;P1口輸入、輸出

 ORG   0000H
 LJMP  START
 ORG   0030H

START:
       mov   a, #0FEh
       mov   r5, #8
Output:
       mov   P1, a
       mov  p2,a
       mov p3,a
       mov p0,a
       RL    a
       call  Delay
       djnz  r5, Output
       Ljmp  START

Delay:
       mov   r6, #0
       mov   r7, #0
DelayLooP:
       djnz  r7, DelayLoop
       djnz  r6, DelayLoop
       ret

       end