Hiển thị chữ lên LCD

Code:
#include <REGX52.H>
#include <stdio.h>
sbit RS = P1^0;
sbit RW = P1^1;
sbit EN = P1^2;
char x;
void delay30ms(void)
{
TMOD = 0x10;
TH1 = 35535/256;
TL1 = 35535%256;
TR1 = 1;
while (!TF1);
TR1 = TF1=0;
}
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);
write_command(0x06);
write_command(0x0c);
}
void main(void)
{
delay30ms();
init();

write_command(0x01);
delay(10);
write_command(0x80);
write_string(" DUY TAN ");
delay(10);
write_command(0xc0);
write_string (" KHOA DIEN TU");
while(1);
}