Let's Make Robots!

Setting up an interrupt properly

For school this year we are making picaxe 08m robots and have a sheet of funtions we need to fill out. This one is attempting to seek shade It needs more work but right now i just need help with the interrupt code,  I have this code here

symbol light = pin3
symbol movment = w0
setint %00100000,%00100000

top:
if light = 0 then low 1
if light = 0 then gosub find
endif
if light = 1 then high 1 low 2 low 4
endif
goto top