跑马灯19.asm

单片机写的程序都含有Protues仿真结果

   ; 逐个熄灭
org 0000h
   r: clr p3.0
      clr p3.1
      clr p3.2
      mov a,#00h
      mov p0,a
      mov a,#0ffh
      mov r0,#08h
  l4: mov p0,a
      lcall delay
      rlc a
      clr c    
      djnz r0,l4
      anl a,#00h 
      mov p0,a
      ljmp r

delay:mov r1,#100
  kk3:mov r2,#300
  kk2:mov r3,#300
  kk1:djnz r3,kk1
      djnz r2,kk2
      djnz r1,kk3
      ret
      end