An apparatus and method for adding input voltage signals. A joining member has displaced connecting ends sized to fit both a standard trailer hitch and a mounting bracket on the step. In a ROM bank read operation, the pre-discharge circuits and pre-charge circuits are activated and deactivated in accordance with the address of the targeted ROM bank. The content server automatically examines the XML input file and converts the definition file to an object type graph and then into a set of SQL instructions as well as a set of web methods. In one aspect, a digital video recorder is connectable to a set-top box configured to receive electronic program guide information and broadcast audiovisual data. The lift also includes a safety lock assembly that automatically engages during upward movement of the lift to prevent unintentional lowering or falling of the lifting carriage.