ORG 00H
JMP MAIN
ORG 0003H
JMP INT0
ORG 000BH
JMP T0
ORG 0013H
JMP INT1
MAIN:SETB EA
     SETB ET0
     SETB EX0
     SETB EX1
     CLR IT0
     MOV TMOD,#1
     MOV TH0,#3CH
     MOV TL0,#0B0H
     MOV 70H,#0
     MOV 71H,#0
     MOV 72H,#10
     MOV 73H,#0
     MOV 74H,#0
     MOV 75H,#10
     MOV 76H,#0
     MOV 77H,#0
     MOV R5,#20
     MOV R3,#3
     SETB TR0
 DD: MOV A,70H
     MOV R7,A
     MOV R6,#0FEH
     CALL DISPLAY
   CALL DELAY
     MOV A,71H
     MOV R7,A
     MOV R6,#0FDH
     CALL DISPLAY
     CALL DELAY

      MOV A,72H
     MOV R7,A
     MOV R6,#0FBH
     CALL DISPLAY
      CALL DELAY

      MOV A,73H
     MOV R7,A
     MOV R6,#0F7H
     CALL DISPLAY
      CALL DELAY

      MOV A,74H
     MOV R7,A
     MOV R6,#0EFH
     CALL DISPLAY
     CALL DELAY

      MOV A,75H
     MOV R7,A
     MOV R6,#0DFH
     CALL DISPLAY
     CALL DELAY

      MOV A,76H
     MOV R7,A
     MOV R6,#0BFH
     CALL DISPLAY
     CALL DELAY

      MOV A,77H
     MOV R7,A
     MOV R6,#7FH
     CALL DISPLAY
     CALL DELAY
      JMP DD

T0:MOV TH0,#3CH
     MOV TL0,#0B0H
     DJNZ R5,KK
      MOV R5,#20
     INC 70H
     MOV R4,70H
     CJNE R4,#10,KK
     MOV 70H,#0
     INC 71H
     MOV R4,71H
     CJNE R4,#6,KK
     MOV 71H,#0
     INC 73H
     MOV R4,73H
     CJNE R4,#10,KK
     MOV 73H,#0
     INC 74H
     MOV R4,74H
     CJNE R4,#6,KK
     MOV 74H,#0
     INC 76H
     MOV R4,76H
     CJNE R4,#4,PP
     CALL UU
  PP:CJNE R4,#10,KK
     MOV 76H,#0
     INC 77H
 KK:  RETI
 UU:DJNZ R3, PP
    MOV R3,#3
    MOV 76H,#0
    MOV 77H,#0
    RET
    
INT0:CLR TR0       
     INC 73H     
     MOV R4,73H
     CJNE R4,#10,HH
     MOV 73H,#0
     INC 74H
     MOV R4,74H
     CJNE R4,#6,HH
     MOV 74H,#0
  HH:
     SETB TR0
     RETI
INT1:CLR TR0        
     INC 76H
     MOV R4,76H
     CJNE R4,#4,PQ
     CALL UT
  PQ:CJNE R4,#10,MK
     MOV 76H,#0
     INC 77H
  MK:SETB TR0   
     RETI
 UT:DJNZ R3, PQ
    MOV R3,#3
    MOV 76H,#0
    MOV 77H,#0
    RET
    
DISPLAY:MOV A,R7
        MOV DPTR,#TAB
        MOVC A,@A+DPTR
        MOV P0,A
        MOV P2,R6

        RET
TAB:  DB  0C0H,0F9H,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H,0BFH  ;  0，1，2，3，4，5，6，7，8，9，-

 DELAY:MOV R1,#10
     D4:MOV R2,#50
     DJNZ R2,$
     DJNZ R1,D4
     RET