how to put 1/module in formula for making a spur gear

I want to create the formula
DiametricalPitch=1/module=0.5
but as i enter the value i get 500000mm instead of 0.5...
my units are set in mm but still i think the default unit for 1, its taking metre.. plz help me out
i have attached the image of input as well as error

Accepted answer

change your Tools Options to show branches in the spec tree of all your parameters and formulas


1 Other answer

add units to the formula like this:
DiametricalPitch=1mm/module