ADC implementation in PIC18LF4550

#include <p18f4550.h>
#include <delays.h>
#include <htc.h>

#define rs LATCbits.LATC0
#define rw LATCbits.LATC1
#define en LATCbits.LATC2

#define _XTAL_FREQ 20000000

__CONFIG (1, FOSC_HS);
__CONFIG (2, WDTDIS & PWRTEN & BORDIS & LVPDIS);

void lcd_init(void);
void disp(unsigned int);
void commd(unsigned int);
void adc_init();
void readADC(unsigned int);
void adc_conv(unsigned int);
void Delay10KTCYx(unsigned char unit);
void Delay1KTCYx(unsigned char unit);

unsigned char out[20]="ADC OUT=";
unsigned int count = 0;
unsigned int result;

void main(void)
{
TRISA = 0x04;
LATA = 0x00;
TRISC = 0x00;
LATC = 0x00;
TRISD = 0x00;
LATD = 0x00;
TRISE = 0x00;
LATE = 0x00;

Delay10KTCYx(200);
lcd_init();
while(out[count]!='\0')
{
disp(out[count]);
count++;
}
adc_init();
while (1)
{
readADC(result);
adc_conv(result);// Function to convert the decimal vaule to its corresponding ASCII
Delay1KTCYx (240);
}
}

void adc_init()
{
// configure A/D convertor
ADCON0bits.ADON = 0; // Disable A/D module
ADCON1 = 0x0C;
//Read port AN2
ADCON0bits.CHS0 = 0;
ADCON0bits.CHS1 = 1;
ADCON0bits.CHS2 = 0;
ADCON0bits.CHS3 = 0;
//Set FOSC/32
ADCON2bits.ADCS0 = 0;
ADCON2bits.ADCS1 = 1;
ADCON2bits.ADCS2 = 0;
// Acquisition time (2TAD)
ADCON2bits.ACQT0 = 1;
ADCON2bits.ACQT1 = 0;
ADCON2bits.ACQT2 = 0;
TRISAbits.TRISA2 = 1; // input
ADCON0bits.ADON = 1; //Turn on ADC
}

void readADC(unsigned int result)
{
Delay10KTCYx( 5 ); // Delay for 50TCY
ADCON0bits.GO = 1; // Code for starting A/D conversion
while (ADCON0bits.GO!= 0); // Wait until the A/D conversion is over
PORTE = ADRESH;
result = ADRESH;
Delay1KTCYx (240);
}

void adc_conv(unsigned int result)
{
unsigned int result_new;
int i = 0;
char position = 0xC0;
for(i=0; i<=3; i++)
{
result_new = result%10; // To exract the unit position digit
result = result/10;
commd(position);
disp(48 + result_new); // Convert into its corresponding ASCII
position++;
}
}
void lcd_init(void)
{
en = 0;
rs = 0;
rw = 0;

Delay10KTCYx( 10 );

commd(0x33); // Set interface to 8-bit
Delay10KTCYx( 5 );  

commd( 0x33 ); // Set interface to 8-bit
Delay10KTCYx( 1 );   

commd( 0x33 ); // Set interface to 8-bit
Delay10KTCYx( 1 );   

commd( 0x28 ); // Set interface to 4-bit

commd( 0x28 ); // Function Set

commd(0x0C); // Display On and Cursor Off

commd(0x01); // Clear display screen
Delay10KTCYx( 5 );  

commd(0x06); // Increment cursor

}

void disp(unsigned int character)
{

PORTD=character >> 4;

rs = 1;
rw = 0;
en = 1;
en = 0;

PORTD=character & 0x0f;

rs = 1;
rw = 0;
en = 1;
en = 0;

Delay1KTCYx(1);

}

void commd(unsigned int commd)
{

PORTD=commd >> 4;
rs = 0;
rw = 0;
en = 1;
en = 0;

PORTD=commd &0x0f;
rs = 0;
rw = 0;
en = 1;
en = 0;

Delay1KTCYx(1);

}