WDJ.rar_DS18B20 protues_DS18B20 仿真_wdj

#include<reg51.h> #define uint unsigned int #define uchar unsigned char sbit DQ=P3^3; uchar code ditab[16]={0x00,0x01,0x01,0x02,0x02,0x03,0x04,0x04,0x05,0x06,0x06,0x07,0x07,0x08,0x09,0x09}; uchar data temp_data[2]={0x00,0x00}; uchar data display[5]={0x00,0x00,0x00,0x00,0x00}; uchar code choose[4]={0x70,0xb0,0xd0,0xe0}; uchar code table[22]={ 0x3F,0x06,0x5B,0x4F, 0x66,0x6D,0x7D,0x07, 0x7F,0x6F,0x77,0x7C, 0x39,0x5E,0x79,0x71, 0x37,0x0E,0x71,0x3E, 0x00,0x40 }; void delay(uchar t) { while(--t);//2t+5us } void Reset()//对DS18B20复位操作 { DQ=1; delay(1); DQ=0; delay(250);//拉低505us DQ=1; delay(15);//等待35us while(DQ); while(~DQ); delay(20); DQ=1; } void WriteData(uchar cod)//对DS18B20写操作 { uint i; for(i=0;i<=7;i++) { DQ=1; delay(1); DQ=0; delay(1);//拉低9us DQ=cod&0x01; delay(35);//保持75us cod>>=1; } DQ=1; delay(3); } uchar ReadData()//对DS18B20读操作 { uint i; uchar dat=0; for(i=0;i<=7;i++) { DQ=1; delay(1); dat>>=1; DQ=0; delay(1);//拉低7us DQ=1; delay(1);//拉高7us if(DQ)dat|=0x80; delay(35); } DQ=1; return(dat); } void work() { Reset(); //初始化 WriteData(0xcc); //发跳过ROM 命令(ROM命令) WriteData(0x44); //启动温度转换（MEMORY命令） delay(250); //等待转换结束 Reset(); //初始化 WriteData(0xcc); //发跳过ROM 命令（ROM命令） WriteData(0xbe); //发读取温度命令（MEMORY 命令） temp_data[0]=ReadData(); //读温度值低 8位（提取数据） temp_data[1]=ReadData(); //读温度值高 8位 } void seg() { uchar n=0; if(temp_data[1]>127) { temp_data[1]=(255-temp_data[1]); temp_data[0]=(255-temp_data[0]); n=1; } display[4]=temp_data[0]&0x0f; display[0]=ditab[display[4]]; display[4]=((temp_data[0]&0xf0) >> 4)|((temp_data[1]&0x0f)<<4); display[3]=display[4] / 100; display[1]=display[4] % 100; display[2]=display[1] / 10; display[1]=display[1] % 10; if(!display[3]) { display[3]=20; if(!display[2]){display[2]=20;} } if(n){display[3]=21;} } main() { uint i,h; while(1) { work(); seg(); for(h=0;h<500;h++) { for(i=0;i<=3;i++) { P2=choose[i]; P0=table[display[i]]; if(i==1)P0=P0+0x80; delay(150); } } } }