Data storage apparatus having a columnar array of input-output storage

Abstract

Data storage apparatus having an array of cartridge-storing receptacles with a media device at one extremity of the array, provides cartridge input-output either at all of the receptacles or at a predetermined number of such receptacles. The media device may face the travel of an accessing mechanism such that a holder in accessing mechanism loads a cartridge onto the media device while the holder is situated at the media device. Interlock means prevent the removal of cartridges while the accessing means holder is active in an IO range of the receptacles. Moving the accessing means out of the IO range of receptacles, such as to the media device, enables manual insertion and removal of cartridges. A plurality of the cartridges are kept in respective slots of the cassettes. These cassettes are removably inserted into respective ones of the receptacles. Insertion and removal of cartridges is via manually removing a cassette from its receptacle, changing any cartridges, then returning the cassette, or a replacement, into its receptacle. Each slot of each receptacle in the IO range provides for cartridge input-output as well as long-term storage of cartridges therein. Manual requests for changing cartridges are honored during data processing. In response to a request, the holder is move out of the IO range and kept outside of the IO range. The cartridges are exchanged. Then a manual indication is given that the cartridge changing is complete. An automatic inventory of the removed cassettes ensues followed by usual data processing.