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- #include "1602.h"
- #define u8 unsigned char
- #define u16 unsigned int
- sbit dq=P3^7;
- float t;
- bit start;
- u8 id[8];
- u8 id1[8]={0x28,0xFE,0x27,0xFA,0x03,0x00,0x00,0x58};
- u8 id2[8]={0x28,0x82,0x0F,0xC7,0x05,0x00,0x00,0x7F};
- u8 id3[8]={0x28,0xA1,0xC1,0xC6,0x05,0x00,0x00,0x9F};
- void send_0()
- {
- dq=0;
- delay(30);
- dq=1;
- }
- void send_1()
- {
- dq=0;
- delay(0);
- dq=1;
- delay(30);
- }
- void ds18B20_send_cmd(u8 cmd)
- {
- u8 i,d;
- d=cmd;
- for(i=0;i<8;i++)
- {
- if(d&0x01)
- {
- send_1();
- }
- else
- {
- send_0();
- }
- d>>=1;
- }
- }
- u8 ds18B20_receive()
- {
- u8 i,d;
- for(i=0;i<8;i++)
- {
- d>>=1;
- dq=0;
- delay(0);
- dq=1;
- delay(0);
- if(dq==1)
- {
- d|=0x80;
- }
- delay(35);
- }
- return d;
- }
- u8 ds18b20_start()
- {
- u16 tt;
- dq=0;
- delay(330);
- dq=1;
- delay(30);
- tt=0;
- while(dq==1)
- {
- tt++;
- if(tt>10000)
- {
- return 1;
- }
- }
- tt=0;
- delay(120);
- while(dq==0)
- {
- tt++;
- if(tt>10000)
- {
- return 2;
- }
- }
- return 0;
- }
- float read_n_18b20_temp(u8 *id)
- {
- u8 th,tl;
- u16 temp;
- u8 i;
- start=ds18b20_start();
- ds18B20_send_cmd(0x55);
- for(i=0;i<8;i++)
- {
- ds18B20_send_cmd(id[i]);
- }
- ds18B20_send_cmd(0x44);
- delay(2000);
- start=ds18b20_start();
- ds18B20_send_cmd(0x55);
- for(i=0;i<8;i++)
- {
- ds18B20_send_cmd(id[i]);
- }
- ds18B20_send_cmd(0xbe);
- tl=ds18B20_receive();
- th=ds18B20_receive();
- temp=th;
- temp<<=8;
- temp|=tl;
- if(temp&0x8000)
- {
- temp=~temp+1;
- }
- t=temp*0.0625;
- return t;
- }
- void main()
- {
- float t1,t2,t3;
- LCD_init();
- delay(1000);
- show_char(0x00,'A');
- show_char(0x08,'B');
- show_char(0x40,'C');
- while(1)
- {
- t1=read_n_18b20_temp(id1);
- t2=read_n_18b20_temp(id2);
- t3=read_n_18b20_temp(id3);
- delay(2000);
- show_float(0x02,t1);
- show_float(0x42,t2);
- show_float(0x0A,t3);
- }
- }
- //------------------------------------------
復(fù)制代碼
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