AVR M16 8M 的DS18B20头文件

只需调用gettemp()；就可以了！出口参数wmh是显示的高位，wml使显示的低位，然后调用你的显示程序就可以了！

/*************************************************************************
ds18b20头文件
M16内部8M
*************************************************************************/
#define CLR_DIR_1WIRE DDRC&=~BIT(2) //只要修改这里的参数就可以了！呵呵！
#define SET_DIR_1WIRE DDRC|=BIT(2)//里面什么都不用该！
#define CLR_OP_1WIRE PORTC&=~BIT(2)
#define SET_OP_1WIRE PORTC|=BIT(2)
#define CHECK_IP_1WIRE (PINC & 0x04)//检测
unsigned char wmh,wml;
void init_1820()
{
SET_DIR_1WIRE;//设置PC2 为输出
SET_OP_1WIRE;
CLR_OP_1WIRE;
delay_nus(480);//480us以上
SET_OP_1WIRE;
CLR_DIR_1WIRE;
delay_nus(20); //15~60us
while(CHECK_IP_1WIRE);
SET_DIR_1WIRE;
SET_OP_1WIRE;
delay_nus(140); //60~240us
}
void write_1820(unsigned char x)
{
unsigned char m;
for(m=0;m<8;m++)
{
CLR_OP_1WIRE;
if(x&(1< SET_OP_1WIRE;
else
{CLR_OP_1WIRE;}
delay_nus(40); //15~60us
SET_OP_1WIRE;
}
SET_OP_1WIRE;
}
unsigned char read_1820()
{
unsigned char temp,k,n;
temp=0;
for(n=0;n<8;n++)
{
CLR_OP_1WIRE;
SET_OP_1WIRE;
CLR_DIR_1WIRE;
k=(CHECK_IP_1WIRE);//读数据,从低位开始
if(k)
temp|=(1<else
temp&=~(1<delay_nus(50); //60~120us
SET_DIR_1WIRE;
}
return (temp);
}

void gettemp() //读取温度值
{
unsigned char temh,teml,wm0,wm1,wm2,wm3;
init_1820();//复位18b20
write_1820(0xcc); // 发出转换命令
write_1820(0x44);
//delay_nms(800); //不延时也好使，不知道怎么回事！
init_1820();
write_1820(0xcc);//发出读命令
write_1820(0xbe);
teml=read_1820();//读数据
temh=read_1820();
wm0=teml>>4; //只要高8位的低四位和低8位的高四位，温度范围0~99啦！
wm1=temh<<4;
wm2=wm1+wm0;//16进制转10进制
wm3=wm2/100;
wmh=(wm2%100)/10; //出口参数了！wmh是显示的高位，wml使显示的低位
wml=(wm2%100)%10;
}


//延时程序：

//delay.h
/*-----------------------------------------------------------------------
延时函数
系统时钟：8M
-----------------------------------------------------------------------*/
void delay_1us(void) //1us延时函数
{
asm("nop");
}

void delay_nus(unsigned int n) //N us延时函数
{
unsigned int i=0;
for (i=0;i delay_1us();
}

void delay_1ms(void) //1ms延时函数
{
unsigned int i;
for (i=0;i<1140;i++);
}

void delay_nms(unsigned int n) //N ms延时函数
{
unsigned int i=0;
for (i=0;i delay_1ms();
}