An automatic drive unit for a door assembly of the type having a frame with an opening, a door positionable within the opening between an open position and a closed position, and a door actuator for moving the door between the open and closed positions, includes a controller circuit having a power source, a timing circuit for reporting the date and time to a processor, a non-volatile memory, a programmed set of instructions, and a display. The programmed set of instructions are adapted for receiving input of a location and open and close offset times, and storing such information in the memory. The controller circuit executing the instructions determines based on its location and the date a sunrise time and a sunset time, opens the door at the sunrise time plus the open offset time, and closes the door at the sunset time plus the close offset time.
