The RA60, RA80 and RA81

This document provides a detailed overview of Digital Equipment Corporation's Digital Storage Architecture (DSA). It covers the design philosophy behind the architecture, which aims to decouple software, controller, and disk technologies for easier and non-disruptive future advancements. The document highlights the key features of the initial DSA product family members: the UDA50 disk controller, the RA60 removable media disk, and the RA80 and RA81 fixed-media Winchester disks. It provides technical specifications, performance comparisons, and details on data integrity and availability features such as ECC, disk mapping, and radial interconnects.