		0x02
#define XLevelH		0x10
#define Max_Column	128
#define Max_Row		64
#define	Brightness	0xFF 
#define X_WIDTH 	128
#define Y_WIDTH 	64	    						  
//-----------------OLED端口定义----------------  					   

void delay_ms(unsigned int ms);

//OLED控制用函数
void OLED_WR_Byte(unsigned dat,unsigned cmd);  
void OLED_Display_On(void);
void OLED_Display_Off(void);	   							   		    
void OLED_Init(void);
void OLED_Clear(void);
void OLED_DrawPoint(u8 x,u8 y,u8 t);
void OLED_Fill(u8 x1,u8 y1,u8 x2,u8 y2,u8 dot);
void OLED_ShowChar(u8 x,u8 y,u8 chr,u8 Char_Size);
void OLED_ShowNum(u8 x,u8 y,u32 num,u8 len,u8 size);
void OLED_ShowString(u8 x,u8 y, u8 *p,u8 Char_Size);	 
void OLED_Set_Pos(unsigned char x, unsigned char y);
void OLED_ShowCHinese(u8 x,u8 y,u8 no);
void OLED_DrawBMP(unsigned char x0, unsigned char y0,unsigned char x1, unsigned char y1,unsigned char BMP[]);
void Delay_50ms(unsigned int Del_50ms);
void Delay_1ms(unsigned int Del_1ms);
void fill_picture(unsigned char fill_Data);
void Picture();
void IIC_Start();
void IIC_Stop();
void Write_IIC_Command(unsigned char IIC_Command);
void Write_IIC_Data(unsigned char IIC_Data);
void Write_IIC_Byte(unsigned char IIC_Byte);
void IIC_Wait_Ack();

#endif  
	 





/* ==================== OLED\oledfont.h ==================== */
#ifndef __OLEDFONT_H
#define __OLEDFONT_H 	   
//常用ASCII表
//偏移量32
//ASCII字符集
//偏移量32
//大小:12*6
/************************************6*8的点阵************************************/
const unsigned char code F6x8[][6] =		
{
0x00, 0x00, 0x00, 0x00, 0x00, 0x00,// sp
0x00, 0x00, 0x00, 0x2f, 0x00, 0x00,// !
0x00, 0x00, 0x07, 0x00, 0x07, 0x00,// "
0x00, 0x14, 0x7f, 0x14, 0x7f, 0x14,// #
0x00, 0x24, 0x2a, 0x7f, 0x2a, 0x12,// $
0x00, 0x62, 0x64, 0x08, 0x13, 0x23,// %
0x00, 0x36, 0x49, 0x55, 0x22, 0x50,// &
0x00, 0x00, 0x05, 0x03, 0x00, 0x00,// '
0x00, 0x00, 0x1c, 0x22, 0x41, 0x00,// (
0x00, 0x00, 0x41, 0x22, 0x1c, 0x00,// )
0x00, 0x14, 0x08, 0x3E, 0x08, 0x14,// *
0x00, 0x08, 0x08, 0x3E, 0x08, 0x08,// +
0x00, 0x00, 0x00, 0xA0, 0x60, 0x00,// ,
0x00, 0x08, 0x08, 0x08, 0x08, 0x08,// -
0x00, 0x00, 0x60, 0x60, 0x00, 0x00,// .
0x00, 0x20, 0x10, 0x08, 0x04, 0x02,// /
0x00, 0x3E, 0x51, 0x49, 0x45, 0x3E,// 0
0x00, 0x00, 0x42, 0x7F, 0x40, 0x00,// 1
0x00, 0x42, 0x61, 0x51, 0x49, 0x46,// 2
0x00, 0x21, 0x41, 0x45, 0x4B, 0x31,// 3
0x00, 0x18, 0x14, 0x12, 0x7F, 0x10,// 4
0x00, 0x27, 0x45, 0x45, 0x45, 0x39,// 5
0x00, 0x3C, 0x4A, 0x49, 0x49, 0x30,// 6
0x00, 0x01, 0x71, 0x09, 0x05, 0x03,// 7
0x00, 0x36, 0x49, 0x49, 0x49, 0x36,// 8
0x00, 0x06, 0x49, 0x49, 0x29, 0x1E,// 9
0x00, 0x00, 0x36, 0x36, 0x00, 0x00,// :
0x00, 0x00, 0x56, 0x36, 0x00, 0x00,// ;
0x00, 0x08, 0x14, 0x22, 0x41, 0x00,// <
0x00, 0x14, 0x14, 0x14, 0x14, 0x14,// =
0x00, 0x00, 0x41, 0x22, 0x14, 0x08,// >
0x00, 0x02, 0x01, 0x51, 0x09, 0x06,// ?
0x00, 0x32, 0x49, 0x59, 0x51, 0x3E,// @
0x00, 0x7C, 0x12, 0x11, 0x12, 0x7C,// A
0x00, 0x7F, 0x49, 0x49, 0x49, 0x36,// B
0x00, 0x3E, 0x41, 0x41, 0x41, 0x22,// C
0x00, 0x7F, 0x41, 0x41, 0x22, 0x1C,// D
0x00, 0x7F, 0x49, 0x49, 0x49, 0x41,// E
0x00, 0x7F, 0x09, 0x09, 0x09, 0x01,// F
0x00, 0x3E, 0x41, 0x49, 0x49, 0x7A,// G
0x00, 0x7F, 0x08, 0x08, 0x08, 0x7F,// H
0x00, 0x00, 0x41, 0x7F, 0x41, 0x00,// I
0x00, 0x20, 0x40, 0x41, 0x3F, 0x01,// J
0x00, 0x7F, 0x08, 0x14, 0x22, 0x41,// K
0x00, 0x7F, 0x40, 0x40, 0x40, 0x40,// L
0x00, 0x7F, 0x02, 0x0C, 0x02, 0x7F,// M
0x00, 0x7F, 0x04, 0x08, 0x10, 0x7F,// N
0x00, 0x3E, 0x41, 0x41, 0x41, 0x3E,// O
0x00, 0x7F, 0x09, 0x09, 0x09, 0x06,// P
0x00, 0x3E, 0x41, 0x51, 0x21, 0x5E,// Q
0x00, 0x7F, 0x09, 0x19, 0x29, 0x46,// R
0x00, 0x46, 0x49, 0x49, 0x49, 0x31,// S
0x00, 0x01, 0x01, 0x7F, 0x01, 0x01,// T
0x00, 0x3F, 0x40, 0x40, 0x40, 0x3F,// U
0x00, 0x1F, 0x20, 0x40, 0x20, 0x1F,// V
0x00, 0x3F, 0x40, 0x38, 0x40, 0x3F,// W
0x00, 0x63, 0x14, 0x08, 0x14, 0x63,// X
0x00, 0x07, 0x08, 0x70, 0x08, 0x07,// Y
0x00, 0x61, 0x51, 0x49, 0x45, 0x43,// Z
0x00, 0x00, 0x7F, 0x41, 0x41, 0x00,// [
0x00, 0x55, 0x2A, 0x55, 0x2A, 0x55,// 55
0x00, 0x00, 0x41, 0x41, 0x7F, 0x00,// ]
0x00, 0x04, 0x02, 0x01, 0x02, 0x04,// ^
0x00, 0x40, 0x40, 0x40, 0x40, 0x40,// _
0x00, 0x00, 0x01, 0x02, 0x04, 0x00,// '
0x00, 0x20, 0x54, 0x54, 0x54, 0x78,// a
0x00, 0x7F, 0x48, 0x44, 0x44, 0x38,// b
0x00, 0x38, 0x44, 0x44, 0x44, 0x20,// c
0x00, 0x38, 0x44, 0x44, 0x48, 0x7F,// d
0x00, 0x38, 0x54, 0x54, 0x54, 0x18,// e
0x00, 0x08, 0x7E, 0x09, 0x01, 0x02,// f
0x00, 0x18, 0xA4, 0xA4, 0xA4, 0x7C,// g
0x00, 0x7F, 0x08, 0x04, 0x04, 0x78,// h
0x00, 0x00, 0x44, 0x7D, 0x40, 0x00,// i
0x00, 0x40, 0x80, 0x84, 0x7D, 0x00,// j
0x00, 0x7F, 0x10, 0x28, 0x44, 0x00,// k
0x00, 0x00, 0x41, 0x7F, 0x40, 0x00,// l
0x00, 0x7C, 0x04, 0x18, 0x04, 0x78,// m
0x00, 0x7C, 0x08, 0x04, 0x04, 0x78,// n
0x00, 0x38, 0x44, 0x44, 0x44, 0x38,// o
0x00, 0xFC, 0x24, 0x24, 0x24, 0x18,// p
0x00, 0x18, 0x24, 0x24, 0x18, 0xFC,// q
0x00, 0x7C, 0x08, 0x04, 0x04, 0x08,// r
0x00, 0x48, 0x54, 0x54, 0x54, 0x20,// s
0x00, 0x04, 0x3F, 0x44, 0x40, 0x20,// t
0x00, 0x3C, 0x40, 0x40, 0x20, 0x7C,// u
0x00, 0x1C, 0x20, 0x40, 0x20, 0x1C,// v
0x00, 0x3C, 0x40, 0x30, 0x40, 0x3C,// w
0x00, 0x44, 0x28, 0x10, 0x28, 0x44,// x
0x00, 0x1C, 0xA0, 0xA0, 0xA0, 0x7C,// y
0x00, 0x44, 0x64, 0x54, 0x4C, 0x44,// z
0x14, 0x14, 0x14, 0x14, 0x14, 0x14,// horiz lines
};
/****************************************8*16的点阵************************************/
const unsigned char code F8X16[]=	  
{
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,// 0
  0x00,0x00,0x00,0xF8,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x33,0x30,0x00,0x00,0x00,//! 1
  0x00,0x10,0x0C,0x06,0x10,0x0C,0x06,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,//" 2
  0x40,0xC0,0x78,0x40,0xC0,0x78,0x40,0x00,0x04,0x3F,0x04,0x04,0x3F,0x04,0x04,0x00,//# 3
  0x00,0x70,0x88,0xFC,0x08,0x30,0x00,0x00,0x00,0x18,0x20,0xFF,0x21,0x1E,0x00,0x00,//$ 4
  0xF0,0x08,0xF0,0x00,0xE0,0x18,0x00,0x00,0x00,0x21,0x1C,0x03,0x1E,0x21,0x1E,0x00,//% 5
  0x00,0xF0,0x08,0x88,0x70,0x00,0x00,0x00,0x1E,0x21,0x23,0x24,0x19,0x27,0x21,0x10,//& 6
  0x10,0x16,0x0E,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,//' 7
  0x00,0x00,0x00,0xE0,0x18,0x04,0x02,0x00,0x00,0x00,0x00,0x07,0x18,0x20,0x40,0x00,//( 8
  0x00,0x02,0x04,0x18,0xE0,0x00,0x00,0x00,0x00,0x40,0x20,0x18,0x07,0x00,0x00,0x00,//) 9
  0x40,0x40,0x80,0xF0,0x80,0x40,0x40,0x00,0x02,0x02,0x01,0x0F,0x01,0x02,0x02,0x00,//* 10
  0x00,0x00,0x00,0xF0,0x00,0x00,0x00,0x00,0x01,0x01,0x01,0x1F,0x01,0x01,0x01,0x00,//+ 11
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0xB0,0x70,0x00,0x00,0x00,0x00,0x00,//, 12
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x01,0x01,0x01,0x01,0x01,0x01,//- 13
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x30,0x30,0x00,0x00,0x00,0x00,0x00,//. 14
  0x00,0x00,0x00,0x00,0x80,0x60,0x18,0x04,0x00,0x60,0x18,0x06,0x01,0x00,0x00,0x00,/// 15
  0x00,0xE0,0x10,0x08,0x08,0x10,0xE0,0x00,0x00,0x0F,0x10,0x20,0x20,0x10,0x0F,0x00,//0 16
  0x00,0x10,0x10,0xF8,0x00,0x00,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00,//1 17
  0x00,0x70,0x08,0x08,0x08,0x88,0x70,0x00,0x00,0x30,0x28,0x24,0x22,0x21,0x30,0x00,//2 18
  0x00,0x30,0x08,0x88,0x88,0x48,0x30,0x00,0x00,0x18,0x20,0x20,0x20,0x11,0x0E,0x00,//3 19
  0x00,0x00,0xC0,0x20,0x10,0xF8,0x00,0x00,0x00,0x07,0x04,0x24,0x24,0x3F,0x24,0x00,//4 20
  0x00,0xF8,0x08,0x88,0x88,0x08,0x08,0x00,0x00,0x19,0x21,0x20,0x20,0x11,0x0E,0x00,//5 21
  0x00,0xE0,0x10,0x88,0x88,0x18,0x00,0x00,0x00,0x0F,0x11,0x20,0x20,0x11,0x0E,0x00,//6 22
  0x00,0x38,0x08,0x08,0xC8,0x38,0x08,0x00,0x00,0x00,0x00,0x3F,0x00,0x00,0x00,0x00,//7 23
  0x00,0x70,0x88,0x08,0x08,0x88,0x70,0x00,0x00,0x1C,0x22,0x21,0x21,0x22,0x1C,0x00,//8 24
  0x00,0xE0,0x10,0x08,0x08,0x10,0xE0,0x00,0x00,0x00,0x31,0x22,0x22,0x11,0x0F,0x00,//9 25
  0x00,0x00,0x00,0xC0,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x30,0x30,0x00,0x00,0x00,//: 26
  0x00,0x00,0x00,0x80,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x60,0x00,0x00,0x00,0x00,//; 27
  0x00,0x00,0x80,0x40,0x20,0x10,0x08,0x00,0x00,0x01,0x02,0x04,0x08,0x10,0x20,0x00,//< 28
  0x40,0x40,0x40,0x40,0x40,0x40,0x40,0x00,0x04,0x04,0x04,0x04,0x04,0x04,0x04,0x00,//= 29
  0x00,0x08,0x10,0x20,0x40,0x80,0x00,0x00,0x00,0x20,0x10,0x08,0x04,0x02,0x01,0x00,//> 30
  0x00,0x70,0x48,0x08,0x08,0x08,0xF0,0x00,0x00,0x00,0x00,0x30,0x36,0x01,0x00,0x00,//? 31
  0xC0,0x30,0xC8,0x28,0xE8,0x10,0xE0,0x00,0x07,0x18,0x27,0x24,0x23,0x14,0x0B,0x00,//@ 32
  0x00,0x00,0xC0,0x38,0xE0,0x00,0x00,0x00,0x20,0x3C,0x23,0x02,0x02,0x27,0x38,0x20,//A 33
  0x08,0xF8,0x88,0x88,0x88,0x70,0x00,0x00,0x20,0x3F,0x20,0x20,0x20,0x11,0x0E,0x00,//B 34
  0xC0,0x30,0x08,0x08,0x08,0x08,0x38,0x00,0x07,0x18,0x20,0x20,0x20,0x10,0x08,0x00,//C 35
  0x08,0xF8,0x08,0x08,0x08,0x10,0xE0,0x00,0x20,0x3F,0x20,0x20,0x20,0x10,0x0F,0x00,//D 36
  0x08,0xF8,0x88,0x88,0xE8,0x08,0x10,0x00,0x20,0x3F,0x20,0x20,0x23,0x20,0x18,0x00,//E 37
  0x08,0xF8,0x88,0x88,0xE8,0x08,0x10,0x00,0x20,0x3F,0x20,0x00,0x03,0x00,0x00,0x00,//F 38
  0xC0,0x30,0x08,0x08,0x08,0x38,0x00,0x00,0x07,0x18,0x20,0x20,0x22,0x1E,0x02,0x00,//G 39
  0x08,0xF8,0x08,0x00,0x00,0x08,0xF8,0x08,0x20,0x3F,0x21,0x01,0x01,0x21,0x3F,0x20,//H 40
  0x00,0x08,0x08,0xF8,0x08,0x08,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00,//I 41
  0x00,0x00,0x08,0x08,0xF8,0x08,0x08,0x00,0xC0,0x80,0x80,0x80,0x7F,0x00,0x00,0x00,//J 42
  0x08,0xF8,0x88,0xC0,0x28,0x18,0x08,0x00,0x20,0x3F,0x20,0x01,0x26,0x38,0x20,0x00,//K 43
  0x08,0xF8,0x08,0x00,0x00,0x00,0x00,0x00,0x20,0x3F,0x20,0x20,0x20,0x20,0x30,0x00,//L 44
  0x08,0xF8,0xF8,0x00,0xF8,0xF8,0x08,0x00,0x20,0x3F,0x00,0x3F,0x00,0x3F,0x20,0x00,//M 45
  0x08,0xF8,0x30,0xC0,0x00,0x08,0xF8,0x08,0x20,0x3F,0x20,0x00,0x07,0x18,0x3F,0x00,//N 46
  0xE0,0x10,0x08,0x08,0x08,0x10,0xE0,0x00,0x0F,0x10,0x20,0x20,0x20,0x10,0x0F,0x00,//O 47
  0x08,0xF8,0x08,0x08,0x08,0x08,0xF0,0x00,0x20,0x3F,0x21,0x01,0x01,0x01,0x00,0x00,//P 48
  0xE0,0x10,0x08,0x08,0x08,0x10,0xE0,0x00,0x0F,0x18,0x24,0x24,0x38,0x50,0x4F,0x00,//Q 49
  0x08,0xF8,0x88,0x88,0x88,0x88,0x70,0x00,0x20,0x3F,0x20,0x00,0x03,0x0C,0x30,0x20,//R 50
  0x00,0x70,0x88,0x08,0x08,0x08,0x38,0x00,0x00,0x38,0x20,0x21,0x21,0x22,0x1C,0x00,//S 51
  0x18,0x08,0x08,0xF8,0x08,0x08,0x18,0x00,0x00,0x00,0x20,0x3F,0x20,0x00,0x00,0x00,//T 52
  0x08,0xF8,0x08,0x00,0x00,0x08,0xF8,0x08,0x00,0x1F,0x20,0x20,0x20,0x20,0x1F,0x00,//U 53
  0x08,0x78,0x88,0x00,0x00,0xC8,0x38,0x08,0x00,0x00,0x07,0x38,0x0E,0x01,0x00,0x00,//V 54
  0xF8,0x08,0x00,0xF8,0x00,0x08,0xF8,0x00,0x03,0x3C,0x07,0x00,0x07,0x3C,0x03,0x00,//W 55
  0x08,0x18,0x68,0x80,0x80,0x68,0x18,0x08,0x20,0x30,0x2C,0x03,0x03,0x2C,0x30,0x20,//X 56
  0x08,0x38,0xC8,0x00,0xC8,0x38,0x08,0x00,0x00,0x00,0x20,0x3F,0x20,0x00,0x00,0x00,//Y 57
  0x10,0x08,0x08,0x08,0xC8,0x38,0x08,0x00,0x20,0x38,0x26,0x21,0x20,0x20,0x18,0x00,//Z 58
  0x00,0x00,0x00,0xFE,0x02,0x02,0x02,0x00,0x00,0x00,0x00,0x7F,0x40,0x40,0x40,0x00,//[ 59
  0x00,0x0C,0x30,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x06,0x38,0xC0,0x00,//\ 60
  0x00,0x02,0x02,0x02,0xFE,0x00,0x00,0x00,0x00,0x40,0x40,0x40,0x7F,0x00,0x00,0x00,//] 61
  0x00,0x00,0x04,0x02,0x02,0x02,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,//^ 62
  0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x80,//_ 63
  0x00,0x02,0x02,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,//` 64
  0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x00,0x19,0x24,0x22,0x22,0x22,0x3F,0x20,//a 65
  0x08,0xF8,0x00,0x80,0x80,0x00,0x00,0x00,0x00,0x3F,0x11,0x20,0x20,0x11,0x0E,0x00,//b 66
  0x00,0x00,0x00,0x80,0x80,0x80,0x00,0x00,0x00,0x0E,0x11,0x20,0x20,0x20,0x11,0x00,//c 67
  0x00,0x00,0x00,0x80,0x80,0x88,0xF8,0x00,0x00,0x0E,0x11,0x20,0x20,0x10,0x3F,0x20,//d 68
  0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x00,0x1F,0x22,0x22,0x22,0x22,0x13,0x00,//e 69
  0x00,0x80,0x80,0xF0,0x88,0x88,0x88,0x18,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00,//f 70
  0x00,0x00,0x80,0x80,0x80,0x80,0x80,0x00,0x00,0x6B,0x94,0x94,0x94,0x93,0x60,0x00,//g 71
  0x08,0xF8,0x00,0x80,0x80,0x80,0x00,0x00,0x20,0x3F,0x21,0x00,0x00,0x20,0x3F,0x20,//h 72
  0x00,0x80,0x98,0x98,0x00,0x00,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00,//i 73
  0x00,0x00,0x00,0x80,0x98,0x98,0x00,0x00,0x00,0xC0,0x80,0x80,0x80,0x7F,0x00,0x00,//j 74
  0x08,0xF8,0x00,0x00,0x80,0x80,0x80,0x00,0x20,0x3F,0x24,0x02,0x2D,0x30,0x20,0x00,//k 75
  0x00,0x08,0x08,0xF8,0x00,0x00,0x00,0x00,0x00,0x20,0x20,0x3F,0x20,0x20,0x00,0x00,//l 76
  0x80,0x80,0x80,0x80,0x80,0x80,0x80,0x00,0x20,0x3F,0x20,0x00,0x3F,0x20,0x00,0x3F,//m 77
  0x80,0x80,0x00,0x80,0x80,0x80,0x00,0x00,0x20,0x3F,0x21,0x00,0x00,0x20,0x3F,0x20,//n 78
  0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x00,0x1F,0x20,0x20,0x20,0x20,0x1F,0x00,//o 79
  0x80,0x80,0x00,0x80,0x80,0x00,0x00,0x00,0x80,0xFF,0xA1,0x20,0x20,0x11,0x0E,0x00,//p 80
  0x00,0x00,0x00,0x80,0x80,0x80,0x80,0x00,0x00,0x0E,0x11,0x20,0x20,0xA0,0xFF,0x80,//q 81
  0x80,0x80,0x80,0x00,0x80,0x80,0x80,0x00,0x20,0x20,0x3F,0x21,0x20,0x00,0x01,0x00,//r 82
  0x00,0x00,0x80,0x80,0x80,0x80,0x80,0x00,0x00,0x33,0x24,0x24,0x24,0x24,0x19,0x00,//s 83
  0x00,0x80,0x80,0xE0,0x80,0x80,0x00,0x00,0x00,0x00,0x00,0x1F,0x20,0x20,0x00,0x00,//t 84
  0x80,0x80,0x00,0x00,0x00,0x80,0x80,0x00,0x00,0x1F,0x20,0x20,0x20,0x10,0x3F,0x20,//u 85
  0x80,0x80,0x80,0x00,0x00,0x80,0x80,0x80,0x00,0x01,0x0E,0x30,0x08,0x06,0x01,0x00,//v 86
  0x80,0x80,0x00,0x80,0x00,0x80,0x80,0x80,0x0F,0x30,0x0C,0x03,0x0C,0x30,0x0F,0x00,//w 87
  0x00,0x80,0x80,0x00,0x80,0x80,0x80,0x00,0x00,0x20,0x31,0x2E,0x0E,0x31,0x20,0x00,//x 88
  0x80,0x80,0x80,0x00,0x00,0x80,0x80,0x80,0x80,0x81,0x8E,0x70,0x18,0x06,0x01,0x00,//y 89
  0x00,0x80,0x80,0x80,0x80,0x80,0x80,0x00,0x00,0x21,0x30,0x2C,0x22,0x21,0x30,0x00,//z 90
  0x00,0x00,0x00,0x00,0x80,0x7C,0x02,0x02,0x00,0x00,0x00,0x00,0x00,0x3F,0x40,0x40,//{ 91
  0x00,0x00,0x00,0x00,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xFF,0x00,0x00,0x00,//| 92
  0x00,0x02,0x02,0x7C,0x80,0x00,0x00,0x00,0x00,0x40,0x40,0x3F,0x00,0x00,0x00,0x00,//} 93
  0x00,0x06,0x01,0x01,0x02,0x02,0x04,0x04,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,//~ 94
};
unsigned char code Hzk[][32]={

//{0x00,0x00,0xF0,0x10,0x10,0x10,0x10,0xFF,0x10,0x10,0x10,0x10,0xF0,0x00,0x00,0x00},
//{0x00,0x00,0x0F,0x04,0x04,0x04,0x04,0xFF,0x04,0x04,0x04,0x04,0x0F,0x00,0x00,0x00},/*"中",0*/

//{0x40,0x40,0x40,0x5F,0x55,0x55,0x55,0x75,0x55,0x55,0x55,0x5F,0x40,0x40,0x40,0x00},
//{0x00,0x40,0x20,0x0F,0x09,0x49,0x89,0x79,0x09,0x09,0x09,0x0F,0x20,0x40,0x00,0x00},/*"景",1*/

//{0x00,0xFE,0x02,0x42,0x4A,0xCA,0x4A,0x4A,0xCA,0x4A,0x4A,0x42,0x02,0xFE,0x00,0x00},
//{0x00,0xFF,0x40,0x50,0x4C,0x43,0x40,0x40,0x4F,0x50,0x50,0x5C,0x40,0xFF,0x00,0x00},/*"园",2*/

//{0x00,0x00,0xF8,0x88,0x88,0x88,0x88,0xFF,0x88,0x88,0x88,0x88,0xF8,0x00,0x00,0x00},
//{0x00,0x00,0x1F,0x08,0x08,0x08,0x08,0x7F,0x88,0x88,0x88,0x88,0x9F,0x80,0xF0,0x00},/*"电",3*/

//{0x80,0x82,0x82,0x82,0x82,0x82,0x82,0xE2,0xA2,0x92,0x8A,0x86,0x82,0x80,0x80,0x00},
//{0x00,0x00,0x00,0x00,0x00,0x40,0x80,0x7F,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00},/*"子",4*/

//{0x24,0x24,0xA4,0xFE,0xA3,0x22,0x00,0x22,0xCC,0x00,0x00,0xFF,0x00,0x00,0x00,0x00},
//{0x08,0x06,0x01,0xFF,0x00,0x01,0x04,0x04,0x04,0x04,0x04,0xFF,0x02,0x02,0x02,0x00},/*"科",5*/

//{0x10,0x10,0x10,0xFF,0x10,0x90,0x08,0x88,0x88,0x88,0xFF,0x88,0x88,0x88,0x08,0x00},
//{0x04,0x44,0x82,0x7F,0x01,0x80,0x80,0x40,0x43,0x2C,0x10,0x28,0x46,0x81,0x80,0x00},/*"技",6*/


// 温(0) 湿(1) 度(2) 检(3) 测(4) 系(5) 统(6)

{0x10,0x60,0x02,0x8C,0x00,0x00,0xFE,0x92,0x92,0x92,0x92,0x92,0xFE,0x00,0x00,0x00},
{0x04,0x04,0x7E,0x01,0x40,0x7E,0x42,0x42,0x7E,0x42,0x7E,0x42,0x42,0x7E,0x40,0x00},/*"温",0*/
/* (16 X 16 , 宋体 )*/

{0x10,0x60,0x02,0x8C,0x00,0xFE,0x92,0x92,0x92,0x92,0x92,0x92,0xFE,0x00,0x00,0x00},
{0x04,0x04,0x7E,0x01,0x44,0x48,0x50,0x7F,0x40,0x40,0x7F,0x50,0x48,0x44,0x40,0x00},/*"湿",1*/
/* (16 X 16 , 宋体 )*/

{0x00,0x00,0xFC,0x24,0x24,0x24,0xFC,0x25,0x26,0x24,0xFC,0x24,0x24,0x24,0x04,0x00},
{0x40,0x30,0x8F,0x80,0x84,0x4C,0x55,0x25,0x25,0x25,0x55,0x4C,0x80,0x80,0x80,0x00},/*"度",2*/
/* (16 X 16 , 宋体 )*/

{0x10,0x10,0xD0,0xFF,0x90,0x50,0x20,0x50,0x4C,0x43,0x4C,0x50,0x20,0x40,0x40,0x00},
{0x04,0x03,0x00,0xFF,0x00,0x41,0x44,0x58,0x41,0x4E,0x60,0x58,0x47,0x40,0x40,0x00},/*"检",3*/
/* (16 X 16 , 宋体 )*/

{0x10,0x60,0x02,0x8C,0x00,0xFE,0x02,0xF2,0x02,0xFE,0x00,0xF8,0x00,0xFF,0x00,0x00},
{0x04,0x04,0x7E,0x01,0x80,0x47,0x30,0x0F,0x10,0x27,0x00,0x47,0x80,0x7F,0x00,0x00},/*"测",4*/
/* (16 X 16 , 宋体 )*/

{0x00,0x00,0x22,0x32,0x2A,0xA6,0xA2,0x62,0x21,0x11,0x09,0x81,0x01,0x00,0x00,0x00},
{0x00,0x42,0x22,0x13,0x0B,0x42,0x82,0x7E,0x02,0x02,0x0A,0x12,0x23,0x46,0x00,0x00},/*"系",5*/
/* (16 X 16 , 宋体 )*/

{0x20,0x30,0xAC,0x63,0x30,0x00,0x88,0xC8,0xA8,0x99,0x8E,0x88,0xA8,0xC8,0x88,0x00},
{0x22,0x67,0x22,0x12,0x12,0x80,0x40,0x30,0x0F,0x00,0x00,0x3F,0x40,0x40,0x71,0x00},/*"统",6*/
/* (16 X 16 , 宋体 )*/

};

#endif




/* ==================== Uart\uart.c ==================== */
#include "uart.h"
#include "main.h"

//串口发送一个字节
void UART_Send_Byte(uchar send_byte)
{
	SBUF = send_byte;
	while(!TI);
	TI=0;
}

//串口发送字符串
void UART_Send_Str(uchar *send_str)
{	
	while(*send_str != '\0') //判断字符串结束符,如果识别到‘\0',则跳出while,结束发送
	{
		UART_Send_Byte(*send_str++);	//本质是一个字节一个字节的发送,
		//发送完一个字节,地址+1,等待发送下一个字节,直到检测到字符串结束符为止
	}	
} 

void UART_Init(void)
{
	SCON = 0x50; 	//串口配成工作方式1
	PCON &= 0x7F; //波特率不加倍
	TMOD &= 0x0f;	
	TMOD |= 0x20;	//定时器1,模式二,自动重装初值,串口按照一定速率发数据,需要用的定时器
	TH1 = 0xFD;	
	TL1 = 0xFD; //@11.0592MH时钟,9600比特率定时器初值
	TR1 = 1; //定时器开始运行   
	ES = 1;  //串口中断打开
	EA=1;					//总中断打开
	recv = 0;
}

/* ==================== Uart\uart.h ==================== */
#ifndef _UART_H_
#define _UART_H_
#include "main.h"

void UART_Send_Byte(uchar send_byte);
void UART_Send_Str(uchar *send_str);
void UART_Init(void);

#endif

一、单总线通信

DHT11 将湿度敏感元件、NTC 温度敏感元件、模数转换及校准数据封装在传感器内部。单片机不需要测量模拟电压,只需按照规定时序从 DATA 引脚接收数字结果。

这里所说的“单总线”是 DHT11 自己的单线时序协议,不应与 Dallas/Maxim 的 1-Wire 协议混为一谈。DHT11 没有 ROM 地址和总线枚举机制,通常是一只传感器独占一个 GPIO。

1.1 实验演示

实验由 51 单片机开发板、OLED 和 DHT11 模块组成:

DHT11 模块引脚连接作用
VCC5 V 或 3.3 V给模块供电,具体允许范围以模块手册为准
DATAP1.2单片机和传感器共用的数据线
GNDGND电源与信号的共同参考点

烧录配套程序后,OLED 上的 H 表示相对湿度,T 表示温度。用手靠近或握住传感器时,湿度通常会较快变化,温度变化相对缓慢。读数改变只能说明采集链路能够工作,不能据此判断测量精度;DHT11 的典型教学模块精度约为湿度 ±5%RH、温度 ±2℃。

程序每隔约 1 s 读取一次数据,这是必要限制,不宜在主循环中连续无间隔读取。上电后也应至少等待约 1 s,让传感器越过不稳定阶段。

1.2 单总线通信

DHT11 的 DATA 线既由单片机驱动,也由传感器驱动。通信开始时单片机负责产生启动信号,随后释放线路,由 DHT11 返回响应和 40 位测量数据。因此,“只有一根数据线”并不等于只有一根接线,电源线和地线仍不可缺少。

一次完整读取的方向如下:

sequenceDiagram
    participant MCU as 51单片机
    participant BUS as DATA总线
    participant DHT as DHT11
    MCU->>BUS: 拉低至少18 ms
    MCU->>BUS: 释放总线,等待20~40 μs
    DHT->>BUS: 拉低约80 μs作为响应
    DHT->>BUS: 拉高约80 μs作为准备
    loop 40位,最高位先发送
        DHT->>BUS: 约50 μs低电平
        DHT->>BUS: 高电平约26~28 μs表示0,约70 μs表示1
    end
    DHT->>BUS: 拉低约50 μs后释放
1.2.1 电路

裸 DHT11 是四引脚器件;常见蓝色模块通常只引出 VCC、DATA、GND 三个引脚,并在板上集成 DATA 上拉电阻和电源指示灯。两者不要按外观混接。

                 VCC(3.3 V 或 5 V)
                    │
             ┌──────┴──────┐
             │             [Rpull-up]
           [100 nF]          │  典型约5 kΩ
             │               ├──────── DATA ───── P1.2
             │          ┌────┴────┐
             └──────────┤ VDD DATA│
                        │  DHT11   │
             GND ───────┤ GND  NC │
                        └─────────┘
                              NC悬空

各部分的作用:

  • 上拉电阻:无人主动拉低 DATA 时,把线路恢复为高电平。它不是限流电阻,也不是用来“放大”信号。线越长,寄生电容越大,上升沿越慢;手册给出的短距离典型值约为 5 kΩ,长线应结合供电和波形调试。
  • 100 nF 去耦电容:紧靠传感器 VDD 与 GND,给瞬态电流提供局部回路并抑制电源噪声。模块上若已经安装,可不重复堆叠,但仍要确认。
  • DATA:双向共享线路。经典 8051 准双向口写 1 后相当于释放线路,才能让 DHT11 拉低。若换成推挽 GPIO 的 MCU,必须切换为输入或开漏模式,不能在 DHT11 拉低时仍由 MCU 强推高电平。
  • GND:单片机和传感器必须共地,否则 DATA 的高低电平没有共同参考。

配套开发板原理图中,P1.2 还连接 LED3 支路,因此 DHT11 通信时 LED 可能闪动。这不是额外的通信指示器,而是同一 GPIO 的电平变化同时影响了 LED。开发板 LED 从 +5 V 经 LED、电阻接到端口,属于低电平点亮;占用 P1.2 时还应留意该支路对波形的负载。

接线前先断电,确认 VCC 与 GND 后再上电。排针错位可能把电源和地短接,造成 USB 口保护、开发板掉电甚至器件损坏。

1.2.2 DHT11温湿度传感器模块手册

驱动传感器时最重要的不是记住某段程序,而是从手册提取四类约束:供电与引脚、测量范围、启动/响应时序、数据帧格式。代码中的拉低、延时、循环和校验都能在这四类信息中找到依据。

1.2.2.1 传感器性能说明
项目DHT11 手册参数使用含义
温度范围0~50℃超出范围不能保证有效
温度精度最大约 ±2℃适合教学和一般环境指示
湿度范围20%~90%RH(25℃条件)湿度有效范围会受温度条件影响
湿度精度最大约 ±5%RH不适合高精度计量
分辨率温度 1℃、湿度 1%RHDHT11 通常只提供整数级读数
采样间隔不小于 1 s读取过快可能得到无效或重复数据
测量电流最大约 2.5 mAGPIO 只接 DATA,不能用 GPIO 给模块供电

相对湿度 RH 是当前空气含水量相对于该温度下饱和含水量的比例。手握传感器同时带来热量和水汽,所以温湿度都可能变化,但传感器响应存在延迟。

1.2.2.2 接口说明

裸传感器正面朝向栅格外壳、引脚向下时,常见编号为:

引脚名称连接
1VDD3~5.5 V 电源
2DATA接 GPIO,并通过上拉电阻接 VDD
3NC不连接,保持悬空
4GND接地

三针模块已经把 NC 隐藏,并可能集成上拉电阻、去耦电容和电源灯。由于不同厂家的三针排列可能不同,必须读模块丝印,不能只按线的颜色判断。

空闲时 DATA 为高电平。这个高电平主要由上拉电阻建立;通信双方通常只需要主动拉低或释放线路,从而避免输出冲突。

1.2.2.3 电源引脚

供电与通信不是两个互不相关的问题。传感器电源波动会直接改变数字阈值和内部测量状态:

USB/稳压电源 ──┬── 51开发板 VCC
               └── DHT11 VDD
共同地 ─────────── 51 GND ─── DHT11 GND

建议将 100 nF 陶瓷电容放在 DHT11 的 VDD、GND 附近。若电机、继电器或舵机与传感器共用电源,还要增加合适的电源隔离和储能电容,否则负载启动造成的压降可能让 DHT11 读数失败。

上电后不要立即发起读取,应等待至少 1 s。DATA 上拉电压必须与单片机 GPIO 可承受电压相容;3.3 V MCU 不能在未确认耐压的情况下把 DATA 上拉到 5 V。

1.2.2.4 通信规则

启动与响应时序可以按控制权交接理解:

空闲       MCU启动             MCU释放       DHT响应             进入数据
DATA  ‾‾‾‾___________________/‾‾‾‾‾________/‾‾‾‾‾‾‾____...
          ≥18 ms              20~40 μs  约80 μs低  约80 μs高
控制者      MCU                  无        DHT11       DHT11

数据位的共同起点都是约 50 μs 低电平,随后用高电平宽度编码:

位0:____/‾‾‾________
        26~28 μs

位1:____/‾‾‾‾‾‾‾‾___
           约70 μs
      ↑
   每位前约50 μs低电平

单片机通常在上升沿后延时约 30~40 μs再采样:此时“0”的高电平已经结束,而“1”仍为高电平。采样时刻不能贴着 28 μs边界,软件延时还必须按实际晶振、指令周期、编译优化和循环开销校准;更稳妥的方法是用定时器测量高电平宽度并设置超时。

DHT11 一次发送 40 位,均为最高位先出:

字节内容
0湿度整数部分
1湿度小数部分
2温度整数部分
3温度小数部分
4校验和

校验规则为:

checksum = (byte0 + byte1 + byte2 + byte3) & 0xFF

DHT11 的小数字节通常为 0,但驱动仍应完整接收,不能直接跳过。只有响应时序、40 位接收和校验都成功后,才应更新屏幕上的温湿度;超时或校验失败时应保留明确的错误状态,避免把半帧数据当作测量值。