8051 microcontroller programming:Tutorial-Fibonacci series in assembly with Keil

Fibonacci series is also a good practice code:
The sequence is: 1,1,2,3,5,8.............
PROGRAM:

 ORG 00H
  MOV DPTR,#2000H
  MOVX A,@DPTR
  DEC A
  DJNZ A,LOOP2
  INC DPTR
  MOV A,#01H
  MOVX @DPTR,A
  INC DPTR
  MOV A,#01H
  MOVX @DPTR,A
  END 
LOOP2: MOV R1,A
  INC DPTR
  MOV A,#01H
  MOVX @DPTR,A
  INC DPTR
  MOV A,#01H
  MOVX @DPTR,A
LOOP1: DEC DPL
  MOVX A,@DPTR
  MOV R2,A
  INC DPTR
  MOVX A,@DPTR
  ADD A,R2
  INC DPTR
  MOVX @DPTR,A
  DJNZ R1,LOOP1
  END