温度测量18b20程序.rar_18B20 串口_18b20 温度_18b20串口_测量_温度测量

#include <AT89X51.h> #include <intrins.h> #define TMPort P1_7 unsigned char MYWD[7]={0,0,0,0,0,'`','C'},DS1820ERR[]="NO DS1820!",TMCL[]={"TMCL"}; unsigned char disbuf[10]={0}; unsigned char trance=0,recived=0,comno=0,comzf;//发送状态、接受命令字符序号、接收的字符 unsigned int t; bit DS1820ON,readtm;//DS1820响应、是否接收测温命令。 void initUart(void)//波特率9600，24M时钟 { TMOD|=0x20; SCON=0x50; PCON|=0x80; TH1=0xf3; TL1=0xf3; TR1=1; ES=1; } void uart(void) interrupt 4 { unsigned char m=0; if(RI) {comzf=SBUF;RI=0;recived=1;} else {TI=0;trance=1;} } void Delay_110(void) //延时110微秒，24M晶振 {EA=0; #pragma asm MOV R0,#34H MOV R1,#02H TSR2: DJNZ R0,TSR2 MOV R0,#34H DJNZ R1,TSR2 #pragma endasm EA=1;} void Delay_510(void) //延时510微秒，24M晶振 {EA=0; #pragma asm nop nop MOV R0,#7DH MOV R1,#04H TSR1: DJNZ R0,TSR1 MOV R0,#7DH DJNZ R1,TSR1 #pragma endasm EA=1;} void InitDS1820(void) //初始化DS1820 { EA=0; TMPort = 1; //拉高TMPort _nop_();//保持一个周期 _nop_(); TMPort = 0; //拉低TMPort Delay_510(); //延时 DS1820复位时间要500us的低电平 TMPort = 1; //拉高TMPort Delay_110(); //延时110us 等待DS1820回应 if (!TMPort) //回应信号为低电平 {DS1820ON=1;} else {DS1820ON=0;} Delay_110(); //延时 Delay_110(); TMPort=1; //拉高TMPort EA=1; } void ds1820command(unsigned char a) //写ds1820命令函数。 { EA=0; #pragma asm MOV A,R7 MOV R2,#8 CLR C WR1: CLR TMPort MOV R3,#2//延时3us,24M时钟 DJNZ R3,$ RRC A MOV TMPort,C MOV R3,#68//延时70us DJNZ R3,$ SETB TMPort NOP NOP NOP NOP DJNZ R2,WR1 SETB TMPort #pragma endasm EA=1;} void ds1820rd(unsigned char *pt)//读ds1820数据 { EA=0; #pragma asm MOV R4,#9 MOV A,R1 MOV R0,A RD18201: MOV R2,#8 RD18202: SETB TMPort NOP//延时2us,24M时钟 NOP NOP NOP CLR TMPort//写时间片开始 NOP//延时2us,24M时钟 NOP NOP NOP SETB TMPort//置为高电平，准备输入数据 MOV R3,#10//延时11us,24M时钟 DJNZ R3,$ MOV C,TMPort RRC A MOV R3,#48//延时50us,24M时钟 DJNZ R3,$ DJNZ R2,RD18202 MOV @R0,A INC R0 DJNZ R4,RD18201 #pragma endasm EA=1;} void tmtoc (void) { unsigned char sign;//符号、实际温度的10倍整数 int tm; //实际温度的10倍 sign=disbuf[1]&0x20; if (sign)//disbuf[1]高五位为符号位，判断符号根据补码存储方式，得出真实温度 {disbuf[0]=~disbuf[0];//精确到0.1度，四舍五入 disbuf[1]=~disbuf[1]; tm=((int)disbuf[1]*256+(int)disbuf[0]+1)*0.625+0.5;} else tm=((int)disbuf[1]*256+(int)disbuf[0])*0.625+0.5; //tmof10=(int)tm;//输出温度各位的ASCii码 if (tm>=1000) MYWD[0]='1'; else if (sign) MYWD[0]='-'; else MYWD[0]='+'; MYWD[1]=tm/100%10+'0'; if (MYWD[0]=='0'&&MYWD[1]=='0')MYWD[1]='\0'; MYWD[2]=tm/10%10+'0'; MYWD[3]='.'; MYWD[4]=tm%10+'0'; } void disp(char *p,unsigned char m) //输出一个字符数组,p为数组名，m为字符个数 { unsigned char i; i=EA; EA=1; for(;*p!=0&&m!=0;p++,m--) { SBUF=*p; while(trance==0); trance=0; } EA=i; } void TMCLSHOW(void) { InitDS1820();//发出启动转化温度指令：初始化、skiprom、启动转化 if (!DS1820ON) {disp(DS1820ERR,12);} ds1820command(0xCC); ds1820command(0x44); TMPort=1; for (t=0;t<1500;t++) Delay_510();//等待转化过程完成 InitDS1820();//读RAM中数据：初始化、skiprom、读命令、保存数据 ds1820command(0xcc); ds1820command(0xbe); ds1820rd(disbuf); //disp(disbuf,9); tmtoc(); disp("NOW,temperature is:",20); disp(MYWD,7); disp("\n",1); } void main(void) { DS1820ON=0; //DS1820是否存在 initUart(); InitDS1820();//发出启动转化温度指令：初始化、skiprom、启动转化 if (!DS1820ON) {disp(DS1820ERR,12);} P1=0x55; TMCLSHOW(); P1=0x33; EA=1; while (1) if (recived==1)//判断是否为温度测量命令 {if(comzf==TMCL[comno]) {comno++; if (comno>3) {comno=0; TMCLSHOW(); } } else comno=0; recived=0; } }