51

51单片机应用系统典型模块开发大全

#include <reg51.h>
#define uchar unsigned char
#define uint  unsigned int

sbit DQ=P1^0;							//DS18B20数据I/O口
sbit din=P3^0;							//MAX7221数据输入端
sbit CS=P3^1;							//MAX7221片选输入端
sbit clk=P3^2;							//MAX7221时钟输入端

uchar code disp_dot[]={
    0xfe,0xb0,0xed,0xf9,
    0xb3,0xdb,0xdf,0xf0,
    0xff,0xfb,
};			//共阴极显示代码
uchar code dispcode[]={
    0x7e,0x30,0x6d,0x79,
    0x33,0x5b,0x5f,0x70,
    0x7f,0x7b,0x01,0x00
};			//共阴极显示代码
uchar code CrcTable[256]={
    0,94,188,226,97,63,221,131,194,156,126,32,163,253,31,65,
    157,195,33,127,252,162,64,30,95,1,227,189,62,96,130,220,
    35,125,159,193,66,28,254,160,225,191,93,3,128,222,60,98,
    190,224,2,92,223,129,99,61,124,34,192,158,29,67,161,255,
    70,24,250,164,39,121,155,197,132,218,56,102,229,187,89,7,
    219,133,103,57,186,228,6,88,25,71,165,251,120,38,196,154,
    101,59,217,135,4,90,184,230,167,249,27,69,198,152,122,36,
    248,166,68,26,153,199,37,123,58,100,134,216,91,5,231,185,
    140,210,48,110,237,179,81,15,78,16,242,172,47,113,147,205,
    17,79,173,243,112,46,204,146,211,141,111,49,178,236,14,80,
    175,241,19,77,206,144,114,44,109,51,209,143,12,82,176,238,
    50,108,142,208,83,13,239,177,240,174,76,18,145,207,45,115,
    202,148,118,40,171,245,23,73,8,86,180,234,105,55,213,139,
    87,9,235,181,54,104,138,212,149,203,41,119,244,170,72,22,
    233,183,85,11,136,214,52,106,43,117,151,201,74,20,246,168,
    116,42,200,150,21,75,169,247,182,232,10,84,215,137,107,53
};
uchar code SN[8][7]={
    0x00,0x00,0x00,0xB8,0xC5,0x30,0x28,
    0x00,0x00,0x00,0xB8,0xC5,0x31,0x28,
    0x00,0x00,0x00,0xB8,0xC5,0x32,0x28,
    0x00,0x00,0x00,0xB8,0xC5,0x33,0x28,
    0x00,0x00,0x00,0xB8,0xC5,0x34,0x28,
    0x00,0x00,0x00,0xB8,0xC5,0x35,0x28,
	0x00,0x00,0x00,0xB8,0xC5,0x36,0x28,
	0x00,0x00,0x00,0xB8,0xC5,0x37,0x28,
};
/*各检测回路上DS18B20内部的64位ROM中的后7个字节，CRC字节可以通过调用
CRC()函数计算获得*/
uchar disp_buf[5]={0x00,0x00,0x00,0x00,0x00};   //显示数据缓冲区
uchar Tem_H,Tem_L;								//用于存储温度转换值高8位和低8位
bit Flag=0;										//正、负温度值符号标志位，0为正，1为负

/************************函数声明***********************/
void delay(int us);								//延时函数
bit Init_DS18B20(void);							//DS18b20初始化函数
uchar Read_bit(void);							//DS18b20读一个字节
void Write_bit(uchar val_bit);					//DS18b20写一个字节
uchar Read_byte(void);							//DS18B20读字节函数
void Write_byte(uchar com);						//DS18B20写字节函数
int ReadTemperature(uchar n);					//DS18b20读取温度
void Match_ROM(uchar n);						//寻找ROM匹配DS18B20						
uchar CRC(uchar n,uchar j);						//计算CRC校验字节函数
void  display(void);							//显示函数
void Init_MAX7221(void);						//MAX7221初始化函数
void Write_7221(uchar com,uchar da);			//MAX7221写字节程序
void adj_dat(uchar m);							//显示字节调整函数
void l_delay(int n);							//延时函数
/*********************主函数***********************/
void main()
{
	uchar i;
	Init_MAX7221();
	while(1)
	{	 
		for(i=0;i<8;i++)
		{
			adj_dat(i);							//显示字节调整函数
			display();							//显示函数
			l_delay(500);						//延时
		}
	}	 
}
/*******************MAX7221初始化********************/
void Init_MAX7221(void)
{
    Write_7221(0x0c,0x01);						//正常工作状态,关断模式
	Write_7221(0x09,0x00);						//译码选择，非BCD码
	Write_7221(0x0a,0x0f);						//亮度调节
	Write_7221(0x0b,0x07);						//显示位数
}
/*****************MAX7221写字节程序********************/
void Write_7221(uchar com,uchar da)
{
    uchar temp,i,j;
    CS=0;
    clk=0;
    for (i=0;i<8;i++)							//发送命令
    {
        temp=com;
        if ((temp&(0x80>>i))!=0)
            din=1;
        else din=0;
        clk=1;
        for (j=0;j<5;j++);
        clk=0;
    }
    for (i=0;i<8;i++)							//发送数据
    {
        temp=da;
        if ((temp&(0x80>>i))!=0)
            din=1;
        else din=0;
        clk=1;
        for (j=0;j<5;j++);
        clk=0;
    }
    CS=1;
}
/**********************延时函数**************************/
void delay(int us)
{
	int i;
	for(i=0;i<us;i++);							//11.0592MHz下，延时时间为(24+16*us)
}
/**********************延时函数**************************/
void l_delay(int n)
{
	int i,j;
	for(i=0;i<n;i++)
		for(j=0;j<1000;j++);
}
/*******************DS18B20复位函数***********************/
bit Init_DS18B20(void)
{
	bit res;
	DQ=0;										//拉低DQ线
	delay(29);									//延时480us
	DQ=1;										//DQ线置高
	delay(10);									//延时
	res=DQ;										//读取复位响应信号
	delay(10);
	return(res);								//返回响应值
}
/*******************DS18B20读位函数***********************/
uchar Read_bit(void)
{
	uchar i;
	DQ=0;										//拉低DQ线
	DQ=1;										//DQ线置高
	for(i=0;i<3;i++);							//延时15us
	return(DQ);									//返回当前读取值
}

/*******************DS18B20写位函数***********************/
void Write_bit(uchar val_bit)
{
	DQ=0;										//拉低DQ
	if(val_bit==1)DQ=1;							//从DQ线发送1
	delay(5);									//延时
	DQ=1;
}

/********************DS18B20读字节函数*********************/
uchar Read_byte(void)
{
	uchar i;
	uchar temp=0;
	for(i=0;i<8;i++)
	{
		if(Read_bit())temp|=0x01<<i;			//向temp写入读取位
		delay(6);
	}
	return(temp);								//返回读取字节
}

/*********************DS18B20写字节函数*******************/
void Write_byte(uchar com)
{
	uchar i,temp;
	for(i=0;i<8;i++)
	{
		temp=com>>i;							//右移i次取低位发送
		temp&=0x01;
		Write_bit(temp);
	}
	delay(5);
}

/*****************DS18B20A校验位计算函数**************/
uchar CRC(uchar n,uchar j)
{
    uchar i,crc_data=0;
    for (i=0;i<j;i++)							//查表校验
        crc_data=CrcTable[crc_data^SN[n][7-1-i]];
    return(crc_data);
}

/*****************DS18B20 ROM匹配程序*****************/
void Match_ROM(uchar n)
{
	uchar i,temp;
	temp=CRC(n,7);
	Write_byte(0x55); 							//调用ROM匹配指令
	for(i=0;i<7;i++)
	{
		Write_byte(SN[n][7-1-i]);				//结算校验值
	}
	Write_byte(temp);
}

/*****************温度值正负判断程序******************/
uint Get_Tem(uchar dath,uchar datl)
{
	uint temp=0,temp_h=0,temp_l;	
	temp_h=(uint)dath;
	temp=temp_h&0x00ff;
	temp_l=(uint)datl;
	temp_l&=0x00ff;
	temp=(temp<<8)|temp_l;						//去掉符号值后合并成16位数据
	if((dath&0x80)==0x80)
	{
		Flag=1;
		temp=~temp+1;							//负数时求补
	}
	else
	{
		Flag=0;
	}
	return(temp);
}

/***************************温度读取函数****************************/
int ReadTemperature(uchar n)
{
	uint temp=0;
	float temp1=0;
	while(!(Init_DS18B20()));
	Write_byte(0xCC); 							//跳过读序号列号的操作
	Write_byte(0x44); 							//启动温度转换
	while(!(Init_DS18B20()));
	Match_ROM(n);
	Write_byte(0xBE); 							//读取温度寄存器等（共可读9个寄存器） 前两个就是温度
	Tem_L=Read_byte();							//低位
	Tem_H=Read_byte();							//高位
	temp=Get_Tem(Tem_H,Tem_L);
	temp1=temp*0.0625;
	temp=temp1*10+0.5; 
	return(temp);
}
/***************************显示数据处理函数**************************/
void adj_dat(uchar m)
{
	uint temp;
	temp=ReadTemperature(m);					//读温度
	if(Flag)
		disp_buf[0]=10;
	else
		disp_buf[0]=11;
	disp_buf[1]=temp%1000/100;					//显示百位
	if(disp_buf[1]==0)
	{
		disp_buf[1]=disp_buf[0];
		disp_buf[0]=11;
	}	
	disp_buf[2]=temp%100/10;					//显示十位
	disp_buf[3]=temp%10;						//显示个位
	disp_buf[4]=m+1;
}
/*************************显示函数******************************/
void  display(void)
{
	Write_7221(0x02,dispcode[disp_buf[4]]);		//显示
	Write_7221(0x08,dispcode[disp_buf[3]]);		//显示个位
	Write_7221(0x07,disp_dot[disp_buf[2]]);		//显示个位
	Write_7221(0x06,dispcode[disp_buf[1]]);		//显示个位
	Write_7221(0x05,dispcode[disp_buf[0]]);		//显示个位
}