HAI,
MADE 2 MISTAKES DAIRE,

1)U SHOULD KICK ON UR SENSORS.THAT PART I MISSED IN THE PROGRAM
2)Plz replace the ISS with the following code!
.ORG 1000H
CLR TR0
CLR TF0
CPL P1.0 ; TOGGLEING TO GET SQUARE WAVE
mov a,count1
add a,#01h
mov count1,a
JNC OUT1
CLR C
INC COUNT2 ;16 BIT COUNTING IS USED U SHALL MODIFY AS U REQUIRE
OUT1:
MOV TH0,#00H ;VALUE1
MOV TL0,#00H ;VALUE2
SETB TR0
RETI