PIC单片机(PIC16F877A)DS18B20温度传感器驱动程序

2019-04-15 11:50发布

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#include #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 PORTB uchar dat1,dat2;//保存读出的温度z unsigned 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480us temp_i; while(flag) { if(RC3) flag=1; else flag=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60us temp_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P15 for(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

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