So where do rotary joysticks hook up?

[Brad Lee]

Using Ipac and/or optiPac, what goes to where?
Can it be done with just an Ipac, to implement dual sticks with both of them rotate-able?

[JustMichael]

What type of rotary joystick?  There are optical rotary ones and the click type rotaries (like in Ikari Warriors).  The optical ones can be hooked up to the opti-pac and the click type ones can be hooked up to Druin's interface.