Đếm số lần nhấn nút lên LCD

Code:
#include <REGX52.H>
#include <stdio.h>
#include <string.h>

sbit sw = P3^5;

sbit RS = P1^0;
sbit RW = P1^1;
sbit EN = P1^2;
char x;
void delay_ms(unsigned int ms)
{
unsigned int x,y;
for(x=0;x<ms;x++)
for(y=0;y<=125;y++);
}
void delay(unsigned long int t)
{
unsigned long int i;
for (i=0;i<t;i++);
}
void busy_flag(void)
{
P2 = 0xff;
RS = 0;
RW = 1;
do
{
EN = 0;
delay(10);
EN = 1;
x = P2;
x = x&0x80;
}
while(x==0x80);
}
void write_command(unsigned char LCD_command)
{
busy_flag();
P2 = LCD_command;
RS = 0;
RW = 0;
EN = 1;
delay(50);
EN = 0;
delay(50);
}
void write_data (unsigned char LCD_data)
{
busy_flag();
P2 = LCD_data;
RS = 1;
RW = 0;
EN = 1;
delay(50);
EN = 0;
delay(50);
}
void write_string(char *s)
{
while(*s)
{
write_data(*s);
s++;
}
}

void init(void)
{
write_command(0x03);//
write_command(0x38);//hien thi 2 dong
write_command(0x06);// tro ve dau
write_command(0x0c);// bo dau nhay
}
void restart()
{
write_command(0x01);//xoa man hinh
delay(1000);
}
void startline1()
{
write_command(0x80);//vi tro con tro dau dong 1
delay(1000);
}
void startline2()
{
write_command(0xc0);//vi tri con tro dau dong 2
delay(1000);
}
void write_intnum(unsigned long n)
{
if(n!=0)
{
unsigned char a[11];
int i;
for(i=0;n>0;i++) //tach so
{
a[i]=(n%10)+48;
n=n/10;
}
a[i]=NULL;
for(i=strlen(a);i>=0;i--) //gui so
{
write_data(a[i]);

}
}
else write_data('0');
}

void write_realnum(float n)
{
unsigned long a=n/1; //tach phan nguyen
unsigned long b=(n-a)*10000; //tach phan thap phan
write_intnum(a); // gui phan nguyen
if(b!=0) //gui phan thap phan va dau "."
{
write_data('.');
write_intnum(b);
}
}
void main(void)
{
unsigned int count;
TMOD=0x60;
TH1=0x00;
sw=1;
TR1=1;

while(1)
{
delay_ms(30);
init();
count=TL1;
if (count >99)
{
count = 0;
TL1=0;

}
write_intnum(count);
delay_ms(10);

}
}