DHT21应用在AT89S52和stc89C52单片机例程.docx

****************************************************************////DHT21使用范例//单片机:AT89S52或STC89C52RC//功能://硬件连接:,DHT11的电源和地连接单片机的电源和地,单片机串口加MAX232连接电脑//公司:万瑞和电子//****************************************************************//#include<>#include<>//typedefunsignedcharU8;/*definedforunsigned8-bitsintegervariable无符号8位整型变量*/typedefsignedcharS8;/*definedforsigned8-bitsintegervariable有符号8位整型变量*/typedefunsignedintU16;/*definedforunsigned16-bitsintegervariable符号16位整型变量*/typedefsignedintS16;/*definedforsigned16-bitsintegervariable无有符号16位整型变量*/typedefunsignedlongU32;/*definedforunsigned32-bitsintegervariable无符号32位整型变量*/typedefsignedlongS32;/*definedforsigned32-bitsintegervariable有符号32位整型变量*/typedeffloatF32;/*singleprecisionfloatingpointvariable(32bits)单精度浮点数(32位长度)*/typedefdoubleF64;/*doubleprecisionfloatingpointvariable(64bits)双精度浮点数(64位长度)*///#defineucharunsignedchar#defineuintunsignedint#defineData_0_time4//----------------------------------------------////----------------IO口定义区--------------------////----------------------------------------------//sbitP2_0=P2^0;//----------------------------------------------////----------------定义区--------------------////----------------------------------------------//U8U8FLAG,k;U8U8count,U8temp;U8U8T_data_H,U8T_data_L,U8RH_data_H,U8RH_data_L,U8checkdata;U8U8T_data_H_temp,U8T_data_L_temp,U8RH_data_H_temp,U8RH_data_L_temp,U8checkdata_temp;data;U8outdata[5];//定义发送的字节数U8indata[5];U8count,count_r=0;U8str[5]={"RS232"};U16U16temp1,U16temp2;SendData(U8*a){outdata[0]=a[0];outdata[1]=a[1];outdata[2]=a[2];outdata[3]=a[3];outdata[4]=a[4];count=1;SBUF=outdata[0];}voidDelay(U16j){U8i;for(;j>0;j--){for(i=0;i<27;i++);}}voidDelay_10us(void){U8i;i--;i--;i--;i--;i--;i--;}(void){U8i;for(i=0;i<8;i++){U8FLAG=2;while((!P2_0)&&U8FLAG++);Delay_10us();Delay_10us();Delay_10us();U8temp=0;if(P2_0)U8temp=1;U8FLAG=2;while((P2_0)&&U8FLAG++);//超时则跳出for循环if(U8FLAG==1)break;//判断数据位是0还是1//data<<=1;data|=U8temp