温度测量 ADS7841

#include<reg51.h> #include<absacc.h rel='nofollow' onclick='return false;'> #include<intrins.h> #include <ctype.h> sbit clk=P1^0; sbit cs=P1^1; sbit din=P1^2; sbit busy=P1^3; sbit dout=P1^4; sbit ledl=P1^6;//温度显示上极限 sbit ledh=P1^7;//温度显示下极限 unsigned char led[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90}; unsigned int t=0; unsigned char result[4];//温度各位存放表 unsigned char a=0; void delay(unsigned int t)//延时程序 { unsigned int i; for(i=0;i<t;i++); } void Timer0() interrupt 1 //定时扫描显示 { TH0 = 0xf6; TL0 = 0x3b; switch(a) { case(0): {a=1; P2 = 0x01; P0=led[result[0]]; break;} case(1): {a=2; P2 = 0x02; P0=led[result[1]]; break;} case(2): {a=3; P2 = 0x04; P0=led[result[2]]; break;} case(3): {a=0; P2 = 0x08; P0=led[result[3]]; break;} default: break; } } main() { float tempreture; unsigned int adresult; ledl=0; ledh=0; P2 = 0x00; P0=0x00; //LED TMOD=0x01; TH0=0xf6;//5ms TL0=0x3b; IE=0x82; //51中断初始化 TR0=1; clk=0; //ads7841初始化 cs=1; din=0; dout=1; busy=0; while(1) { unsigned char control=0x97; unsigned char i; cs = 0; _nop_(); for(i=0;i<8;i++) //控制命令传送 { clk=0; _nop_(); if((control&0x80)==0x80) din=1; else din=0; clk=1; _nop_(); control<<=1; } clk = 0; _nop_(); /*读ADS7841的转换数据*/ while(busy) { clk=0; _nop_(); clk=1; _nop_(); }; /*当BUSY脚由高变为低时，则开始数据输出*/ for(i=0;i<12;i++)//数据传送 { clk=1; _nop_(); clk=0; _nop_(); adresult<<=1; adresult=adresult|(unsigned int)dout; } for(i=0;i<4;i++) { clk=0; _nop_(); clk=1; _nop_(); } clk=0; cs=1; delay(50000); tempreture= adresult*0.0244;//转换成温度 t=tempreture; //t=t*10; result[0]=(t/10)%10; result[1]=t%10; result[2]=0; result[3]=0; if(result[0]==9) //温度报警 ledh=1; else ledh=0; if(result[0]==0) ledl=1; else ledl=0; } }