#include<pic.h>#define uchar unsigned char#define uint unsigned int#define rs_h (PORTC|=0x01)#define rs_l (PORTC&=0xfe)#define rs_o (TRISC&=0xfe)#define rw_h (PORTC|=0x02)#define rw_l (PORTC&=0xfd)#define rw_o (TRISC&=0xfd)#define en_h (PORTC|=0x04) #define en_l (PORTC&=0xfb)#define en_o (TRISC&=0xfb)#define temp_h (PORTC|=0x08) #define temp_l (PORTC&=0xf7) #define temp_o (TRISC&=0xf7)#define temp_i (TRISC|=0x08)#define led_o (TRISC&=0xef)#define led_l (PORTC&=0xef)#define led_h (PORTC|=0x10)#define LCD PORTBuchar dat1,dat2;//保存读出的温度zunsigned long int dat;void delayms(uint x) //4M晶振下，延时1ms{uint y,z;for(y=x;y>0;y--)for(z=110;z>0;z--);}void Ds18b20_reset(void)//DS18B20初始化{uint count;uchar i,flag=1;temp_o;temp_l;for(count=60;count>0;count--);//延时480ustemp_i;while(flag){if(RC3)flag=1;elseflag=0;}led_o;led_l;//开指示灯for(count=60;count>0;count--);//延时480us}void Ds18b20_write(uchar datt)//向DS18B20写一个字节{uchar count;uchar i;temp_o;for(i=8;i>0;i--){temp_o;temp_l;for(count=1;count>0;count--);if(datt&0x01==0x01)temp_i;else{temp_o;temp_l;}for(count=23;count>0;count--);//延时60ustemp_i;for(count=1;count>0;count--);datt>>=1;}}uchar Ds18b20_read(void) //从DS18B20读一个字节{uchar i,datt;uchar count;for(i=8;i>0;i--){datt>>=1;temp_o;temp_l;for(count=1;count>0;count--);temp_i;//改为输入方向时，上拉电阻把数据线拉高，释放总线，此语句必须有，参考datasheet的P15for(count=1;count>0;count--);if(RC3)datt|=0x80;for(count=23;count>0;count--);//延时60us}return datt;}void lcd_com(uchar com)//向LCD1602写命令{ rs_o;rw_o;en_o;TRISB=0x00;//配置RB为输出方向rs_l;rw_l;LCD=com;delayms(1);en_h;delayms(1);en_l;delayms(1);}void lcd_dat(uchar dat)//向LCD1602写数据{ rs_o;rw_o;TRISB=0x00;//配置RB为输出方向en_o;rs_h;rw_l;LCD=dat;delayms(1);en_h;delayms(1);en_l;delayms(1);}void lcd_write(uchar c,uchar r,uchar dat)//向LCD1602指定行、指定列、写数据{lcd_com(0x80+0x40*c+r);lcd_dat(dat);delayms(1);}void lcd_init(void)//LCD1602初始化，初始化后第一行显示temperature:,第二行显示.C{lcd_com(0x38);lcd_com(0x0c);lcd_com(0x06);lcd_write(0,2,0x54);lcd_write(0,3,0x65);lcd_write(0,4,0x6d);lcd_write(0,5,0x70);lcd_write(0,6,0x65);lcd_write(0,7,0x72);lcd_write(0,8,0x61);lcd_write(0,9,0x74);lcd_write(0,10,0x75);lcd_write(0,11,0x72);lcd_write(0,12,0x65);lcd_write(0,13,0x3a);lcd_write(1,11,0xdf);lcd_write(1,12,0x43);}void show(void)//把温度值送LCD1602显示{uchar flag;uchar t[4];uint temp;if(dat2>=240){dat= (~(dat2*256+dat1)+1)*(0.0625*10);//取反加一，保留一位小数flag=1;}else{dat=(dat2*256+dat1)*(0.0625*10);flag=0;};temp=dat%10;t[0]=(0x30+temp);temp=dat%100;temp=temp/10;t[1]=(0x30+temp);temp=dat%1000;temp=temp/100;t[2]=(0x30+temp);temp=dat/1000;t[3]=(0x30+temp);if(flag==1)//负温度显示{lcd_write(1,10,t[0]);lcd_write(1,9,0xa5);lcd_write(1,8,t[1]);lcd_write(1,7,t[2]);lcd_write(1,6,t[3]);lcd_write(1,5,0x2d);}if(flag==0)//正温度显示{lcd_write(1,10,t[0]);lcd_write(1,9,0xa5);lcd_write(1,8,t[1]);lcd_write(1,7,t[2]);lcd_write(1,6,t[3]);lcd_write(1,5,0x20);//显示空格，刷掉负号}}void main(void){lcd_init();while(1){Ds18b20_reset();Ds18b20_write(0xcc);Ds18b20_write(0x44);//发送温度转换命令delayms(1000);//延时1s，等待温度转换完成Ds18b20_reset();Ds18b20_write(0xcc);Ds18b20_write(0xbe);//发送读温度寄存器命令dat1=Ds18b20_read();dat2=Ds18b20_read();show();led_h;//关指示灯delayms(2000);}}//调试总结://某IO口8位未全使用时，对整个IO口读取进行位运算无效
