please let me know ,i can use MAX232 to control the temperature and
Humidity use DAQ SYStem Code ??i think set upper value and lower to 8051 thought
vb. the DAQ code in here
i want to control only 2 sensor is posible ???
my circuit is correctly?

/***********************************************************
Data Aquisition amp Logging System
Author: Abbas Raza
************************************************************/

#include ltreg51.hgt

sbit start=P3^3;
sbit end=P3^4;
sbit oe=P3^5;
sbit ale=P3^6;
//sbit clock=P3^2;
//sbit relay1=P1^3;
//sbit relay2=P1^4;
//sbit relay3=P1^5;
//sbit relay4=P1^6;
unsigned char temp;
unsigned char aray[]={’0′,’1′,’2′,’3′,’4′,’5′,’6′,’7′,’8′,’9′};
void delay()
{
int k,l;
for(k=0;klt40;k++)
for(l=0;llt80;l++);
}
void initSerial()
{
TMOD=0×22;
TH1=0xFD;
SCON=0×50;
TR1=1;
EA=1;
ES=1;
}
void usDelay(int a)
{
TH0=256-(a/1.085);
TR0=1;
ET0=1;
}
void timerRoutine() interrupt 1
{
clock=~clock;
}
void sendChar(unsigned char ch)
{
SBUF=ch;
while(!TI);
TI=0;
}
void serialRoutine() interrupt 4
{
if(RI==1)
{
temp=SBUF;
switch(temp)
{
case(‘a’):
relay1=1;
break;
case(‘b’):
relay1=0;
break;
case(‘c’):
relay2=1;
break;
case(‘d’):
relay2=0;
break;
case(‘e’):
relay3=1;
break;
case(‘f’):
relay3=0;
break;
case(‘g’):
relay4=1;
break;
case(‘h’):
relay4=0;
}
RI=0;
}
}
void sendReading(unsigned char val)
{
unsigned char l,m;
l=val%10;
m=(val/10)%10;
sendChar(aray[m]);
sendChar(aray[l]);
sendChar(‘,’);
}
void latch()
{
ale=0;
delay();
ale=1;
}
void startConv()
{
delay();
start=0;
delay();
start=1;
}
void wait()
{
while(end==1);
}
void get()
{
delay();
oe=0;
delay();
oe=1;
}
void main()
{

unsigned char sensor=0,reading;
P1=0;
initSerial();
usDelay(50);
while(1)
{
if(sensor==8)
sensor=0;
if(sensor==0)
sendChar(‘N’);
P1=(P1amp0xf8)+sensor;
latch();
startConv();
wait();
get();
reading=P2;
sendReading(reading);
sensor++;
}
}

Download File IN HERE

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