Light changeing script

i been working on warp core model for fun of it but i need script that well change light glow in some of glass so go's on and off why go's up and down if know what i mean

here image of core http://img93.imageshack.us/img93/4905/warpcore1001.png

i not added light part to it yet cos am not sure how go by makeing come on and off yet

default
{
state_entry()
{
llSetPrimitiveParams([PRIM_GLOW, ALL_SIDES, .0]);
llSetPrimitiveParams([PRIM_FULLBRIGHT, ALL_SIDES, FALSE]);
}
touch_start(integer total_number)
{
state two;
}
}
state two
{
state_entry()
{
llSetPrimitiveParams([PRIM_GLOW, ALL_SIDES, .2]);
llSetPrimitiveParams([PRIM_FULLBRIGHT, ALL_SIDES, TRUE]);
}
touch_start(integer total_number)
{
state default;
}
}