ORG 0000H
LJMP MAIN
ORG 000BH
LJMP T0ISR
ORG 0030H
MAIN:
MOV TMOD,#01H
MOV TH0,#HIGH(65536-250)
MOV TL0,#LOW(65536-250)
SETB TR0
SETB ET0
SETB EA
MOV R2,#0
SJMP $
T0ISR:
CLR TR0
MOV TH0,#HIGH(65536-250)
MOV TL0,#LOW(65536-250)
SETB TR0
CPL P1.1
INC R2
CJNE R2,#4,T0E
CPL P1.0
MOV R2,#0
T0E:
RETI
END