ORG 00H
JMP START
ORG 0BH
JMP TIM0
START: MOV TMOD ,#00000001B
MOV IE ,#10000010B
SETB TR0
L1: CALL KEY
CLR EA
JB F0,L1
MOV A,22H
RL A
MOV DPTR ,#TABLE
MOVC A,@A+DPTR
MOV TH0,A
MOV 21H,A
MOV A,22H
RL A
INC A
MOVC A,@A+DPTR
MOV TL0 ,A
MOV 20H,A
L2:CALL KEY
SETB EA
JB F0,L1
JMP L2
KEY:SETB F0
MOV R3,#0F7H
MOV R1,#00H
L3:MOV A,R3
MOV P1,A
MOV A,P1
CLR C
CPL C
MOV R5,#04H
L4:RLC A
JNC KEYIN
INC R1
DJNZ R5,L4
MOV R3,A
CLR C
CPL C
RRC A
MOV A,R3
JC L3
RET
KEYIN: MOV 22H,R1
CLR F0
RET
TIM0:PUSH ACC
PUSH PSW
MOV TL0,20H
MOV TH0,21H
CPL P3.0
POP PSW
POP ACC
RETI
TABLE: DW 64021, 64103,64260,64400
DW 64524, 64580,64684,64777
DW 64820, 64898,64968,65030
DW 65058, 65110,65157,64178
END