ORG   0000H
		   LJMP  MAIN
		   ORG   0B00H
		   ;LJMP  INT_T0
MAIN:
T02SA      EQU   30H
T02SB      EQU   31H
FLAG       EQU   32H		   

START:     MOV   T02SA,#00H
           MOV   T02SB,#00H
		   CLR   FLAG
		   MOV   TMOD,#01H
		   MOV   TH0,(65536-500)/256
		   MOV   TL0,(65535-500) MOD 256
		   SETB  TR0
		   SETB  ET0
		   SETB  EA
		   SJMP  $
INT_T0:    MOV   TH0,(65536-500)/256
		   MOV   TL0,(65535-500) MOD 256
		   INC   T02SA
		   MOV   A,T02SA
		   CJNE  A,#100,NEXT
		   INC   T02SB 
		   MOV   A,T02SB
		   CJNE  A,#04H,NEXT
		   MOV   T02SA,#00H
		   MOV   T02SB,#00H
		   CPL   FLAG
NEXT:      JB FLAG,DONE
           CPL P1.0
DONE:      RETI
           
		   END