Motor RPM using IR and 8051

#include <REG51.h>
#include <stdio.h>

sbit LCD_en=P0^0;      // LCD EN
sbit LCD_rs=P0^1;      // LCD RS 

sbit motor_1_signal=P1^5;
	
unsigned int cnt=0;
unsigned char buf[8];


void msdelay(unsigned int value)
{
 unsigned int i,j;
 for(i=0;i<value;i++)
 for(j=0;j<100;j++);
}

void delay()
{
unsigned int i;
for(i=0;i<1500;i++)
 {
	TMOD = 0x01;    // Timer 0 Mode 1
	TH0= 0xF8;     //initial value for 2ms
	TL0 = 0xCC;
	TR0 = 1;     // timer start
	while (TF0 == 0) // check overflow condition
	{
		if(motor_1_signal==1)
		{
		 cnt=cnt+1;
		 while(motor_1_signal==1);
		}
	}
	TR0 = 0;    // Stop Timer
	TF0 = 0;   // Clear flag
 }
}
	

void main()
{
  unsigned int rpm,i;
  msdelay(20);
  LCD_init();
  lcdclear();
  buz=0;
  lcdrow1();
  LCD_puts("MOTOR-1 RPM");
  while(1)
  {
     cnt=0;
    delay();
    rpm=0;
    rpm=cnt*20;
    for(i=0;i<8;i++)
    buf[i]='\0';
    lcdrow2();
    sprintf(buf, "%d", rpm);
    LCD_puts(buf);		
    LCD_puts("     ");
  }
}