program to implement analog to digital conversion using ADC0808 [Embedded systems Lab]

//program to implement analog to digital conversion using ADC0808***//

//* programed by hiq test equipment//

#include<reg51.h>

sbit rs  = P2^0;

sbit en  = P2^1;

sbit db7 = P2^5;

sbit db6 = P2^4;

sbit db5 = P2^3;

sbit db4 = P2^2;

sbit sw1=P1^0;

sbit sw2=P1^1;

sbit sw3=P1^2;

sbit sw4=P1^3;

#define ADC P0 //acquires analog to digital coverted data

sbit A0= P3^0; //A0 A1 & A2 are analog input channel selection bits

sbit A1= P3^1;

sbit A2= P3^2;

sbit START= P3^3; //start convesion bit

sbit ALE= P3^4; //Select channel according to A0 A1& A2

sbit EOC= P3^5; //end of conversion bit

#define VREF 5.0   //set voltage reference

#define MAX_RES 0xff //set maximum resolution of ADC0808 (8bit)

//#define VREF 2.56    //set voltage reference

//#define MAX_RES 0xff //set maximum resolution of ADC0808 (8bit)

void init_lcd();

void cmd_lcd(unsigned char);

void write_lcd(unsigned char);

void display_lcd(unsigned char *);

void integer_lcd(int);

void float_lcd(float);

void delay_ms(unsigned int);

 float  val=0,f;

void main(void)

{

init_lcd();

init_lcd();

delay_ms(100);

init_lcd();

init_lcd();

display_lcd("adc 0808");

delay_ms(1000);

cmd_lcd(0x01);

cmd_lcd(0x01);

while(1)

{

if(sw1==0)

{

do{

cmd_lcd(0x01);

A0=0; //set channel 5

A1=0;

A2=0;

ALE=0;

START=0;

display_lcd("adc val of ch5");

    cmd_lcd(0xc0);

       START=1; //start conversion

       ALE=0; //select channel

       START=0; 

       while(EOC==0); //wait till end of conversion

       float_lcd((5.0*ADC)/MAX_RES);

       display_lcd(" volts");

       delay_ms(1000);

      }while((sw2==0)||(sw3==0)||(sw4==0));

}

else if(sw2==0)

{

do{

cmd_lcd(0x01);

delay_ms(300);

A0=1; //set channel 6

A1=0;

A2=0;

ALE=0;

START=0;

display_lcd("adc val of ch6");

    cmd_lcd(0xc0);

       START=1; //start conversion

       ALE=0; //select channel

       START=0; 

       while(EOC==0); //wait till end of conversion

       float_lcd((VREF*ADC)/MAX_RES);

       display_lcd(" volts");

       delay_ms(1000);

       }while((sw1==0)||(sw3==0)||(sw4==0));

       

}

else if(sw3==0)

{

do{

cmd_lcd(0x01);

delay_ms(300);

A0=0; //set channel 7

A1=1;

A2=0;

ALE=0;

START=0;

display_lcd("adc val of ch7");

    cmd_lcd(0xc0);

       START=1; //start conversion

       ALE=0; //select channel

       START=0; 

       while(EOC==0); //wait till end of conversion

       float_lcd((VREF*ADC)/MAX_RES);

       display_lcd(" volts");

       delay_ms(1000);

}while((sw1==0)||(sw2==0)||(sw4==0));

}

else if(sw4==0)

{

do{

cmd_lcd(0x01);

delay_ms(300);

A0=1; //set channel 8

A1=1;

A2=0;

ALE=0;

START=0;

display_lcd("adc val of ch8");

    cmd_lcd(0xc0);

       START=1; //start conversion

       ALE=0; //select channel

       START=0; 

       while(EOC==0); //wait till end of conversion

       float_lcd((VREF*ADC)/MAX_RES);

       display_lcd(" volts");

       delay_ms(1000);

}while((sw1==0)||(sw2==0)||(sw3==0));

}

}

}

void init_lcd()

{                            

delay_ms(10);

cmd_lcd(0x28);

cmd_lcd(0x0e);

cmd_lcd(0x06);

cmd_lcd(0x01);

delay_ms(10);

}

void cmd_lcd ( unsigned char c )

{

  unsigned char temp;

  temp = c & 0xf0;         //Transmitting high byte

   rs = 0;

  en = 1;

  db7 = temp & 0x80;

  db6 = temp & 0x40;

  db5 = temp & 0x20;

  db4 = temp & 0x10;

  en = 0;

  temp = c & 0x0f;          //Transmitting low byte

  rs = 0;

  en = 1;

  db7 = temp & 0x08;

  db6 = temp & 0x04;

  db5 = temp & 0x02;

  db4 = temp & 0x01;

  en = 0;        

   delay_ms(2);

}

void write_lcd ( unsigned char c )

{

  unsigned char temp;

  temp = c & 0xf0;        //Transmitting high byte

  rs = 1;

  en = 1;

  db7 = temp & 0x80;

  db6 = temp & 0x40;

  db5 = temp & 0x20;

  db4 = temp & 0x10;

  en = 0;

  temp = c & 0x0f;             //Transmitting low byte

   rs = 1;

  en = 1;

  db7 = temp & 0x08;

  db6 = temp & 0x04;

  db5 = temp & 0x02;

   db4 = temp & 0x01;

  en = 0;        

  delay_ms(2); 

}

void display_lcd(unsigned char *s)

{

while(*s)

write_lcd(*s++);

}

void integer_lcd(int n)

{

unsigned char c[6];

unsigned int i=0;

  if(n<0)

  {

    write_lcd('-');

    n=-n;

  }

  if(n==0)

    write_lcd('0');

  while(n>0)

  {

    c[i++]=(n%10)+48;

    n/=10;

  }

  while(i-->=1)

    write_lcd(c[i]);

}

void float_lcd(float f)

{

int n;

float temp;

n=f;

integer_lcd(n);

write_lcd('.');

temp=f-n;

if(temp>=0.00&&temp<=0.09)

write_lcd('0');

f=temp*100;

n=f;

integer_lcd(n);

}

void delay_ms(unsigned int i)

{

unsigned int j;

while(i-->0)

{

for(j=0;j<500;j++)

{

;

}

}

}

save it as ADC.c