main: mov r2,#07h
      mov r3,#18h
      mov   r0,#79h    ;顯示器的始端口
      mov   r1,#02h    ;拆為非壓縮的BCD數的計數
      acall loop2
      mov   a,r6      ;拆為非壓縮的BCD數
      acall loop4
      mov   a,r5
      acall loop4
main1:acall disp
      ajmp  main1

loop2:clr   a            ;二進制轉換為十進制
      mov   r4,a
      mov   r5,a
      mov   r6,a
      mov   r7,#16
loop3:clr   c
      mov   a,r3
      rlc   a
      mov   r3,a
      mov   a,r2
      rlc   a             ;c為bi
      mov   r2,a          ;(r4r5r6)+(r4r5r6)=(r4r5r6)*2+c
                          ;十進制加
      mov   a,r6
      addc  a,r6
      da    a
      mov   r6,a
      mov   a,r5
      addc  a,r5
      da    a
      mov   r5,a
      mov   a,r4
      addc  a,r4
      da    a
      mov   r4,a
      djnz  r7,loop3
      ret

loop4:push  a
      anl   a,#0fh       ;拆為非壓縮的BCD數
      mov   @r0,a
      inc   r0
      pop   a
      swap  a
      djnz  r1,loop4
      mov   r1,#02h
      ret

disp: mov  r0,#79h        ;設79H-7C為顯示緩沖器
      mov  r3,#1
      mov  a,#0efh
gg:   mov  r4,a         ;數碼管動態顯示
      mov  p2,a
      mov  a,@r0
      mov  dptr,#aa
      movc a,@a+dptr
ee:   mov  p0,a
      acall bb
      inc  r0
      MOV    A,R3
      JB     ACC.3,ff
      RL     A
      MOV    R3,A
      mov    a,r4
      rl     a
      SJMP   gg
ff:   ret
aa:   DB     0EDH,28H,0CBH,0ABH,2EH         ;0,1,2,3,4
      DB     0A7H,0E7H,29H,0EFH,0AFH	    ;5,6,7,8,9
bb:   MOV    R7,#02H	                    ;延時子程序
cc:   MOV    R6,#0FFH
dd:   DJNZ   R6,dd
      DJNZ   R7,cc
      RET
      end