CSM-182 - Manchester Computer Architectures, 1948 - 1975

Because of changes in computer technology and terminology, it is often difficult for present-day observers to judge the significance of early digital computer projects. In this paper we follow some architectural themes of interest, as they evolved in the design of three innovative Manchester University computers: the Mark I, Atlas and MU5. Themes such as operand address-generation, instruction formats and memory-management are traced during the period 1948-75. These themes are illustrated by a set of normalised diagrams which may act as an aid to further study of original references.