Liquid crystal display

#include<reg52.h>
#define DB P0
sbit RS=P2^6;
sbit RW=P2^5;
sbit E=P2^7;
void chushi();
void lcdshow(unsigned char x,unsigned char y,unsigned char *str);
void xiezhiling(unsigned char cmd);
void main()
{
unsigned char str[]="I LOVE U";
	chushi();// initial 
	lcdshow(4,0,str);
	lcdshow(1,1,"hello chengdu");
	while(1);
}

void chushi()
{
	xiezhiling(0x38);
	xiezhiling(0x0C);//0000 1DCB D=1 Turn on the display ;D=0 Turn off the display ;C=1 Show cursor ;C=0 Close the cursor ;B=1 The cursor blinks ;B=0 The cursor does not flash 
	xiezhiling(0x06);//0000 01NS N=1 Pointer plus one ;N=0 Pointer minus one ;S=1,N=1 Move left ;S=1,N=0 Move right ;S=0 Don't move 
	xiezhiling(0x01);// All pointers are clear 0
}

void jiance()
{
	unsigned char sta;
	DB=0xFF;// Keep yourself high before reading 
	RS=0;
	RW=1;
	do{
		E=1;
		sta=DB;
		E=0;
	  }while(sta & 0x80);// Check whether the highest bit is 0
}

					void xiezhiling(unsigned char cmd)// Write instructions 
					{
						jiance();
						RS=0;
						RW=0;
						E=1;
						DB=cmd;
						E=0;
					}


										void lcdwrdat(unsigned char dat)// Writing data 
										{
											jiance();
											RS=1;
											RW=0;
											E=1;
											DB=dat;
									    E=0;
										}

																			void lcdc(unsigned char x,unsigned char y)// Regard LCD as x and y Axis 
																			{
																				unsigned char addr;
																				if(y==0)// When y Shaft for 0 when 
																				addr=0x00+x;// first line 00 To 0F
																				else
																			addr=0x40+x;// The second line 40 To 4F
																			xiezhiling(addr|0x80);
																			}

void lcdshow(unsigned char x,unsigned char y,unsigned char *str)
{
	lcdc(x,y);
	while(*str!='\0')// Not equal to space 
	{
		lcdwrdat(*str++);// First value at ++,* and ++ The same level is preferred 
	}
}