ORG 4000H
MOV DPTR,#1B03H
MOV A,#82H
MOVX @DPTR,A
KEY:ACALL KEYTZ
JNZ LK2
AJMP KEY
LK2:MOV R2,#0FEH
MOV R4,#00H
LK4:MOV DPTR,#1B00H
MOV A,R2
MOVX @DPTR,A
INC DPL
MOVX A,@DPTR
JB AcC.1,LONE
MOV A,#00H
lkp:add a,r4
acall disup
ajmp key

LONE:JB ACC.0,NEXT
MOV A,#08H
ajmp lkp
NEXT:INC R4
MOV A,R2
JNB ACC.7,KND
RL A
MOV R2,A
AJMP LK4
KND:AJMP KEY
KEYTZ:MOV DPTR,#1B00H
MOV A,#00H
MOVX @DPTR,A
INC DPL
MOVX A,@DPTR
CPL A
ANL A,#03H
RET
SHOWDATA:DB 00H,01H,02H,03H,04H,05H,06H,07,08H,09H,0AH,0bh,0CH,0DH,0EH,0FH
DISUP:MOV DPTR,#SHOWDATA
MOVC A,@A+DPTR
MOV DPTR,#1B02H
MOVX @DPTR,A
RET
END