[Gdeaver]

There are absolute rotary position sensors that are sensing over the full 360 range with no mechanical or electrical limits. Vishay 981HE is one model. They are analog voltage from .5 to 4.5 volts so they do not give 10 bit AD resolution. About .5 degrees is the best you can get. Note this is a NI module limitation. Not the limitation of the sensors. There are SSI output sensors that can give 12 bit resolution thru a SPI like interface. We use them to control the steering angle of our pivot module and last year they feed the PID for our arm.