Basil architecture - an hll minicomputer

Abstract

During the past several years a computer-aided design system (the Logic Machine) has been under development in our laboratory. Briefly, the Logic Machine consists of a microprogrammable control processor, one or more functional units, one or more bidirectional buses, and a microprogram all arranged to perform a specific digital algorithm. Our major goal has been to be able to construct any digital device with this system. We have been able to build a graphics display terminal (1), a floating point processor (2), string/array auxiliary processor (3), and a minicomputer (4). It has amazed us to see how simple and fruitful it has been to construct these devices. In this paper we describe the use of the Logic Machine design system to build still another digital device, a high-level language minicomputer. The motivation for this effort is probably obvious to all hardware designers; software is the most expensive part of a computer system and a high-level language computer will significantly reduce software costs. Not so obvious is the task simplification at the systems programming level, enabling a programmer to quickly review his work, decide on additions or corrections, and expand a program or system. These benefits reduce the layers of logic and, we are convinced, will enable much more sophisticated software systems to be built.