AT89C51 program on AT89S51

Hello,
I have the problem that I have a program that works on the AT89C51, but not on the AT89S51.
A simple program (blink.c) works on both MC.
AT89C51 with #include <at89c51RC2.h>
AT89S51 with #include <at89x52.h>
Compiler = Keil C version 9.60.7.0
The program for AT89S51
#include <at89x52.h>
#include <stdio.h>
#include <stdlib.h>
#include <absacc.h>
#include <float.h>
#include <string.h>


#define LCD_ADR XBYTE[0xF800]		 // Basisadresse : Daten in das Befehlsregister
																 // schreiben
#define LCD_ADR1 XBYTE[0xF801]	 // Basisadresse +1: Daten in das Datenregister
			                           // schreiben
#define LCD_ADR2 XBYTE[0xF802]	 // Basisadresse +2: Inhalt des Befehlsregister
			                           // lesen
#define LCD_ADR3 XBYTE[0xF803]   // Basisadresse +3: Inhalt des Datenregister
			                           // lesen
																 
//#define LCD_ADR *((unsigned char volatile xdata*)0xF800)	
//#define LCD_ADR1 *((unsigned char volatile xdata*)0xF801)
//#define LCD_ADR2 *((unsigned char volatile xdata*)0xF802)
//#define LCD_ADR3 *((unsigned char volatile xdata*)0xF803)

#define LCD_INI1 0x01						 // Clear Display
#define LCD_INI2 0x02						 // Cursor Home
#define LCD_INI3 0x06						 // Entry Mode Set  06
#define LCD_INI4 0x0F						 // Display On, Cursor blink
#define LCD_INI5 0x14						 // Cursor/Display Shift  14
#define LCD_INI6 0x38						 // Funktion Set
#define ADDR1 0x80  						 // Cursoradresse Zeichen 0-7
#define ADDR2 0xC0  						 // Cursoradresse Zeichen 8-15

#define CURSOR_FLASH 0x0F					// Cursor blink

sbit P10 = P1^0;
sbit P14 = P1^4;


unsigned char code string1[]="******TEST******";

void lcd_init(void);
void lcd_clear(void);
void lcd_addr1(void);
void lcd_addr2(void);
void lcd_sendstring(unsigned char[]);
void lcd_out_char(unsigned char);
void delay(int);                                //sub routine for delay
void delay_init(void);


void main()
 {
	 P10 = 0;
	 P14 = 0;
	 lcd_init();
	 delay_init();
	 lcd_sendstring(string1);		// 
	 delay(10000);
	 lcd_clear();
	 delay(10000);
}
 
void delay(int value )   //Delay Function
{
     int i,j;
     for(i=0;i<=value;i++)
     for(j=0;j<=5;j++);
}

 
void delay_init()
 {
   int i;
   for(i=0;i<=1000;i++);               //software delay
 }  
 
void lcd_init()
{
	LCD_ADR = 0x38;
	delay_init();
	LCD_ADR = 0x38;
	delay_init();
	LCD_ADR = 0x38;
	delay_init();
	LCD_ADR = 0x0C;
	delay_init();
	LCD_ADR = 0x01;
	delay_init();
	LCD_ADR = 0x02;
	delay_init();
} 

void lcd_clear()
{
	LCD_ADR = LCD_INI1;
	delay_init();
	LCD_ADR = LCD_INI2;
	delay_init();
}

void lcd_sendstring(unsigned char text[])
{
	unsigned char b;
	int i = 0, l = 0;
	
	l = 16;
	//lcd_addr1();
	for(i = 0; i <= l; i++)
	{
		if(i < 8)
		{
			b = text[i];
			lcd_out_char(b);
			LCD_ADR = ADDR1+i+1;
		}
		if(i == 8) lcd_addr2();
		if(i > 8 && i < 17)
		{
			b = text[i-1];
			lcd_out_char(b);
			LCD_ADR = ADDR2+i-8;
			
		}
	}
}

void lcd_out_char(unsigned char letter)
{
	LCD_ADR1 = letter;
	delay_init();
}	

// Cursor auf Zeichen 0 setzen
void lcd_addr1()
{
	LCD_ADR = ADDR1;
	delay_init();
}

// Cursor auf Zeichen 8 setzen
void lcd_addr2()
{
	LCD_ADR = ADDR2;
	delay_init();
}