Abstract: A read only input system provides a source of information for a controller of an automated data storage library, separate from the controller stored microcode, and that will be available for use by the controller after the controller microcode has been updated or restored. The read only input system comprises a bar code reader mounted on an accessor of the library and coupled to the controller for providing the output of the bar code reader to the controller, and a bar code label mounted in the automated data storage library, positioned at a predetermined fixed location. The bar code label encodes input control information for the controller, which is read by the bar code reader and supplied to the controller. The bar code label input control information may comprise an offset value for at least one of the X, Y and Z direction coordinates of the accessor in order to align the accessor.