[51] problem in using adc0808 with lm35 and 8051

[raghavkmr]

i am using following code to see output in lcd of temperature , i dont understand why output is wrong on lcd on proteus i m giving vref = 2.56V

#include<reg51.h>

sfr adcdata = 0x90;		              //assigning adc data to port 1
sfr ldata = 0x80 ;			  //assigning lcd data to port 0
sbit rs=P2^7;		              // assining control pins to port2.5,6,7
sbit rw=P2^6;	
sbit en=P2^5;

// channel selection bits of adc
sbit addr_c=P3^2;			
sbit addr_b=P3^3;
sbit addr_a=P3^4;
 // control pins of adc
sbit ale=P3^5;		             //address latch enble pin   
sbit eoc=P3^6;		            // end of converssion pin
sbit sc=P3^7;		            //select chip pin
sbit oe=P3^1;
sbit wave = P2^4;
	 	void delay(unsigned int k);
	 	void cmd(unsigned char  y);		          //lcd command function	
		void lcddata(unsigned char  y);	 
		void lcdinit(void);	
		unsigned char z;

	 unsigned char convertanddisplay(unsigned char value)
{
    unsigned char x,d1,d2,d3;
   d1=value%10;
   value=value/10;
   d2=value%10;
   value=value/10 ;
   d3=value%10	   ;
   lcddata(d3+0x30) ;
   lcddata(d2+0x30)	 ;
   lcddata(d1+0x30)	  ;
	cmd(0x01);	                       //move data d1 to lcd
   z=d1*100+d2*10+d3;
	delay(1) ;
   return(z);
} 
void timer0(void) interrupt 1
{
wave= ~wave ;
}

void main()
{
  unsigned char value;

TMOD =0x02;
TH0=-1;
IE=0x82;
TR0=1 ;

adcdata=0xff;
eoc =1 ;
ale = 0;
oe=0 ;
lcdinit();
sc=0 ;
while(1)
 {
 	addr_c=0;
	addr_b=0;
	addr_a=1;
	delay(1);
	ale=1;
	delay(1);
	sc=1;
	delay(1);
	ale=0;
	sc=0;
	while(eoc==1);
	while(eoc==0);
	oe=1;
	//delay(1);
	value=adcdata;
	z=	convertanddisplay(value);
	oe=0;		  

	 }
}

void delay(unsigned int k)
{
unsigned int i,j;
for(i=0;i<k;i++)
for(j=0;j<1200;j++);
}

void cmd(unsigned char ch)
  {
	ldata = ch;
	rs = 0;
	rw = 0;
	en = 1;
	delay(1);
	en = 0;
	return;
  }

  void lcddata(unsigned char cm)
  {
	ldata = cm;
	rs = 1;
	rw = 0;
	en = 1;
	delay(1);
	en=0;
	return;
  }
  void lcdinit()	                             //lcd initialize
{
cmd(0x38);                            // 2 lines and 5x7 matrix
cmd(0x0e);                            //display on, cursor blinking
cmd(0x01);                           //clear display screen
cmd(0x06);                           //increment cursor
cmd(0x80);  
}

 

[Golden Electronics]

LCD output wrong means what is black dot or any other please clear ?

 

[jayanth.devarayanadurga]

I don't see PORTS configured as inputs or outputs as needed.