I am giving my full code so that u can detect my fault easily.

#include<stdio.h>
#include<string.h>
#include<regx52.h>
#include<stdlib.h>

static unsigned long overflowcount=0;

void delay(void);
void lcdcommand(unsigned char);
void lcdinit(void);
void lcdout(char * );
void timecount(void);
void timer(void);



void timer1_ISR() interrupt 3
{

overflowcount++;

}

void timer()
{
TMOD=(TMOD&0x0f)|0x20;
TH1=0;
TL1=TH1;
ET1=1;
TR1=1;
EA=1;

}

void timecount()
{

lv:
if(overflowcount!=1800)
goto lv;

}


void main(void)
{
unsigned char port;

char s0[]="0.0";
char s10[]="10.0";
char s20[]="20.0";
char s30[]="30.0";
char s40[]="40.0";
char s50[]="50.0";
char s60[]="60.0";
char s70[]="70.0";
char s80[]="80.0";
char s90[]="90.0";
char s100[]="100.0";

char sp[9]="---";






timer();
lcdinit();

port=P1;

switch(port)
{

case (0X28):
lcdout(s0);
break;
case (0X29):
case (0X2A):
case (0X2B):
case (0X2C):
case (0X2D):
case (0X2E):
case (0X2F):
case (0X30):
case (0X31):
case (0X32):
case (0X33):
case (0X34):
case (0X35):
case (0X36):
case (0X37):
lcdout(s10);
break;

case (0X38):
case (0X39):
case (0X3A):
case (0X3B):
case (0X3C):
case (0X3D):
case (0X3E):
case (0X3F):
case (0X40):
case (0X41):
case (0X42):
case (0X43):
case (0X44):
case (0X45):
case (0X46):
case (0X47):
case (0X48):
lcdout(s20);
break;
case (0X49):
case (0X4A):
case (0X4B):
case (0X4C):
case (0X4D):
case (0X4E):
case (0X4F):
case (0X50):
case (0X51):
case (0X52):
case (0X53):
case (0X54):
case (0X55):
case (0X56):
case (0X57):
lcdout(s30);
break;
case (0X58):
case (0X59):
case (0X5A):
case (0X5B):
case (0X5C):
case (0X5D):
case (0X5E):
case (0X5F):
case (0X60):
case (0X61):
case (0X62):
case (0X63):
case (0X64):
case (0X65):
case (0X66):
lcdout(s40);
break;
case (0X67):
case (0X68):
case (0X69):
case (0X6A):
case (0X6B):
case (0X6C):
case (0X6D):
case (0X6E):
case (0X6F):
case (0X70):
case (0X71):
case (0X72):
case (0X73):
case (0X74):
case (0X75):
lcdout(s50);
break;
case (0X76):
case (0X77):
case (0X78):
case (0X79):
case (0X7A):
case (0X7B):
case (0X7C):
case (0X7D):
case (0X7E):
case (0X7F):
case (0X80):
case (0X81):
case (0X82):
case (0X83):
case (0X84):
lcdout(s60);
break;
case (0X85):
case (0X86):
case (0X87):
case (0X88):
case (0X89):
case (0X8A):
case (0X8B):
case (0X8C):
case (0X8D):
case (0X8E):
case (0X8F):
case (0X90):
case (0X91):
case (0X92):
case (0X93):
lcdout(s70);
break;
case (0X94):
case (0X95):
case (0X96):
case (0X97):
case (0X98):
case (0X99):
case (0X9A):
case (0X9B):
case (0X9C):
case (0X9D):
case (0X9E):
case (0X9F):
case (0XA0):
case (0XA1):
case (0XA2):
lcdout(s80);
break;
case (0XA3):
case (0XA4):
case (0XA5):
case (0XA6):
case (0XA7):
case (0XA8):
case (0XA9):
case (0XAA):
case (0XAB):
case (0XAC):
case (0XAD):
case (0XAE):
case (0XAF):
case (0XB0):
case (0XB1):
lcdout(s90);
break;
case (0XB2):
case (0XB3):
case (0XB4):
case (0XB5):
case (0XB6):
case (0XB7):
case (0XB8):
case (0XB9):
case (0XBA):
case (0XBB):
case (0XBC):
case (0XBD):
case (0XBE):
case (0XBF):
case (0XC0):
case (0XC1):
case (0XC2):
case (0XC3):
lcdout(s100);
break;
default :
lcdout(sp);
break;
}





}

void lcdinit()
{

lcdcommand(0x38);
lcdcommand(0x10);
lcdcommand(0x01);
lcdcommand(0x06);
lcdcommand(0x0C);
lcdcommand(0x03);


}

void lcdcommand(unsigned char cmd)
{
P3=0x10;
P2=cmd;
P3=0x00;
delay();


}

void lcdout(char *s )
{
int i;
for(i=0; i<strlen(s); i++)
{
P3=0x14;
P2=s[i];
P3=0x04;
delay();

}
timecount();
overflowcount=0;

}

void delay()
{
int i;
for(i=0;i<100;i++)
;

}