AVR单片机的DS18B20 C语言程序

#include

#define uchar unsigned char

#define uint unsigned int

//

#define BIT_SET(a,b) a|=(1<

#define BIT_CLR(a,b) a&=~(1< //清零位a.b

#define BIT_INV(a,b) a^=(1< //翻转位a.b

#define BIT_STATUS(a,b) a&(1< //读取位a.b

/

#define CLR_DS18B20 BIT_CLR(PORTC,PC7) //数据线强制拉低

#define SET_DS18B20 BIT_SET(PORTC,PC7) //数据线强制拉高，上拉

#define HLD_DS18B20 BIT_SET(DDRC,PC7) //Mega16控制总线

#define RLS_DS18B20 BIT_CLR(DDRC,PC7) //释放总线

#define STU_DS18B20 BIT_STATUS(PINC,PC7) //数据线的状态

uchar const SEG7[10]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};

uchar const ACT[8]={0x08,0x04,0x02,0x01,0x80,0x40,0x20,0x10};

uint T;

//=============================

void delayUs(uchar temp)

{

while(temp--);

}

uchar resetDS18B20(void);

unsigned int readTempDS18B20(void);

void port_init(void)

{

PORTA = 0xFF;

DDRA = 0x00;

PORTB = 0xFF;

DDRB = 0xFF; //输出

PORTC = 0xFF;

DDRC = 0xFF; //输出

DDRD = 0xFF;

PORTD = 0xFF;

}

void delay_ms(uint k)

{

uint i,j;

for(i=0;i

{

for(j=0;j<570;j++);

}

}

//=============================

void display(uchar counter)

{

uchar i;

DDRA=0xff;

DDRC=0xff;

PORTA=0x00;

PORTC=0xff;

for(i=0;i<100;i++)

{

PORTA=SEG7[counter];

PORTC=ACT[3];

delay_ms(10);

PORTA=SEG7[counter/10];

PORTC=ACT[2];

delay_ms(10);

PORTA=SEG7[counter/100];

PORTC=ACT[1];

delay_ms(10);

PORTA=SEG7[counter/1000];

PORTC=ACT[0];

delay_ms(10);

}

}

void main()

{

port_init();

while(1)

{

resetDS18B20();

T=readTempDS18B20();

T=T>>4; //去除ds18b20转换的小数位（低四位）

display(T);

}

}