lcd keypad of lpc 2148 arm

#include <LPC214X.H>
void init_keyb(void);
void init_lcd(void);
unsigned char read_key(void);
unsigned char decode(int, int);
int get_row(int);
int get_col(int);
unsigned char mat(int, int);
void cmd(unsigned char);
void datal(unsigned char);
void delay(int);

int main ()
 { 

 

  unsigned char f=0xFF;			  //for unpressed key


  // PINSEL0 = 0x00000000;		// Enable GPIO on all pins
// PINSEL1 = 0x00000000;
// PINSEL2 = 0x00000000;


  init_keyb();
  init_lcd();
  
  while (1)
   {
	f = read_key();
    if (f!=0xFF)				  //if no key is pressed then continue polling
    datal(f);
	else
	continue;
   }
 }


void init_keyb(void)
 {
  IODIR1 = 0x00000000;			  //making rows as I/P and columns as O/P
 }

void init_lcd(void)
 {
  IODIR0 = 0x007F0000;

  cmd(0x28);
  cmd(0x01);
  cmd(0x02);
  cmd(0x06);
  cmd(0x0C);

 }

unsigned char read_key()
 {
  int row=0,col=0,i;
  unsigned char f=0xFF;
  
  IOSET1 = 0x01E00000;		      //making rows as I/P and columns as O/P

  row = IOPIN1 & 0x001E0000;

  IOSET1 = 0x001E0000;			  //making rows as O/P and columns as I/P

  col = IOPIN1 & 0x01E00000;

  IOSET1 = 0x01E00000;			  //making rows as I/P and columns as O/P

  f = decode(row,col);

  return (f);
 }


unsigned char decode(int row, int col)
 {
  int r=0,c=0;
  unsigned char f=0xFF;

  r=get_row(row);

  c=get_col(col);

  if (r!=0xFF && c!=0xFF)
     f=mat(r,c);
  else
     f=0xFF;
  return (f);
 }

unsigned char mat(int r, int c)
 {
  unsigned char m[4][4]={{'A','B','C','D'},
                         {'E','F','G','H'},
						 {'I','J','K','L'},
						 {'M','N','O','P'},
                        };
  unsigned char f;
  f=m[r][c];
  return (f);
 }

int get_row(int row)
 {
  int r=0xff;
  
  switch (row ^ 0x001E0000)
   {
    case 0x00020000:
	     r=0;
	     break;

	case 0x00040000:
	     r=1;
		 break;

	case 0x00080000:
	     r=2;
		 break;

	case 0x00100000:
	     r=3;
		 break;

	default:
	  	 break;
   }
  return (r);
 }

int get_col (int col)
 {
  int c=0xff;
  
  switch (col ^ 0x01E00000)
   {
    
	case 0x00200000:
	     c=0;
		 break;

	case 0x00400000:
	     c=1;
		 break;

	case 0x00800000:
	     c=2;
		 break;

	case 0x01000000:
	     c=3;
		 break;

	default:
	     break;
   }
  return (c);
 }

void cmd(unsigned char com)
 {
  int a=0;
  a=com&0xF0;
  a=a<<15;

  IOCLR0 = 0x007f0000;
  IOSET0 = 0x00010000;
  
  IOSET0 = a;
  delay(10000);

  IOCLR0 = 0x00010000;
  
  a=com&0x0F;
  a=a<<19;

  IOCLR0 = 0x007f00;
  IOSET0 = 0x00040000;

  IOSET0 = a;
  delay(10000);

  IOCLR0 = 0x00040000;
 }

void datal(unsigned char d)
 {
  int b=0;
  b=d&0xF0;
  b=b<<15;

  IOCLR0 = 0x007f0000;
  IOSET0 = 0x00050000;

  IOSET0 = b;
  delay(10000);

  IOCLR0 = 0x00040000;

  b=d&0x0F;
  b=b<<19;

  IOCLR0 = 0x007f00;
  IOSET0 = 0x00070000;

  IOSET0 = b;
  delay(10000);

  IOCLR0 = 0x00040000;
 }

void delay(int count)
 {
  int i=0,j=0;
  for (i=0;i<count;i++)
     for (j=0;j<35;j++);
 }