Resources are provided on the CFA to aid optics development. Power (5, 15, and 72 VDC) and a 48-bit external digital bus are provided on the CFA to operate the positioners, light sources, and detectors that comprise optical systems. A variety of specialized cards (described below) are being produced as part of the Open AUC Project to help interface optical systems to the signal bus. Since 48-bit digital I/O cards are widely available, developers can choose computers and operating systems that fit their requirements. There also is an internal data bus that provides the signals needed to synchronize external electronics to the spinning rotor (described below). Motion control may be provided by servos or by stepping motors. Descriptions, schematics, and timing diagrams for the bus signals will be published, as will the data bus and motion control driver software source code. While these resources are provided to help AUC developers, they are not constrained to use them.