program to access a switch .if switch is pressed to increment the count in 8051

/*program to access a switch .if switch is pressed to increment the count */

#include<reg51.h>

#include"lcd.c"

sbit sw1=P3^2;

#define led P1;

char flag;

char count;

void uart_init(void);

void uart_tr(char);

void uart_init()

{

 SCON=0x50;

 TMOD=0x20;

 TH1=253;

 TR1=1;

 }

void uart_str(char *str)

{

 while(*str)

 {

  uart_tr(*str++);

 }

}

 void isr(void) interrupt 0

 {

 if(sw1==0)

                flag=1;

}

void uart_tr(char s)

{

 SBUF=s;

 while(TI==0);

 TI=0;

}

void main()

{

 EA=EX0=IT0=1;

 EX1=IT1=1;

 uart_init();

 init_lcd();

 uart_str("start count\n");

 while(1)

 {

 

  

                 if(flag==1)

                  {

                                flag=0;

                   count+=1;

                   //count1+=1;

                  }

                if(count>=0)

                {

                  P1=count;

                  uart_tr(count+0x30);

                cmd_lcd(0x01);

                puts_lcd(" count:=");

                puti_lcd(count);

                delay_ms(100);

                }

 }//while

}