Design Innovations of the IBM 3830 and 2835 Storage Control Units

The IBM 2305 Fixed Head Storage and IBM 3330 Disk Storage provide significant performance improvements over previously available disk facilities. Many of the improvements were made possible by the design of the control units, which are complex systems that integrate analog and digital interfaces. Definition of control unit requirements and characteristics permitted a large degree of commonality to be achieved between the two control units. The available design alternatives and implementations are discussed.