Code:
//****************************************************************//
// Program for AM230x series
//MCU: AT89S52 , Frequency of crystal oscillator: 11.0592MHz
//Function: Transmit RH & Temp. Data via PC interface , Baud rate 9600
//Connection: P2.0 connected with DHT sensor
// Company : Aosong Electronics
//****************************************************************//
//
//
#include <reg51.h>
#include <intrins.h>
//
typedef unsigned char U8; /* defined for unsigned 8-bits integer variable */
typedef signed char S8; /* defined for signed 8-bits integer variable */
typedef unsigned int U16; /* defined for unsigned 16-bits integer variable */
typedef signed int S16; /* defined for signed 16-bits integer variable */
typedef unsigned long U32; /* defined for unsigned 32-bits integer variable */
typedef signed long S32; /* defined for signed 32-bits integer variable */
typedef float F32; /* single precision floating point variable (32bits) */
typedef double F64; /* double precision floating point variable (64bits) */
//
#define uchar unsigned char
#define uint unsigned int
#define Data_0_time 4
//----------------------------------------------//
//----------------Definition for IO interface--------------------//
//----------------------------------------------//
sbit P2_0 = P2^0 ;
sbit P2_1 = P2^1 ;
sbit P2_2 = P2^2 ;
sbit P2_3 = P2^3 ;
//----------------------------------------------//
//----------------Definition zone--------------------//
//----------------------------------------------//
U8 U8FLAG,k;
U8 U8count,U8temp;
U8 U8T_data_H,U8T_data_L,U8RH_data_H,U8RH_data_L,U8checkdata;
U8 U8T_data_H_temp,U8T_data_L_temp,U8RH_data_H_temp,U8RH_data_L_temp,U8checkdata_temp;
U8 U8comdata;
U8 outdata[5];
U8 indata[5];
U8 count, count_r=0;
U8 str[5]={"RS232"};
U16 U16temp1,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];
}
//
//
void Delay(U16 j)
{ U8 i;
for(;j>0;j--)
{
for(i=0;i<27;i++);
}
}
void Delay_10us(void)
{
U8 i;
i--;
i--;
i--;
i--;
i--;
i--;
}
//
//
void COM(void)
{
U8 i;
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++);
if(U8FLAG==1)break;
U8comdata<<=1;
U8comdata|=U8temp; //0
}//rof
}
//--------------------------------
//-----Sub-program for reading %RH ------------
//--------------------------------
//----All the variable bellow is global variable--------
//----Temperature's high 8bit== U8T_data_H------
//----Temperature's low 8bit== U8T_data_L------
//----Humidity's high 8bit== U8RH_data_H-----
//----Humidity's low 8bit== U8RH_data_L-----
//----Check-sum 8bit == U8checkdata-----
//--------------------------------
void RH(void)
{
P2_0=0;
Delay(5);
P2_0=1;
Delay_10us();
Delay_10us();
Delay_10us();
Delay_10us();
P2_0=1;
if(!P2_0)
{
U8FLAG=2;
while((!P2_0)&&U8FLAG++);
U8FLAG=2;
while((P2_0)&&U8FLAG++);
COM();
U8RH_data_H_temp=U8comdata;
COM();
U8RH_data_L_temp=U8comdata;
COM();
U8T_data_H_temp=U8comdata;
COM();
U8T_data_L_temp=U8comdata;
COM();
U8checkdata_temp=U8comdata;
P2_0=1;
U8temp=(U8T_data_H_temp+U8T_data_L_temp+U8RH_data_H_temp+U8RH_data_L_temp);
if(U8temp==U8checkdata_temp)
{
U8RH_data_H=U8RH_data_H_temp;
U8RH_data_L=U8RH_data_L_temp;
U8T_data_H=U8T_data_H_temp;
U8T_data_L=U8T_data_L_temp;
U8checkdata=U8checkdata_temp;
}//fi
}//fi
}
//----------------------------------------------
// main()
//----------------------------------------------
void main()
{
U8 i,j;
TMOD = 0x20;
TH1 = 253;
TL1 = 253;
TR1 = 1;
SCON = 0x50;
ES = 1;
EA = 1;
TI = 0;
RI = 0;
SendData(str) ;
Delay(1);
while(1)
{
//------------------------
// Transfer humiture read subroutine
RH();
//--------------------------
str[0]=U8RH_data_H;
str[1]=U8RH_data_L;
str[2]=U8T_data_H;
str[3]=U8T_data_L;
str[4]=U8checkdata;
SendData(str) ;
Delay(20000);
}//elihw
}// main
void RSINTR() interrupt 4 using 2
{
U8 InPut3;
if(TI==1)
{
TI=0;
if(count!=5)
{
SBUF= outdata[count];
count++;
}
}
if(RI==1)
{
InPut3=SBUF;
indata[count_r]=InPut3;
count_r++;
RI=0;
if (count_r==5)
{
count_r=0;
str[0]=indata[0];
str[1]=indata[1];
str[2]=indata[2];
str[3]=indata[3];
str[4]=indata[4];
P0=0;
}
}
}
